Nucleic Acid Biosensors: Recent Advances and Perspectives

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Nucleic Acid Biosensors: Recent Advances and Perspectives Yan Du, and Shaojun Dong Anal. Chem., Just Accepted Manuscript • DOI: 10.1021/acs.analchem.6b04190 • Publication Date (Web): 14 Nov 2016 Downloaded from http://pubs.acs.org on November 14, 2016

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Analytical Chemistry

Nucleic Acid Biosensors: Recent Advances and Perspectives

Yan Du, Shaojun Dong*

State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, Jilin, China; E-mail: [email protected]

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INTRODUCTION The creation of biosensors has given rise to a revolution in many fields like medical and health, food inspection, environmental monitor and so on. The simplicity, convenience and accuracy in detection have drawn increasing attention of researchers, which leads to fast development of biosensors.1 The study of nucleic acid based biosensors (NA sensors) has inspired increasing researchers’ attention due to variability and specificity of sequence. Biosensors built with nucleic acid (NA) are usually composed of single-strand (ss) DNA which can hybridize with the complementary strand, possessing exceedingly high efficiency and good specificity, thus the detection of the complementary strand DNA or RNA can be easily realized.2-4 Broadly speaking, the utilization of NA sensors puts the detection of other analytes into reality through functional nucleic acids (FNAs) like aptamer or DNAzyme as their probe molecule, many of which are beyond the intrinsic role as NAs.4,5 In this review, progress in research of biosensors based on DNA and aptamer/DNAzyme throughout recent years (2014-2016) is summarized. The representative properties are listed in this review, together with existing deficiencies and current challenges are also discussed for future development of biosensor technology.

DNA BASED BIOSENSORS DNA based biosensors, also named as DNA sensors or genosensors, are adoptable in inspecting individual genomic or genetic details of a patient or NA sequences for pathogens invasion.4,6 DNA sensors have enormous potential in making sequence-specific information accessible, which is of great significance in many fields especially in clinical, environmental and food analysis.7,8 The detection mainly relies on hybridization with specificity. The well-known specific hybridization property between NA strands is the main principle of DNA sensors detection. Because of such simplicity, DNA hybridization technique is even more frequently used in diagnostic laboratory than direct sequencing method. The methods used for sequences amplification (i.e., polymerase chain reaction (PCR) and other amplification methods), the efficiency of sequences hybridization and the level of background signal comprehensively decide the measurement sensitivity. Various factors like ionic strength, reaction temperature, and some other DNA computation circuit contribute to attunement of specificity.9 2 ACS Paragon Plus Environment

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Genomic sequences analysis has provided a sensitive technological foundation for quantitatively detect infectious disease pathogens and genetic variations (Table 1). In addition, with the same principle used in environmental and food areas, the recognition of genetically modified organism (GMO) or pathogenic bacteria can be visualized. Besides, microRNAs have been hotspot in research of biosensors since they regulate critical gene expression and hold great potential for point-of-care (POC) diagnostics.

APTAMER BASED BIOSENSORS (APTASENSORS) By means of combining in vitro selection or systematic evolution of ligands by exponential enrichment (SELEX), evolution of NAs in test tubes to bind to a wide range of analytes besides DNA or RNA becomes feasible, with high affinity and specificity.10 These binding NAs are known as aptamers. The terminology “aptamer” derives from “aptus” in Latin which means “to fit”, aiming to portray the relationship between aptamers and their binding targets as “lock-and-key”.11 Aptamers turned to be attractive for researchers when they for the first time acted as new recognition elements in biosensors (i.e. aptasensors) around the year of 2004.12-15 Many advantages of aptasensors were shown including high affinity, simple preparation and capacity to form Watson-Crick base pair, thus their targets involved in inorganic ions (K+, Hg2+, etc.), organic molecules (adenosine triphosphate (ATP), cocaine, etc.), large biomolecules (peptides and proteins) and even whole organisms (bacteria and cells), being compatible with various sensing strategies, almost all kinds of detection requirements and readout techniques.5,16,17 What has occurred in the development of aptamers is the expansion of sensing strategies from a few model targets (i.e., thrombin, ATP, and cocaine) to the targets with more significance (i.e., toxins, drugs, antibiotics, insecticides, tumor markers, biomarkers, cells, pathogenic bacterias) which are selectively listed in Table 2. These targets are not limited to certain range and have been broadened to wide varieties in many fields such as clinical diagnostics, environmental and food safety.

DNAZYME BASED BIOSENSORS



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It is known that aptamer selection for metal ions has been a challenge because of the short of good methods for immobilization of metal ions.16 DNAzymes generated by in vitro selection process were found to have the merits of ease in synthesis and functionalization, excellent specificity toward metal ions.18-21 DNAzymes as a class of catalytic NAs, can cleave specific substrates when cofactors, such as metal ions (UO22+, Pb2+, Ni2+, Cu2+, Zn2+) and amion acids (L-histidine), co-exist. A substrate strand and an enzyme strand compose DNAzymes, of which the former contains a single RNA linkage (rA) that serves as a cleavage site while the latter consists of one catalytic core and two arms. When the cofactor is present, the enzyme strand separates the substrate strand into two parts, which makes it possible to design different kinds of cofactor responsive biosensors. For another kind of DNAzyme named G-quadruplex DNAzyme, transformation from G-rich sequence or sequences into a parallel or an antiparallel G-quadruplex will take place in presence of some metal ions such as K+, Pb2+, and NH4+. The G-quadruplex DNAzyme possesses peroxidase-like activity by employing hemin and is usually utilized as a recognition element in biosensors, or as a special label for a broader scope of targets under rational designing.22 NA sensors have good selectivity due to high affinity and structure tunability of NA, while the sensitivity is greatly influenced by signal transducer and amplifier. Numerous signal transduction methods are currently being used for DNA sensors, aptasensors and DNAzyme sensors: fluorescence, electrochemistry, electrochemiluminescence (ECL), chemiluminescence (CL), colorimetry, surface plasmon resonance (SPR) etc.. In order to achieve higher sensitivity, various of amplification techniques have also been introduced in NA sensors mainly including amplification of the target molecule and amplification of the detection signal. In this review we will summarize some representative biosensors reported in recent years (2014-2016) constructed with different signal transduction approaches and possible collateral amplification techniques. Moreover, the biosensors have been tested through analysis of diluted biological fluids, foods, or environmental samples with satisfactory recovery of the targets. Hence, the most significant concern is not only the achievement of excellent biosensors performance but also their development towards the realization of application in real samples determination.


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METHODS AND IMPROVEMENTS FLUORESCENT DETECTION Fluorescence, as a pioneering tool has wide applications in the whole bio-/biochemical research. Therefore, it is deserved to be incorporated into the design of NA sensors where target-triggered conformation change of oligonucleotides (oligos) influences the fluorescence of traditional DNA binding dyes such as TOTO, or OliGreen, ethidium bromide (EB). However, as the shortcomings of traditional organic dyes like broad emission, narrow absorption, photobleaching and so on, more fluorescent materials have been extensively investigated in the recent decades, including quantum dots (QDs),23 upconversion nanoparticles (UCNPs)24 and nanoclusters (NCs).25 These alternative materials represent many competitive advantages such as outstanding spectral and light physical properties. For example, a fluorescence resonance energy transfer (FRET) system based on donor (CdS QDs) and acceptor (polypyrrole) was integrated into aptasensor for analyzing adenosine in urine samples of lung cancer patients.26 Statistical results for comparisons of the experimental results between the proposed method and high performance liquid chromatography- ultraviolet (HPLC-UV) for determination of adenosine in human urine samples were also obtained. Another FRET aptasensor for kanamycin detection was developed with UCNPs and graphene as the energy donor and acceptor, respectively.27 The detection could proceed in diluted human serum sample with a limit of detection (LOD) of 18 pM. Zhang et al. proposed a label-free fluorescence aptasensor induced by kissing complexes with DNAtemplated AgNCs (DNA/AgNCs) as a signal transducer.28 Similarly, copper nanoparticles (CuNPs) formation from low concentration of CuSO4 under the ss poly T template led to excellent fluorescence. A simple, rapid, sensitive fluorescent biosensor for protein detection was constructed.29 G-quadruplex DNA based strategies. The G-quadruplex DNA based strategy is usually employed by the enhancement effect for fluorescent properties of some molecules such as Ru[(bpy)2(bqdppz)]2+,30 N-methyl mesoporphyrin IX (NMM),31-33 zinc phthalocyanine (Zn-DIGP),34 protoporphyrin IX (PPIX)35,36 and zinc protoporphyrin IX (ZnPPIX)37 through the specific binding with G-quadruplex DNA in presence of several kinds of small molecules38 or metals39 as a co-factor. In order to verify the possibility of engaging G-quadruplexe 5 ACS Paragon Plus Environment


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DNA into the label-free fluorescence sensing,22 in recent years, efforts for new G-quadruplex binding probes have been devoted, such as berberine38,40 and thioflavin T (ThT)39,41. For example, Chen et al. proposed novel fluorescent biosensor detecting Tb3+ by conversion of G-quadruplex DNA induced by ThT and Tb3+ ions.39 As shown in Figure 1A, the presence of K+ stabilizes parallel G-quadruplex, which ThT could bind with and elevate fluorescence intensity. The addition of Tb3+ destroyed the parallel G-quadruplex structure and decreased the fluorescence. The LOD was as low as 0.55 pM. Fu et al. developed a DNAzyme sensor for amplified “turn-on” fluorescence detection of Pb2+ with a LOD of 3 nM.37 In presence of Pb2+, the caged G-rich sequence can be released from the hairpin substrate strand by enzymatic cleavage of DNAzyme, and form the G-quadruplex nanostructure. The signal transduction process relies on contrasting fluorescence output of ZnPPIX fluorophore before and after binding with G-quadruplexes. Moreover, release of DNAzyme catalyzes a new round reaction, thus amplifying fluorescence enhancement in spite of the small amount of Pb2+. This biosensor succeeded in detection of Pb2+ in river water samples with high sensitivity and selectivity. Such a system might offer a prevalent DNAzyme-based sensing platform for sensitive detection of diverse targets in environmental and biomedical fields. Wang et al. carried out ultrasensitive detection of folate receptors by a target-triggered isothermally exponential amplification reaction (EXPAR)-based DNAzyme sensor through ZnPPIX/G-quadruplex probes incorporation, with excellent specificity, high sensitivity and a LOD of 0.23 fM.42 Our group demonstrated the role of integrated nanoassemblies composed of G-quadruplex/PPIX as a synergistic platform for targeted high-performance photodynamic therapy (PDT).43 Sensitiser PPIX was loaded on G-quadruplex which endowed the system cancer cell targeting ability. Following nucleolin-mediated efficient binding and cellular uptake of nanoassemblies, the strong red fluorescence of G-quadruplex/PPIX complex assumed the duty of biological imaging. Meanwhile, the reactive oxygen species (ROS) produced by G-quadruplex/PPIX under light illumination could effectively kill cancer cells. The simplicity in composition by DNA and photosensitizers of this approach avoids the usage of any complicated and time-consuming covalent modification or chemical labeling procedures. Recently, as the flexible structure and unique design of recombined G-quadruplex structure, the split Gquadruplex has been regarded as a binary probe in many fields. On the basis of the cofactor-dependent 6 ACS Paragon Plus Environment

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and mismatch-influenced ligation efficiency of DNA ligase, our group fabricated a versatile, noncovalent labeling fluorescent strategy for cofactor (ATP and nicotinamide adenine dinucleotide (NAD+)) detection and single nucleotide polymorphism (SNP) discrimination by combination of DNA ligation and split G-quadruplex probes.33 Also, our group investigated how to split a G-quadruplex for DNA detection with the perspective from the split mode and guanine base number.44 Different split modes on the split G-quadruplex were inspected and the split mode of 4 : 8 was found to have the highest signal to background ratio. The low fluorescence emission of PPIX in existence of eight-guanine-base in G-rich strand achieved the success of the magic “law of 4 : 8” for splitting a G-quadruplex. Taking advantage of the low background in this mode, a super strategy for DNA detection was performed on the point mutations of a Janus kinase 2 V617F mutation (JAK2 V617F) and b-globin (HBB) genes. Triplex DNA based strategies. The first report on triple-helix molecular switch (THMS) based fluorescent aptasensors, was given by Tan Group in 2011.45 In the design (Figure 1B), aptamer was neighboring to two arm fragments and a dual-labeled oligo served as a signal transduction probe (STP) that can complementarily bind with the arm fragment sequence. Binding of two arm segments of the aptamer with the loop sequence of STP facilitates the formation of an “open” configuration. The aptamer/target complex led to release of the STP and new signal readout. This approach has generality for wide range of analyte by only changing the aptamer sequence and the triple-helix structure remains the same. Benefitting from this, detection focused on targets of thrombin,45 ATP,45 L-argininamide,45 K+ ions46 and tetracycline (TET)47 has been established. Considering the familiar molecular beacon-based signaling aptamers and double-helix DNA molecular switches, several remarkable features of the THMS are summarized as follows: No labeling is required for the original aptamer; the constitution of a triple-helix structure with two shortarmed complementary oligos of the aptamer obtains an improved favorableness to enhance the stability with free aptamer sequence left, so maintaining both the binding affinity and specificity of the aptamer, or even harvesting higher sensitivity. What is more favorable for the research is the generality of the strategy in realization of one STP is qualified for multiplex targets detection merely via aptamers selection, signifying accommodation of more targets meanwhile sustaining the simplicity and cheapness of the STP synthesis. 7 ACS Paragon Plus Environment


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Another novel aptasensor was developed for protein detection, combining the amplification property of PCR and sequence-specific recognition ability of triplex formation for DNA duplex.48 Upon the addition of thrombin, two DNA probes hybridized with each other, one of which was extended when Klenow Fragment polymerase and dNTPs were present. With Taq DNA Polymerase and two primers added, the PCR amplification started, followed by product recognition by molecular beacon through triplex formation. The most significant contribution is the complete elimination of non-specific amplification and DNA contamination. Carbon nanomaterials based strategies. Carbon nanomaterials decorated with carboxyl groups, have been broadly applied in NA sensors which is rendered by excellent fluorescence quenching ability and good interaction with ssDNA through π-π stacking. Being adequate for detecting metal ions, proteins, DNA mutations and other compounds, carbon nanomaterials covering graphene oxide (GO),49-52 carbon nanotubes (CNTs),53 nano-graphite54 and oxidized mesoporous carbon nanospheres (OMCN)55 have been engaged in NA based sensors and the brief summary is presented here. Recently, it was demonstrated that double-strand (ds) DNA/GO complex could be formed through binding of dsDNA and GO in presence of certain salts and the interaction between them was systematically investigated. A fluorescent aptasensor was developed with dsDNA/GO as the signal probe meanwhile utilizing the activities of exonuclease (Exo) I.50 A small Kd value of 311.0 mM and a LOD of 3.1 mM for adenosine were obtained compared with that of the method with GO and dye labeled aptamer (Kd: 688.8 mM, LOD: 21.2 mM). In addition, decent results were obtained in specificity test and the detection of adenosine in human serum was realized. As the large surface area, high pore volume of three-dimensional (3D)-spherical structured OMCN, it has been exploited as an excellent drug carrier and photothermal convertor for cancer photothermochemotherapy.56 A dye (Cy3)-labeled aptamer reported by Li et al. could specifically bind with cell-surface mucin1 (MUC1) marker overexpressed in many malignant tumors including breast cancer and prostate cancer, and stacked on OMCN surface through π-π interactions for the “turn-on” fluorescent aptasensor (Figure 1C).55 Featured by OMCN, the fluorescent aptasensor could both sensitively quantify the MUC1 molecules and Michigan cancer foundation-7 (MCF-7) breast cancer


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cells in fluid, and specifically image the cancer cells, ex vivo tissues, and solid tumors. Thereby, the prepared aptasensor could realize multiple diagnosis of cancer in vitro and in vivo. DNA-based molecular logic computation has attracted extensive attention in the field of bioanalysis, intelligent diagnostics of diseases and other nanotechnology areas. Herein, using 2-to-1 and 4-to-2 encoders and a 1-to-2 decoder as model molecular logic devices, our group for the first time has combined the quenching ability of GO to DNA/AgNCs with enhanced fluorescence intensity of porphyrin dyes by G-quadruplex for preparation of label-free and enzyme-free dual-output advanced DNA molecular logic devices.57 Besides, a comparator was also operated. The illustrated platform possesses several advantages like time-saving, cost-efficient and high generality for the fabrication of other dual output advanced logic devices. Metal-enhanced fluorescence (MEF) based strategies. The MEF effect is dependent on SPR of noble metal NPs. By placing a fluorophore near metal NPs, MEF occurs when the fluorophore is excited, during which the exciton can interact strongly with the localized surface plasmon. Metal NPs can either enhance or quench the emission of the fluorophore, with a delicate dependence on the distance between the metal surface and the molecular orientation. Metal NPs usage for enhanced fluorescence possesses additional advantages, including increased photostability, and reduced blinking. The greatly improved detection sensitivity using surface plasmon field-enhanced fluorescence is considered to be promising for a range of applications with biosensor technology included. For example, a AgNPs-enhanced time-resolved fluorescence (TR-FL) sensor based on Mn-doped ZnS QDs with durable fluorescence was developed for the sensitive detection of vascular endothelial growth factor-165 (VEGF165), a predominant cancer biomarker in cancer angiogenesis.58 Compared with the bare TR-FL sensor, the AgNPs-based TR-FL sensor was remarkably improved in fluorescence owing to MEF effect together with the sensitivity increased 11-fold and a LOD of 0.08 nM. The MEF sensing platforms were individually fabricated with the aptamer for Hg2+ ions59 and the aptamer for recombinant hemagglutinin (rHA) protein of H5N1 influenza virus (Figure 1D).60 They both used thiazole orange (TO) as the fluorescent reporter and the aptamers were both immobilized on 9 ACS Paragon Plus Environment


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the surface of the Ag@SiO2NPs which were pre-synthesized. When targets were absent, the aptamers and the dissociative TO in solution showed no fluorescence emission under laser excitation. However, after targets addition, the aptamer folded into secondary structure. In the meantime, TO could interject into the hairpin complex and was gripped by the NA bases with high fluorescence quantum yield under laser excitation. Meanwhile, given the phenomenon that the fluorescence of excited TO was further magnified by MEF effect of Ag@SiO2NPs, the signal was largely increased. The LOD was 0.33 nM for Hg2+ and 2 ng/mL for rHA protein, respectively. The sensing system was also able to detect Hg2+ or rHA protein in complex matrixes (environmental samples or serum, respectively). Only one kind of aptamer strand is desirable and quick detection process in one tube within 30 min makes it suitable as a self-contained diagnostic kit for POC diagnostics. Another notable merit of this sensor is the extremely low background noise induced by signal. Ratiometric fluorescence strategies. Ratiometric fluorescent biosensors with function of self-calibration for amendment of analyteindependent factors, have attracted particular attention in the recent decades. Induced by analyte, the fluorescence intensity at different wavelengths is changed. Similarly as the internal reference approach in other analytical methods, ratiometric fluorescence sensing is equipped with increased signal-to-noise ratio and much more reliable quantification thus has augmented sensitivity and accuracy. A dualemission ratiometric fluorescent aptasensor was designed for detection of ochratoxin A (OTA) via a dual mode of fluorescent sensing and in-situ visual screening realized by FRET.61 Amino-functionalized aptamers were firstly labeled with the green-emitting CdTe QDs (gQDs) donor. The red-emitting CdTe QDs (rQDs) wrapped in the silica sphere functioned as the reference signal. The LOD for OTA was calculated to be 1.67 pg/mL. Many examples for application of signal amplification strategies in FRETbased ratiometric technique have been reported such as hybridization chain reaction (HCR) for detecting Cu2+ ions62 and catalytic hairpin assembly (CHA) for detecting Hg2+ ions.63 The fluorescent intensities ratio of the acceptor to donor was adopted to carry out quantitative detection of Cu2+ with a LOD of 0.5 nM and Hg2+ with a LOD of 7.03 nM, respectively. Our group implemented ratiometric target DNA detection and length measurement by employment of a cascade logic device (Figure 1E).64 Two fluorescence sensitive substrates (i.e. Scopoletin, Sc; Amplex 10 ACS Paragon Plus Environment

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Red, AR) of G-quadruplex/hemin DNAzyme with inverse responses were simultaneously used in one homogeneous system to construct this cascade advanced DNA logic device. As be known that the transformation from non-fluorescent AR to fluorescent resorufin proceeds under oxidation effect of H2O2 catalyzed by DNAzyme, and the oxidative product has fluorescence emission at 585 nm. In contrast, fluorescent Sc has the emission at 465 nm and is oxidized by H2O2 to a non-fluorescent product with unidentified structure under the catalytic effect of DNAzyme. The two substrates of DNAzyme with inverse responses were simultaneously used in one homogeneous system. For the cascade logic programmed target DNA detection, the fluorescence intensity of AR at 585 nm increased regularly meanwhile that of Sc at 465 nm progressively decreased as the concentrations of target varied. The fluorescence intensity ratio (F465/F585) as a function of the logarithmic value of different DNA concentrations was presented and the LOD of 200 pM was obtained by direct measurement. Separation based strategies. Sometimes separation technology is incorporated into fluorescent strategies with nanomaterials like magnetic beads,65 gold nanoparticles (AuNPs),66 and silica nanoparticles (SiNPs)67 used as the separation elements. The detection process relies on the fluorescence change nanomaterials that are separated from the system after target binding. The separation process makes aptamer-target binding independent from homogeneous equilibrium, endowing the sensor with higher sensitivity despite more complexity than the classic homogenous strategy. For example, a novel fluorescence aptasensor responsive to chloramphenicol (CAP) was successfully developed based on magnetic aptamer-liposome vesicle

probe

(Figure

1F).68

Both

the

DIL

(1,1′-dioctadecyl-3,3,3′,3′-

tetramethylindocarbocyanineperchlorate, a lipophilic fluorescent dye to membrane) and ssDNA binding protein (SSB) were immobilized on liposomes for preparation of highly sensitive fluorescence vesicle signal tracer (SSB/DIL-Lip). Upon the vesicle probe solution reacted with CAP, the aptamer immobilized on the magnetic beads preferably bound with CAP, releasing SSB/DIL-Lip vesicle signal tracer in the supernatant. The emission intensity of the released tracer was corresponding to analyte concentration. Upon optimization, a LOD of 1 pM was exhibited and the analysis of CAP in fish sample showed the results which were consistent with the ones obtained by enzyme-linked immunosorbent assay (ELISA) kit. Therefore the methodology had strong ability against interference and was 11 ACS Paragon Plus Environment


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considered to be a promising approach for monitoring CAP quantitatively. Another separation technology based fluorescence aptasensor was reported for facile and sensitive detection of MCF-7 cells.69 Excellent sensitivity with LOD of 70 cells/mL was displayed. In comparison with traditional organic dyes and the newly emerging nano-technological probes, the combination of Tb3+ and ssDNA signal probe can be regarded as a more powerful bio-probe because of its stability in optical property, good biocompatibility and free from ease in synthesis. Other strategies. Although fluorescent aptasensors are progressively regarded as a useful tool for detection of target biomolecules with high reliability, the scarcity of an imaging-based quantitative measurement platform limits their usage with biological samples. A combination of

fluorescent nano-aptasensor and

quantitative fluorescence microscopy (QFM) was performed for quantitative determination of ATP.70 As the core component of aptasensor, SYBR Green-I-intercalated aptamer complexes were covalently immobilized on graphene, enabling quantitative detection of ATP. Also, a number of targets could be covered for the platform including ions, small biomolecules, proteins, and even cells. Another fluorescent and visual aptasensor was developed by Liang et al. for multiplexed monitoring of cancer cells in microfluidic paper-based analytical devices (Figure 1G).71 The aptamers modified QDs were decorated on mesoporous SiNPs. After being absorbed by GO, the fluorescence of QDs was quenched via FRET, but recovered upon the addition of target cells. The unique design allowed for alteration of other target cancer cells merely depending on the change of the aptamer and different colored QDs. What is highly regarded is the realization of simultaneous determination of three different cancer cells. The color changes under a single excitation light could be clearly monitored with naked eye. The resultant LODs were 62, 70 and 65 cells/mL for MCF-7, HL-60, and K562 cells, respectively. Besides, the work contributed to clinical sample analysis with satisfactory results. Enhanced plasmon-mediated fluorescence is observable when a fluorescent molecule is put near the center of metallic structures. It was found that a hot-spot structure triggered surface plasmon coupled emission (SPCE).72 In their design, an ultrathin linking layer composed of cationic polymers and aptamers was fabricated to mediate the assembly of a AgNPs-dyes-gold film with a strongly coupled 12 ACS Paragon Plus Environment

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architecture through sensing a target protein. In absence of targets, the plasmonic assembly was prevented. The presence of targets activated ultrathin layer to link NPs-film junctions. The small gap (no larger than 2 nm) of junction and the large diameter (∼100 nm) of NPs ensure that ultra-strong coupling is achieved to generate intense SPCE. A signal enhancement of more than 500-fold was observed in sensing process. The application of plasmonic nanostructures also provides a simple, reliable, and effective way to facilitate new construction of biosensing.

ELECTROCHEMICAL DETECTION Researchers’ attention has been unceasingly attracted by electrochemical detection method in biosensors since its advantages were recognized: highly sensitive, fast responsive, robust, low-cost, simple-to-operate, easily miniaturized, and easy realization of molecular diagnosis. Therefore, the recent past two years still appeared to be filled with fervor for publication on electrochemical detection method, some of which will be enumerated in this review for their guiding significance in this field. Electrochemical impedance spectroscopy (EIS) strategies. EIS is a label-free detection approach used to measure interfacial molecular interactions and to quantify the target molecules. The sensing relies on the interfacial electron transfer kinetics between the redox probe and the electrode, the embodiment of which is the electrochemical impedance signal remarkably affected by molecular weight and/or high charge density of the target. They have burnt an impression as an effective tool for sensitive detection throughout the long development history. Even in the past two years, new design and improvements have been unceasingly proposed with targets categories largely broadened (such as versicolorin A (VerA),73 brevetoxins (BTXs)74, cylindrospermopsin (CYN)75) and to be more meaningful by assistance from aptamer SELEX. (such as acetamiprid,76 anatoxin-a (ATX),77 progesterone (P4),78 interleukin-17 receptor A (IL-17RA),79 and HepG2 cancer cells 80) Wang et al. reported an EIS-based aptasensor for detecting adenosine by using dual backfillers (dithiothreitol (DTT) and 6-mercaptohexanol (MCH)) with ultra-high sensitivity (Figure 2A).81 The interfacial electron transfer resistance increased with adenosine concentration, and the optimized LOD 13 ACS Paragon Plus Environment


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was 0.02 pM. The coupling configuration of backfillers cyclic-(DTT) and linear-(MCH) could adequately weaken the nonspecific adsorption and the LOD to picomolar level. While in the condition where either of MCH or DTT worked as the backfiller, the LOD was raised (0.03 nM and 0.2 pM for Au/aptamer/MCH and Au/aptamer-DTT, respectively). The reason was attributed to incomplete surface block with MCH or DTT, resulting in incomplete backfilling and related surface defects which lowered the sensitivity. Such a contrast reflected the synergy effect of MCH and DTT in reducing pinhole defects on the electrode surface. Sheng et al. fabricated an EIS cocaine biosensor built with 3D-DNA structure transformed from Triangular Pyramid Frustum DNA to Equilateral Triangle DNA.82 Detection process relied on obvious faradaic impedance change when the aptamer-composed DNA nanostructure switched from close to open triggered by cocaine. The LOD was calculated to be 0.21 nM. The efforts to improve EIS sensors are not only confined to method improvements, but also include technique modifications for further sensitivity increase. An impedimetric aptasensor was developed for nuclear factor kappa B (NF-κB) detection with peroxidase-like mimic coupled DNA nanoladders as signal enhancer.83 The presence of target prompted aptamer to be dissociated from electrode surface and allowed in-situ formation of DNA nanoladders on electrode surface. The peroxidase-like mimic manganese (III) meso-tetrakis (4-Nmethylpyridyl)-porphyrin (MnTMPyP) interacts with DNA nanoladders, and the insoluble benzo-4-chlorohexadienone (4-CD) precipitation derived from the oxidation of 4-chloro-1-naphthol (4-CN) could be formed on electrode surface in presence of H2O2, resulting in a significantly amplified EIS signal output for quantitative target analysis. As a result, the developed aptasensor showed a LOD of 7 pM. It is also important to evaluate the performance of the biosensors in real complex matrix. However, EIS method is susceptible to nonspecific binding of contaminant on electrode surface, resulting in nonspecific impedance changes which can be evaded accordingly by adopting rigorous control and optimization.84 For examples, a novel nano-structured platform based on IrO2NPs was designed by Merkoci Group to improve the performance in impedimetric biosensors.85 It was claimed that low matrix effects were produced during their detection of OTA in white wine samples, illustrating the availability of the sensing system in analyzing real samples. An EIS sensor was built with AuNPs modified pencil graphite electrode for detection of Bacillus cereus.86 The as-prepared biosensor had high accuracy in the recognizing nonhaemolytic enterotoxin (nhe) A (nheA gene) which was the most 14 ACS Paragon Plus Environment

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prevalent in all subspecies of Bacillus cereus, in real samples like milk and infant formula. Tabrizi et al. successfully synthesized ordered mesoporous carbon-gold nanocomposites that were modified on screen printed electrode to construct an EIS aptasensor applied to the determination of VEGF165 in serum sample of a lung cancer patient.87 The recovery of the analysis was about 97.1%, calculated by the tested concentration of VEGF165 in serum of lung cancer patient (712.2 pg/mL) and a standard ELISA value in local hospital (733.5 pg/mL). These publications represent huge potential for various diagnostic applications. Photoelectrochemistry (PEC) strategies. PEC sensing strategy was derived by grafting the same principle of solar energy device to NA sensors and has attracted great attention due to the simplicity in operation, quickness of response, less interference from low background signal and excellence in sensitivity. These advantages are traced to the combination of superiority in electrochemical technique and compatibility due to the different forms of energy for excitation (light) and detection (current). So far, examples on PEC strategies applied in the field of NA sensors have been increasingly common. Research achievements cover wide range of targets such as DNA,88 thrombin,89 Hg2+ ions,90 17β-estradiol (E2)91 and acetamiprid92 etc. A thrombin aptasensor based on PEC strategy was constructed by using graphene-CdS nanocomposites multilayer as photoactive species and electroactive mediator hexaammineruthenium(III) chloride (Ru(NH3)63+) to enhance signal.93 The aptasensor possesses good sensitivity for thrombin detection with the LOD of 1.0 pM. Zhang Group employed a graphene doping p-type semiconductor BiOI as photoactive species to construct PEC aptasensor for detection of oxytetracycline (OTC).94 BiOI was used here for generating a cathodic photocurrent signal. In presence of OTC, a decrease of photocurrent was recorded owing to the specific capture of OTC by aptamer. The LOD was estimated to be 0.9 nM. PEC aptasensors performance has been even tested in real sample detection. Du et al. investigated the performance of their PEC aptasensor in monitoring microcystin-LR (MC-LR) residues in fish samples bought from the local supermarket.95 The total analytical recovery of MC-LR was from 97.8% to 101.6%, with relative standard deviation (RSD) of 2.52% to 5.14%, illustrating the great potential in real sample analysis. Another PEC aptasensor for E2 detection in environmental water samples was demonstrated, exempt from complicated sample pretreatments, and the analytical results almost 15 ACS Paragon Plus Environment


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equivalent to that determined by HPLC were obtained.91 The work contributed to application of PEC aptasensor in monitoring environmental water pollution. In spite of the satisfactory achievements in PEC strategy, it is still in its infancy and needs further evolution. An accomplished triumph in improving detection with augmented accuracy and sensitivity is realized by signal amplification strategy.96 For example, according to Tang Group’s report, HCR as amplification method was assembled in establishment of Ir(III) complex-based PEC DNA sensor with a cationic Ir(III) complex serving as a DNA intercalated indicator. As shown in Figure 2B, the ITO electrode functionalized by AuNPs on which thiol-DNA was assembled as the sensing interface. When target DNA is absent, both H1 and H2 hairpins are in closed state, at the same time almost no interaction occurs between Ir(III) complex and short ssDNA, causing low background signal. When target DNA exists, one end is captured by ssDNA on electrode simultaneously the other end triggers HCR with the assistance of hairpins H1 and H2. Long dsDNAs can form as long as target DNA is present, despite the LOD at femtomolar level. The high sensitivity benefits from the amplification effect of HCR and excellent PEC performance of the Ir(III) complex. Mimetic enzyme-amplified strategies. As another powerful technology, electrocatalysis also plays vital roles in constructions of NA sensor field. The introduction of natural enzymes in electrocatalytic biosensors makes the detection more sensitive and selective. However, some recognized disadvantages of the natural enzymes like high cost and complicated purification process, time-consuming, and easy loss of catalytic activity in environmental conditions. Besides the natural enzymes,97 substantial efforts have been devoted in research of mimetic enzyme-amplified strategies in recent years with advanced merits including simple structure, stable chemical properties, easy synthesis and high catalytic efficiency. The mimetic enzymes with wide applications for fabrication of amplified NA sensors, including manganese porphyrin (MnTPP),98 graphene99 or nano-/bio-material-graphene hybrids,100 DNA/AgNCs,101 hemin related DNAzyme,102 were studied in recent years. For examples, a first report with graphene as the nanocatalyst in an amplified aptasensor was demonstrated where the electrocatalytic property of graphene toward ascorbic acid (AA) oxidation was 16 ACS Paragon Plus Environment

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used.99 In their design, the acquired graphene/thiol-aptamer/Au electrode produced a remarkable electrocatalytic signal for AA oxidation. Li et al. fabricated a sensitive DNA sensor with GO-thionineAu@SiO2 nanocomposites modified DNA probe for detection of Escherichia coli O157:H7 gene through a famous horseradish peroxidase (HRP)-mimicking DNAzyme, G-quadruplex /hemin, as a biocatalyst in presence of substrate H2O2.103 A sensitive turn-on aptasensor for detection of lysozyme was dependent on the mimic peroxidase catalytic property of DNA/AgNCs and HCR for signal amplification (Figure 2C).101 The designed DNA duplex composed of capture DNA and aptamer was fixed on the electrode. In presence of lysozyme, the DNA sequence binding with lysozyme was released, giving exposure of the induced DNA sequence, which orderly initiated the formation of the supersandwich DNA structure by HCR amplification. Because of the smart design of cytosine-rich sequence, formation of DNA/AgNCs on supersandwich DNA structure generated peroxidase catalytic property. The sensing strategy showed a satisfactory LOD of 42 pM for lysozyme detection. From the work mentioned above, it is predictable that mimetic enzymes would become promising alternatives of natural enzymes as amplifying-elements in DNA sensors. DNA tetrahedral nanostructure strategies. Fan Group was the first one to employ DNA tetrahedral nanostructure as the probe to construct electrochemical biosensor.104,105 Due to the ease in control of the surface on which the biomolecule is confined, tetrahedral nanostructured probe has been applied in detection of synthetic ssDNA and other samples at molecular level with improved molecular recognition at the biosensing interface. In 2015, tetrahedral DNA probe was first put into use in electrochemical biosensor for detection of hemagglutinin (HA) gene extracted from influenza A (H7N9) virus copied from clinical throat-swab samples (Figure 2D).106 In presence of target sequence, a biotin-labeled (bio)-ssDNA was introduced to form a sandwich structure with the tetrahedral nanostructured probe pre-immobilized onto the Au electrode surface by strong Au-S chemical bonds. Then, through specific binding with the bio-ssDNA, avidin-HRP as signal transducer, was used to monitor the hybridization reaction, with the LOD reaching 100 fM. In selectivity tests, target DNA of influenza A (H7N9) virus could be distinguished from other types of influenza A viruses (H1N1 and H3N2), and even from single-base mismatch oligos. Moreover, the biosensor was able to sensitively detect asymmetric PCR ssDNA products of trace cDNA in 17 ACS Paragon Plus Environment


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influenza A (H7N9) HA gene in spite of only three PCR cycles. The result made people believe the great possibility for DNA tetrahedra to be used to detect H7N9 virus and other pathogens at the gene level. Besides, the tetrahedral DNA nanostructure probes have been combined with different amplification techniques, establishing sensitive detection of microRNAs (microRNA-122b107 and microRNA-21108). The former LOD was 10 aM and the latter one was 0.4 fM. The practical utility of the microRNA was expressed in detection of serum samples from breast cancer patients with decent recovery rate, as well as the accuracy and effectiveness in analysis of other biological fluids were also demonstrated.108 Ratiometric electrochemistry strategies. Ratiometric electrochemical strategy regards the ratio of the signals between two probes as the final

signal output to detect analytes. Ellington Group’s work for the first time employing ratiometric analyses in electrochemical DNA sensors made the sensor more robust and reproducible.109 This design originated from Plaxco’s E-sensor approach110 except for addition of the second redox component as the internal control redox probe (here, ferrocene (Fc)). As shown in Figure 2E, in presence of target DNA, the distance between signal probe (here, methylene blue (MB)) and electrode surface is the only measurable variable, while the distance between control probe and electrode remains relatively constant. The introduction of the internal control overcame the irreproducibility but maintained good sensitivity or selectivity with a LOD of 25.1 pM for human T-lymphotropic virus type I gene fragment. Ratiometric strategy eliminates false positive results brought by external factors in traditional detection strategies where analytes are embodied by single signal, thus is more reliable and stable with good sensitivity and broad detection range. As a new hotspot in recent research of novel sensors, ratiometric strategy is promising to constitute a series of electrochemical DNA sensors111 or aptasensors.112-116 As one typical example, dual-signaling electrochemical aptasensor based on sandwich structure was reported.114 The developed ratiometric aptasensor showed good response toward thrombin with a LOD of 170 pM. Other examples include Exo III-assisted target recycling amplification strategy111 and CHA amplification strategy115. Also, Yu et al. modified the dual-signaling ratiometric strategy and developed a triple-signaling electrochemical aptasensor for detection of bisphenol A (BPA) by superimposing the triple signal changes.113 18 ACS Paragon Plus Environment

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Immobilization-free electrochemistry strategies. In order to implement sensing, the recognition element immobilization process is usually required for most of the electrochemical biosensors, which is laborious and time-consuming. Hence, there is a great need for new electrochemical strategies which are immobilization-free and straightforward to use. The first report on immobilization-free electrochemical biosensing strategy appeared in 2012.117 Their electrochemical biosensor worked in homogeneous solution where diffusivity between an oligo and a mononucleotide toward a negatively charged indium tin oxide (ITO) electrode differed, in purpose of direct detection of DNA (Figure 2F). Longer DNA labeled with electroactive probes (e.g. MB or Fc) degraded by enzyme (e.g. nicking enzyme or Exo) in presence of targets. Shorter or less negatively charged DNA inhibited electrostatic repulsion and diffused freely to the negatively charged ITO electrode, promoting enhanced electrochemical signal. However, the signal production of immobilization-free strategy depends on diffusion of electroactive probe from solution to electrode surface, which signifies a lower sensitivity compared to the traditional sensing strategy in which electroactive probes are attached on electrode surface. Therefore, researchers have been attempting to upgrade the detection sensitivity of homogeneous electrochemical biosensors by using efficient signal amplification techniques.118-123 For example, Liu et al. reported an Exo III-aided autocatalytic target recycling strategy as a homogeneous electrochemical sensing platform for DNA and thrombin detection.123 The target DNA fragment produced during recycle process by Exo III served as a target analogue and could trigger the second recycling process. The LODs for target DNA and thrombin were as low as 0.1 and 5 pM, respectively. Besides employment of Exo as amplification recycling elements, Tan et al. also built a nicking endonuclease-assisted target recycling signal amplification method in a homogenous electrochemical DNA sensor to identify target DNA species related to oral cancer overexpressed 1 (ORAOV1) in saliva with the LOD of 0.35 pM.119 The superiority of nicking endonuclease than that of Exo is reflected in the high specificity of the nicking reaction. Another immobilization-free electrochemical biosensor was also reported by the same group for simple and sensitive detection of Pb2+ with a LOD of 18 nM.120 What is worth mentioned is its application in real water samples analysis with satisfactory results.



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ELECTROCHEMILUMINESCENT DETECTION Electrochemiluminescence (electrogenerated chemiluminescence, ECL), a kind of chemiluminescence (CL) driven by electrochemical reaction, is taking the place of traditional electrochemical and CL techniques by its simplification and good controllability. The property of having no-background results in high time and space resolution of the signal and elevated sensitivity. The intrinsic advantages of ECL renders it a powerful tool for highly sensitive and specific detection of various samples thus ECL based biosensor has been another research focus in the field of biological analysis. Simple ECL strategies with improved properties. Simplicity in composition of biosensor is one of the key parameters for practical application and commercialization purpose in biomolecular detection or disease diagnosis, nonetheless excessive simplicity may impair the sensitivity, reproducibility. Researchers have never ceased the steps in pursuit of simple, sensitive and robust ECL sensors.124-127 For example, Li et al. reported a highly sensitive ECL aptasensor to detect proteins by through the introduced auxiliary probe that could enhance the sensitivity.125 A thiolated capture probe was self-assembled on surface of the Au electrode followed by hybridization with the Ru(II) complex labeled probe and the auxiliary probe modification on the electrode. Part of the capture probe bound with analyte thrombin with de-hybridization part consequently hybridizing with the adjacent auxiliary probe, largely shortening the distance between the tagged Ru(II) complex and the electrode surface wherefore the ECL intensity was increased significantly. The attained LOD of thrombin was 2.0 fM. A signal-on ECL DNA sensor based on the dual quenching and strand displacement reaction was designed.126 The terminology “signal-on” originates from target DNA recovers the well-defined ECL signal of QDs already quenched by Fc. The advantages of signal-on detection endow the biosensor with a LOD of 2.4 aM as well as the ability to differentiate single mismatch DNA. Moreover, the ECL DNA sensor visualized target DNA detection in serum sample, showing practical significance in clinical NA analysis. Single-walled carbon nanohorn (SWCNH) has been for the first time discovered to have quenching ability for ECL signal (Figure 3A).127 The assembling of ATP aptamer on the SWCNH/GCE through π-π stacking interactions accommodates more Ru(bpy)32+ molecules adsorbed onto electrode 20 ACS Paragon Plus Environment

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surface via electrostatic interactions between Ru(bpy)32+ and the negatively charged phosphate backbone of DNA. Consequently, SWCNH quenches ECL due to shortened the distance between SWCNH and Ru(bpy)32+ probe. In presence of ATP, its binding with the aptamer impaired the interactions between SWCNH and Ru(bpy)32+, preventing ECL quenching and enhancing the ECL intensity. The method is considered to be time- and cost-effective because the usage of label or amplification is avoided. Signal enhanced strategies by novel ECL reagents. Researchers have been in search of novel ECL reagents, making breakthrough in terms of ECL intensity or ECL properties (e.g., emission wavelength). There have been novel reagents reported which were disclosed to incorporate with signaling materials to amplify the detection signals.128-133 For examples, Yuan Group proposed an aptasensor based on the self-enhanced ECL luminophore of a Ru complex, Ru-Amp (two components of [Ru(phen)2(cpaphen)]2+ and ampicillin) with signal amplified by in situ enzymatic reaction for detection of thrombin with a LOD of 0.33 fM.128 The bilayer structure composed of N-(aminobutyl)-N-(ethylisoluminol)/hemin dual-functionalized graphene hybrids (A-H-GNs) and luminol-functionalized silver/GO composite (luminol-AgNPs-GO) was found to have excellent ECL activity in presence of H2O2, which was utilized to construct a label-free ECL aptasensor for 2,4,6trinitrotoluene (TNT) detection with a LOD of 6.3 × 10−13 g/mL.129 What is worth noting is the feasible detection of TNT in environmental water samples with good recoveries (91.0%-107%) and relative standard deviation (2.1%-6.1%, n = 3). AuNPs capped by 3,4,9,10-perylene tetracarboxylic acid-thiosemicarbazide functionalized C60 nanocomposites (AuNPs/TSC-PTC/C60NPs) as a novel ECL signal tag for detection of thrombin was also reported (Figure 3B).131 In the sensing system, C60NPs were prepared and wrapped with 3,4,9,10perylene tetracarboxylic acid (PTCA) via π-π stacking interactions, followed by linking with TSC via amidation, assembly of AuNPs on the TSC surface by Au-S bonds, and being labeled to the second thrombin aptamer (TBA 2) as the ECL signal amplification tag. Meanwhile, modification of AuNPs/graphene nanocomposites on the surface of a glassy carbon electrode (GCE) was implemented for further immobilization of thiol-terminated thrombin capture aptamer (TBA 1). Owing to the sandwiched reaction, an ECL signal was enhanced appreciably in S2O82−/O2 solution for thrombin with 21 ACS Paragon Plus Environment


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a low LOD of 3.3 fM. Also, in another publication of the same group, the construction of a highly sensitive ECL aptasensor regarding semicarbazide as co-reaction stimulator to accelerate the ECL reaction rate of CdTe QDs and the co-reactant of S2O82− for promotion of signal amplification was demonstrated.132 Here, the co-reaction stimulator interacted with co-reactant instead of luminophore, promoting the rate of ECL reaction between luminophore and co-reactant. The quantitative detection of thrombin had a LOD of 0.03 fM, suggesting the co-reaction accelerator could provide efficient signal amplification. Amplification strategies based on DNA amplification techniques. DNA amplification techniques can be also introduced into ECL sensors to enhance the sensitivity: enzyme-free (such as hybridization-based HCR134), enzyme-based (such as nicking endonuclease signal amplification (NESA)135 and polymerase-assisted rolling circle amplification (RCA)136) amplification techniques etc. By using Exo-catalyzed target recycling and HCR to amplify the signal, Wu et al. proposed an ECL aptasensor for the detection of thrombin.134 The aptamer degraded by exonucleased after dissociation from the dsDNA in presence of thrombin. The released target was recycled for amplification effect, resulting in extended dsDNA under the help of capture probe and two hairpin structures through HCR on the electrode surface. The proposed strategy exhibited a LOD of 0.23 pmol/L by virtue of multiple signal amplification strategy. Another dual amplified ECL biosensor based on Pb2+-induced DNAzyme-assisted target recycling and RCA was successfully fabricated for microRNA (miRNA) detection (Figure 3C).136 A Y-junction formed with the primer probe, assistant probe and miRNA was separated upon the addition of Pb2+ to release miRNA which initiated the following recycling process, producing numerous intermediate DNA sequences (S2). The employment of a DNA sequence (S1) modified by dopamine (DA) aimed to hybridize with a hairpin probe fixed on AuNPs/GCE and utilize the quenching effect of DA to quench luminol ECL signal for acquisition of ultralow background signal. Thereafter, as a production of the target recycling process, S2 displaced S1 and was loaded onto electrode to trigger RCA. Gquadruplex/hemin DNAzyme was generated, exhibiting strong catalytic effect toward reaction between H2O2 and luminol, displaying amplification effect for ECL signal. A LOD of 0.3 fM was reported. In a recent report, a design for detection of p53 DNA sequence, that suppresses tumor cell malignant 22 ACS Paragon Plus Environment

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transformation was proposed by constructing an ultrasensitive and specific ECL biosensor based on cascade signal amplification of NESA and hyperbranched RCA (HRCA).137 NESA possesses unique characteristics for specific recognition, while HRCA derived from RCA can reach higher amplification efficiency (109-fold). The ultimate LOD for p53 DNA sequence detection was 0.02 fM using this cascade amplification strategy. Ratiometric electrochemiluminescent strategies. When the newly emerging ratiometric strategy is combined with ECL, the detection principle is based on the ratio of ECL peak intensity on cathode to anode, and the results are with more accuracy through the self-calibration of two emission bands. For example, a ratiometric ECL biosensor analyzing Mg2+ was reported (Figure 3D).138 The system consists of QDs functionalized by DNAzyme as capture probes and cathode ECL emitters, luminol-reduced AuNPs (Au@luminol) as anode ECL emitters, and a Mg2+ dependent DNAzyme modified with a cyanine dye (Cy5) fluorophore as the quencher. The ECL of the cathode QDs was quenched by electrochemiluminescence resonance energy transfer (ECL-RET) between CdS QDs and Cy5 molecule, meanwhile the ECL from anode Au@luminol was produced. In presence of Mg2+, Cy5 and Au@luminol were released after the DNAzyme cleaved the substrate strand, consequently leading to the recovery of the ECL of the cathode QDs and the decrease of the ECL on anode simultaneously. The LOD was calculated to be 2.8 µM, omitting the process of separation and enrichment. Mg2+ detection in Hela cell extract was realized in this work, where the DNAzyme triggered ratiometric ECL strategy would also promote the application in biosensing and clinical diagnosis. A ratiometric ECL-RET system which was applied for Pb2+ detection was also developed with a LOD of 0.35 pM.139 Usually, ratiometric ECL sensors work by employment of single working electrode with two probes modification that harvest ECL signal at different potentials. Enlightened by the phenomenon that ECL signal is produced from the probes at different potentials, Feng et al. designed a screen-printed carbon electrode array which is composed of two spatial-resolved working electrodes (WE1 and WE2) for detection of CAP by ratiometric ECL strategy.140 The ECL signals from WE1 and WE2 were regarded as the working signal and the internal reference standard signal, both of which were generated at



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different electrodes thus were able to reduce the matrix interference. This platform offers a selective and sensitive route for detection of CAP in food analysis.

CHEMILUMINESCENT DETECTION Chemiluminescence (CL) sensor relies on illumination (chemiluminiscence) produced by chemical reactions for trace analysis, which is exempt from light source and avoids interference from light scattering, thus possessing high sensitivity, simplicity in instruments setup, operation wide calibration ranges and fitness for miniaturization.141 In this review, only strategies reported in the recent years based on G-quadruplex/hemin DNAzyme, guanine (G) nucleobases and Au nanostructures will be presented. G-quadruplex/hemin DNAzyme based strategies. The G-quadruplex/hemin DNAzyme results in peroxidase-like activity by using common substrates in peroxidase activity CL assays, such as luminol catalysis-oxidized by H2O2.142,143 It is known that Gquadruplex/hemin DNAzyme has almost 250-fold peroxidase activity of the free hemin. Thus, it is usually utilized as a recognition element or a special label in numerous biosensors. For examples, cascade autocatalytic recycling amplification strategy assisted by Exo III was proposed in pursuance of label-free CL detection for platelet-derived growth factor BB (PDGF-BB).144 As shown in Figure 4A, the components including a duplex DNA (aptamer-blocker hybrid), two kinds of hairpin structures, and Exo III comprise the whole system. When recognizing PDGF-BB, a close configuration was formed by folding of aptamer which initiated the proposed Exo III-assisted cascade autocatalytic recycling amplification reaction. As a consequence, plenty of released “caged” G-quadruplex sequences intercalated hemin to catalyze the oxidation of luminol by H2O2, yielding amplified CL signal. Excellent specificity and high sensitivity with a LOD of 0.68 pM PDGF-BB were all achieved. The proposed strategy was considered to have superiority like simple design, isothermal conditions, homogeneous reaction free from separation and washing steps, effective-cost with no labeling, and high amplification efficiency. Jo et al. reported a chemiluminescence resonance energy transfer (CRET) aptasensor for the detection of OTA in roasted coffee beans through the quenching effect of Dabcyl at 24 ACS Paragon Plus Environment

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the end of the OTA aptamer region.145 The signal decrease corresponded to increase of the OTA concentration with a LOD of 0.22 ng/mL as well as recovery rate of 71.5% and 93.3% for 1 ng/mL and 10 ng/mL spiked coffee samples, respectively. Guanine nucleobases based strategies. What is already known is that the strong CL signal can be achieved via the derivatization reaction between phenylglyoxal (PGO, a special CL reagent) and guanine nucleobases of DNA. It was found that GO-aptamer complex showed strong CL intensity originating from the instantaneous derivative reaction between PGO and guanine nucleobases of aptamer that were adsorbed on GO surface.146 In absence of target, the GO-aptamer complex formed by π-π stacking were washed and separated by centrifugation for direct CL analysis. In contrast, in presence of target, the weak binding between aptamer-target complexes and GO surface decreased the amount of aptamers adsorbed on GO surface, resulting in significantly decreased CL emission. Similar systems for detection of other molecules including cocaine, thrombin, and IgE can be easily established, showing the generality of the sensing platform in the areas of small molecule detection and protein analysis. Light illumination produced by the reaction of guanine nucleotides and 3,4,5-trimethoxylphenylglyoxal (TMPG, one of PGO analogues) in presence of tetra-n-propylammonium hydroxide (TPA) and N,Ndimethylformamide (DMF) has also been investigated.147 As shown in Figure 4B, illumination of guanine CL was confirmed to be dependent on the physical property of fluorescent dye emitted after receipt of energy from high-energy intermediate formed in the reaction of guanine and TMPG under the help of TPA relying on the CRET. The reaction between carboxyfluorescein (6-FAM) and TMPG emitted CL, which was utilized to develop an aptasensor for quantification of thrombin in human serum. The binding of thrombin and its aptamer was not emissive in guanine CL system, while dissociated 6FAM labeled aptamer immediately reacted with TMPG with bright light illuminated. The aptasensor showed a LOD of 12.3 nM in quantifying thrombin in 5% human serum. Very recently, the same group has constructed a cost-effective and easy-to-use aptasensor for the rapid quantification and monitoring of Escherichia Coli O157:H7.148 The binding complex of target and two terminal guanines in its aptamer reacted with TMPG to yield a high-energy intermediates. Then, 6-FAM was directly associated



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with the terminal guanines, emitting strong CL based on the intra-CRET. A LOD of 4.5×102 cfu/mL for Escherichia Coli O157:H7 was finally achieved. Nanostructures based strategies. With unique properties, the introduction of nanostructures into CL based biosensors infuses fresh blood in this field. Examples include mesoporous SiNPs (MSN) based controlled release system for CL detection of cocaine. The MSN substrate loaded with glucose interacted with negatively charged cocaine aptamer to occlude the mesopores on substrate.149 In presence of target, the binding of cocaine and its aptamer had high affinity and released entrapped glucose into the solution. Assisted by glucose oxidase (GOx), the released glucose reacted with the dissolved oxgen to generate gluconic acid and H2O2, of which the latter could enhance the CL of luminol in NaOH solution. The obtained LOD was 1.43 µM. Substantial application of this method came into reality by detecting cocaine in serum samples with high selectivity. As a derivative of isoluminol, N-(4-aminobutyl)-N-ethylisoluminol (ABEI) displayed high CL quantum efficiency after being chemically conjugated with specific nanomaterials such as Au nanoflowers (AuNFs), achieving highly sensitive detection of CAP.150 With a competitive format, the LODs were determined to be 0.01 ng/mL in buffer and 1 ng/mL in milk, respectively. The proposed method was employed to detect CAP in milk samples and comparison with a commercial ELISA method was also made. The contribution of high sensitivity of AuNFs and good overall stability of the CL bioassay helped to establish a promising approach for the detection of small molecular illegal additives. What is worth mentioning is the relationship between the catalytic performance of AuNPs for CL reaction and its morphology. The catalytic activity of aggregated AuNPs was found to be stronger than that of dispersed AuNPs in the luminol-H2O2 CL system. Hence, through exploration of the relationship between target-induced aptamers’ conformational change and AuNPs’ morphology change (from dispersed state to aggregated state), CL signal resulted from the AuNPs could sensitively detect target acetamiprid (Figure 4C).151 This assay strategy successfully signified both of the specificity of aptamers’ recognition and the sensitivity of AuNPs based CL analysis, with a LOD estimated to be 62 pM, far more sensitive than contemporary acetamiprid assays, holding a great potential for low level measurement of pesticide residues in early environmental monitoring and contamination management. 26 ACS Paragon Plus Environment

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COLORIMETRIC DETECTION Colorimetric sensors allow for direct observation of a color change when the target analytes are present. A significant advantage emerges accordingly: dependence on analytical instruments may be minimized or even eliminated, making on-site and real-time detection more manageable. So far, most of the reported colorimetric aptasensors still employ AuNPs and G-quadruplex/hemin DNAzyme as signal reporters. Dipstick colorimetric strategy is also included because of low-cost and fast diagnostics with good robustness, specificity, sensitivity and low limits of detection.152 AuNPs based colorimetry strategies. An extraordinary property belonging to AuNPs enables the wide application in construction of colorimetric assays, that is, the color change under different states of the solution: red as well-dispersed AuNPs solution is, the solution will transform into blue or purple when AuNPs are aggregated. Successful detection for ATP,153 sulfadimethoxine,154 pathogen DNA,155 cancer cells,156,157 and some freshly emerging targets such as okadaic acid (OA),158 urea,159 iprobenfos and edifenphos160 have been reported. A novel colorimetric aptasensor based on AuNPs for detecting Staphylococcus aureus by using tyramine signal amplification technology was reported (Figure 5A).161 The biotinylated aptamer was immobilized on avidin coated microplate. In presence of target, it could be captured by its aptamer. Then, plenty of catalase could bind to surface of the target under the aid of the tyramine signal amplified technology, leading to consumption of H2O2. Hence gold trichloric acid could be reduced into NPs in aggregation states (blue color) by low concentration of H2O2. In absence of the target, the concentration of H2O2 was high, and the formation of AuNPs occurred rapidly with no aggregation happening (red color). The detection sensitivity reached a LOD of 9 cfu/mL and a success in analysis in milk sample by this strategy was demonstrated, producing the results without significant difference between a classical plate counting method and the developed method.



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Previous report has proved the possibility for the watersoluble cationic polymers to exhibit a significant advantage in relation to the aggregation of AuNPs. As a substitution of salt, their incorporation into design of AuNPs based colorimetric biosensors makes them more sensitive than traditional salt-induced AuNPs aggregation strategy due to interactions between cationic polymer and DNA. Such a label-free based colorimetric assay was developed for ultrasensitive determination of thrombin.162 As shown in Figure 5B, in absence of thrombin, aptamer with randomly coiled structure interacted with cationic polymer, poly(diallyldimethylammonium chloride) (PDDA) via electrostatic interaction, forming a duplex structure. Thus no sufficient PDDA was remained to induce AuNPs aggregation. When thrombin existed, aptamer interacted with thrombin instead of with PDDA, leaving enough PDDA to induce AuNPs aggregation. The color change from wine-red to blue-purple was observable even by naked eye. The obtained LOD for thrombin was as low as 1 pM with high selectivity despite the existence of interference from other proteins. Likewise, Taqhdisi et al. realized fast detection of Pb2+ with a LOD of 702 pM only by altering PDDA to PEI.163 Detection of Pb2+ in real samples of human serum, rat serum and tap water was also attempted with decent results, suggesting great potential for diagnostic purposes. Niu et al. used multiple aptamers as stabilizer of AuNPs to fabricate a homogeneous multiplex aptasensor.164 Molecules of sulfadimethoxine (SDM), kanamycin (KAN) and adenosine (ADE) were chosen as targets with respective aptamer of KAN aptamer (750 nM), SDM aptamer (250 nM) and ADE aptamer (500 nM) mixed at a 1:1:1 volume ratio, which were adsorbed directly onto bare AuNPs surface by electrostatic interaction. Multiple target detection was thus realized, maintaining comparable sensitivity as a single-target aptasensor for each target individually. Relying on the principle of AuNPs aggregation, colorimetric aptasensors based on triple-helix molecular switch (THMS) have also been investigated.165 The aptasensor exhibited high selectivity toward tetracyclines with a LOD of 266 pM. Not only are AuNPs used as signal probes in colorimetric biosensors, but they also have application in visual detections of targets through direct catalytic reaction. For example, the catalytic amplification effect of AuNPs facilitated the establishment of visual detection of thrombin by a simple, cost-effective, and ultrasensitive colorimetric approach (Figure 5C).166 The sensing procedure started with immobilization of thiol-thrombin aptamers on AuNPs’ surface by Au-S interaction. The vacancy of thrombin made the yellow colored 4-nitrophenol approaching the AuNPs surface and changed into 28 ACS Paragon Plus Environment

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colorless 4-aminophenol. The introduction of thrombin generated aptamer-thrombin complex partly covering the AuNPs surfaces, leading to a delay in reaction time of 4-nitrophenol to 4-aminophenol. The resulted LOD was 0.1 nM with naked eye observation. The authors also demonstrated the detection of thrombin in human serum samples and the results kept agreement with those obtained by buffer colorimetric method. Peroxidase or mimetic peroxidase based colorimetry strategies. With the analogous function of the common peroxidase HRP,167,168 hemin functionalized reduced GO (hemin-rGO),169 the G-quadruplex/hemin DNAzyme,170-173 G-quadruplex/Cu(II) metalloenzyme174 and AuNPs175,176 could also catalyze the oxidation of 2,2-azino-bis-(3-ethylben-zthiazoline-6-sulfonic acid) (ABTS) or 3,3',5,5'-tetramethylbenzidine sulfate (TMB) in presence of H2O2 accompanied with color change. Miao et al. described an enzyme-linked polymer nanotracer by immobilization of both the dsDNA antibody and HRP labeled AuNPs on Envision reagents (dsDNA Ab/EV-AuNPs-HRP).167 This nanotracer acted as signal tag in sensitive and facile colorimetric aptasensor for detection of CAP (Figure 5D). Compared with typical single or several HRP linked immunohistochemistry reagent, this nanotracer has remarkable amplification effect for the enzyme-linked chromogenic reaction by the enormous HRPs in EV. Thus, the employment of EV reagent as a matrix prepared the enzyme linked polymer tracer with the purpose of reaching lower LOD. Experimental results suggested a LOD of 0.015 ng/mL of CAP detection. Moreover, CAP detection in the fish samples had consistent results with that of the ELISA, verifying its accuracy and reliability. Hemin can function as peroxidase to participate in design of colorimetric biosensors. Our group for the first time have described the simple wet-chemical strategy for synthesis of hemin-graphene hybrid nanosheets through π-π interactions.177 The resulted nanosheets own the ability of distinguishing ssDNA and dsDNA, and the peroxidase-like activity can catalyze the reaction of peroxidase substrate. The utilization of such attractive material contributes to the development of label-free colorimetric detection system for SNP in disease-associated DNA. Recently, Yang et al. carried out the detection of acetamiprid by a colorimetric method with the same material (Figure 5E).169 Different concentrations 29 ACS Paragon Plus Environment


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of acetamiprid were firstly incubated with aptamer. The amount of free aptamer adsorbed on the heminrGO surface was decreased with the increasing acetamiprid in the test solution, enabling the composites coagulate to a higher degree under the optimum NaCl concentration. Consequently, the decreased level of hemin-rGO in the supernatant after centrifugation catalyzed oxidation of TMB in presence of H2O2 to yield light blue color with a low absorbance. The color change has close relationship with the acetamiprid concentration and is judgeable by naked eye. A LOD of 40 nM was obtained through UVvisible spectrometer. This sensing platform has advantages of simple operation process and low-cost portable instrument. In recent time, G-quadruplex/Cu(II) metalloenzyme assembly formed by human telomeric DNA (5’G3(TTAG3)3-3’) and Cu2+ exhibited excellent peroxidase property tthat could catalyze the reaction of TMB and H2O2 to produce a high absorption peak at 652 nm wavelength.174 A label-free colorimetric sensing system for simultaneous detection of histidine and cysteine with high sensitivity and selectivity was described. As shown in Figure 5F, the presence of Cu2+ promoted the formation of Gquadruplex/Cu(II) metalloenzyme complex which exhibited high catalytic activity for oxidation of TMB in presence of H2O2. Owing to the high affinity with Cu2+, histidine and sulfur-containing cysteine can hinder the formation of the catalytic complex, thus lowering the catalytic activity. The ultimate LOD in experimental conditions was 10 nM and 5 nM for histidine and cysteine, respectively, both of which were superior to previous colorimetric arrays. N-ethylmaleimide (NEM) boosted the alkylation of cysteine, inhibiting the interaction between cysteine and Cu2+ with the selectivity assured. Our group have also contributed to the development of a label-free and enzyme-free three-input visual majority logic gate by only utilizing DNA hybridization but no DNA replacement or enzyme catalysis by the oxidation reaction between TMB and H2O2 under catalysis of G-quadruplex/hemin DNAzyme.178 Furthermore, a one-vote veto function was coordinated into the DNA-based majority logic gate, where one input had priority over other inputs. The developed system is compatible for multiple basic and cascade logic gates. Interestingly, the decision made by the DNA strands can not only be directly distinguished by naked eye but also be read by a fluorescence signal which may be used as a remote output signal. Dipstick based colorimetry strategies. 30 ACS Paragon Plus Environment

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The lateral flow technology is one reliable method that converts antibody-based assays to user-friendly test kits, a widely-known example is the pregnancy test kit. In spite of their wide applications in antibody assays, NAs based lateral flow devices (LFD) were designed in latest decades. These devices may possess all the expected characteristics for a biosensor, such as low detection limit, high sensitivity, good selectivity, small amount of sample and no washing steps required, robustness, low-cost, quick assay performance in just one step and a user-friendly format. Nanomaterials (e.g. AuNPs,179 CNTs,180 magnetic beads181) are usually regarded as labels in design and fabrication of colorimetric lateral flow strip (LFS). The applications of LFDs include detection of biomarkers,181,182 metal ions,183 pathogens in food,179 cells,71 etc.. An example can be cited by the description of a CNT-based LFD for quick detection of DNA sequence with high sensitivity.180 As shown in Figure 6A, amine-modified DNA detection probe was immobilized by covalent bond on the shortened multi-walled carbon nanotubes (MWCNTs). Sandwich-type DNA hybridization reactions occurred on the LFD and the captured MWCNTs on test zone and control zone of LFD yielded the characteristic black bands, facilitating visual detection of DNA sequences. The optimized LFD had the ability of detecting 0.1 nM target DNA with naked eye. The realization of quantitative detection could be attributed to record of the intensity of the test line with the Image J software. A LOD of 40 pM was obtained, 12.5 times lower than that of AuNPs-based LFD. In Qin et al. report, a strip biosensors array constructed by aptamer-modified AuNPs as receptors was built, making a combination of the protein-aptamer binding reaction, the streptavidin-biotin interaction and the sandwich format (Figure 6B).182 Only by naked eye could three proteins be distinguished without mutual interference, retaining low detection limit and wide linear range. A complete set of four elementary logic gates (AND, OR, INH, and NAND) and eight combinative logic gates (AND-OR; AND-INH; OR-INH; INH-NAND; AND-OR-INH; AND-INHNAND; OR-INH-NAND; AND-OR-INH-NAND) are thoroughly realized using this array, which could eventually be applicable to the keypad lock system with enhanced complexity in the near future. As is the case with LFS, introduction of other strips have also been attempted in fabrication of colorimetric NA sensors, such as GO@SiO2@CeO2 nanosheets (GSCs) based bioactive paper,184 polydiacetylene (PDA) strip185 and litmus test strip,186 owing to their unique optical properties that are readily distinguishable by naked eye. Li Group performed a litmus test for Escherichia coli detection, in which an RNA-cleaving DNAzyme acted as molecular recognition element and protein enzyme urease 31 ACS Paragon Plus Environment


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as signal transducer (Figure 6C).186 The urease has catalytic activity for hydrolysis of urea, raising the solution pH. By coupling urease to the DNAzyme on magnetic beads, the existence of bacteria was reflected by a pH increase, which can be readily detected using a litmus dye or pH paper. The simplicity, low-cost, and wide generality make this litmus test attractive for POC diagnotics.

SURFACE PLASMON RESONANCE (SPR) DETECTION The technique of SPR is also helpful and powerful tool for highly sensitive and label-free sensing to investigate biomolecular interactions. In SPR based NA sensors, surface plasmon polaritons work as a probe to monitor the interactions at the sensor surface by the change in refractive index. Their application in the detection of various biological analytes including pathogen DNA,187 micro RNA,188,189 proteins190,191 in recent years has been reported. Wang et al. reported an enzyme-free amplified SPR biosensor for microRNA detection based on coupling of AuNPs and

DNA

supersandwich.189 In the detection strategy, the DNA-modified AuNPs as the primary amplification element hybridized with the capture DNA on the Au film with amplification effect for SPR signal meanwhile initiated the following secondary amplification, i.e. DNA supersandwich formation of two report DNA probes. A lowest detectable concentration of miRNA was about 8 fM. Additionally, high selectivity regarding single-base mismatch was also shown in this assay with the suitableness for target analysis in human serum demonstrated. A first SPR aptasensor utilizing a plastic optical fiber (POF) to detect VEGF, a circulating protein possibly related with cancer, was fabricated.191 The developed system is easily accessible and can well conduct the development of a rapid, convenient and low-cost diagnostic platform, along with sensitivity in level of nanomolar (LOD of 0.8 nM). SPR imaging (SPRi) is an optical technique that monitors refractive index changes at the metal/dielectric media interface for label-free detection and analysis of biomolecular interactions. The target immobilization onto a thin metal-coated surface (mostly Au) is necessary for the assay and changes in refractive index at the interface between the metal surface and the medium of interaction are employed for detection process. A report stated that the combination of near-infrared (NIR) QDs and SPRi improved the LOD because of a mass loading effect and spontaneous emission coupling with 32 ACS Paragon Plus Environment

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propagating surface plasmons (Figure 7A).192 Execution of sandwich assay via the incorporation of QDs labeled aptamer made sensitive detection for 7 zeptomole (at 5 fg/mL) of C-reactive protein (CRP) in spiked human serum possible. The same group also reported 9 X-aptamers, which were selected for binding to P4.193 Taking advantage of the multi-array feature of SPRi, they fabricated an optimized biosensor, employing nanoEnhancers (NIR QDs) for ultrasensitive detection of P4. The designed assay had a LOD of 5 nM.

SURFACE-ENHANCED RAMAN SCATTERING (SERS) DETECTION As a Raman spectroscopy technique with nanoscale optical phenomena, SERS, has been utilized for qualitative and quantitative analysis and construction of fast, reliable, sensitive measurements. Numerous studies have been devoted to SERS-based biosensor assays in recent decades. Compared with normal Raman spectra, almost 104- to 106-fold enhancement is provided by SERS, which can be attributed to plasmon resonances of illuminated metallic substrates (such as gold and silver colloids) producing the random formation of localized plasmons or ‘‘hot spots’’ at the junctions. An aptasensor designed for ricin B chain (RTB) recognition was proposed by Zengin et al. which was based on AgNPs labeled with 4,4’-bipyridyl (Bpy, Raman reporter) and RTB aptamer.194 The LOD was reported to be 0.32 fM. What’s more, the detection ability of SERS aptasensor for detecting RTB in artificially contaminated orange juice, milk, blood and urine was also testified with the standard curves similar to the one obtained from buffer solution. Likewise, a similar SERS aptasensor for detection of Vibrio parahaemolyticus was reported with SiO2@AuNPs as substrate, Cy3-modified aptamer as the recognition element and Raman reporter. The LOD was as low as 10 cfu/mL under optimal conditions.195 A novel SERS-based lateral flow assay was developed to quantitatively analyze human immunodeficiency virus type 1 (HIV-1) DNA biomarker (Figure 7B).196 The DNA probes and Raman reporter (malachite green isothiocyanate (MGITC))-functionalized AuNPs were regarded as SERS nano tags, instead of using bare AuNPs in LFSs. Quantitative analysis of HIV-1 DNA with high sensitivity became possible by monitoring the characteristic Raman peak intensity of the DNA-conjugated AuNPs 33 ACS Paragon Plus Environment


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on the test line. The LOD of the SERS-based lateral flow assay was 0.24 pg/ml, at least 1000 times more sensitive than colorimetric or commercial fluorescent detection methods. A AuNPs-enhanced SERS aptasensor has been demonstrated aiming multiplex detection of Salmonella typhimurium and Staphylococcus aureus.197 The combination of AuNPs, Raman signal molecule and aptamers was used as the signal probe. Magnetic Fe3O4NPs were wrapped with gold and were immobilized with aptamers, which was used as capture probe. Quantitative detection relied on the record of Raman signal intensities. The resultant LOD was 35 cfu/mL and 15 cfu/mL for Staphylococcus aureus and Salmonella typhimurium, respectively. High sensitivity, good selectivity and short detection time were listed as the advantage of the method.

GRAVIMETRIC DETECTION. Gravimetric sensors (e.g. quartz crystal microbalance (QCM) sensors,198 microcantilever sensor,199,200 and leaky surface acoustic wave sensors (LSAW)201) employ the basic principle of a response to variation in mass. The usage of thin piezoelectric quartz crystals in most gravimetric sensors, is regarded either as resonating crystals (QCM), or as bulk/surface acoustic wave (SAW) devices. The binding behavior among biomolecules of DNAs, proteins or cells can generate a change in mass, giving a detectable signal proportional to the level of the target analyte in the sample. For example, a label-free microcantilever array aptasensor was reported with the purpose of detecting liver cancer cells by immobilizing HepG2 cells-specific TLS11a aptamers on the gold side of four microcantilevers (Figure 7C).199 The other four were backfilled by MCH and worked as reference microcantilevers to avoid the interference induced by the environment. The binding of aptamer-cell resulted in a change in the surface stress of the microcantilevers, compelling the microcantilevers to bend to the silicon side. High specificity was showed, not only towards human liver normal cells, but also other cancer cells like breast, bladder, and cervix tumors. The LOD was calculated to be 300 cells/mL. Another LSAW aptasensor for detecting human breast cancer cells was reported.201 The aptamer fixed on Au electrode surface of 100 MHz LiTaO3 piezoelectric crystal could effectively capture target cells (MCF-7 cells) by specific interaction between aptamer and the overexpressed MUC1 protein on tumor cell surface. The mass loading of LSAW aptasensor was increased by aptamer/cell complexes, leading to phase shifts of 34 ACS Paragon Plus Environment

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LSAW. The reported LOD was 32 cells/mL with excellent specificity and stability, and could be reproduced for ten times with no irreversible loss of activity.

OTHER DETECTION METHODS OF INTEREST Development for biosensor strategies is not confined to the transduction methods mentioned above, but some other strategies have also been included in recent years, such as biolayer interferometry (BLI),202 resonance Rayleigh scattering (RRS),203 field effect transistor (FET),204 optical magnetism,205 liquidcrystal (LC),206 dual polarization interferometry (DPI),207 magnetoresistance (MR),208 evanescent wave (EV) and so on. Targets categories cover metal ions, toxins, proteins and small molecules. In this part, some other representative strategies will be discussed in details. A label-free surface charge modulated aptasensor for lysozyme detection was proposed through the DNA-protein interaction inside a single glass conical nanopore (Figure 7D).209 The introduction of aptamer to nanopore channels imported a negatively charged surface. At pH 7.4, positively charged lysozyme (pI 11) specifically interacted with aptamers, partially neutralized the negative surface charge, leading to a sensitive change in the rectified ionic current passing through the membrane of the single conical nanopores. The change in ionic current of the single conical nanopore was regarded as a sign for covalent modification of aptamer and the recognition events. The LOD was 0.5 pM. The target range extension could be achieved by adjusting the pH to make sure the existence of opposite charge polarities between the protein molecules and corresponding aptamer. Bisphenol A (BPA) detection by a sensitive plasmonic chirality-based aptasensor was reported.210 The hybridization of a BPA aptamer (modified by 20 nm AuNPs) and its complementary sequence (modified by 10 nm AuNPs) generated asymmetric plasmonic nanoparticle dimers. In presence of BPA, the BPA aptamer preferably switch its configuration for combination with the BPA target. The AuNPs dimers were decomposed into dispersed NPs. This sensor had a low LOD (8 pg/mL) for detecting BPA. Importantly, this method was suitable for analysis of real samples with excellent recovery (93%-98.4%). Zhang et al. demonstrated the construction of a plasmonic core-satellite nanostructured assemblies on two-dimensional substrates, through the combination of DNA-functionalized AuNPs and the 35 ACS Paragon Plus Environment


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recognition ability toward specific target for self-assembling of satellite AuNPs (diameter 17 nm) around the core AuNPs (diameter 40 nm) fixed on substrates (Figure 7E).211 In presence of target, the extremely shortened distance between core and satellite AuNPs resulted in a strongly coupled plasmonic resonance band, which presented remarkable red-shift and strengthened extinction concerning the local SPR (LSPR) band of individual core AuNPs on the substrate. Moreover, the selectivity was so high that single-base mismatched DNA could be achieved by strongly coupled plasmonic core-satellite nanostructured assembly on a substrate. Such substrate-based detection exhibited its reusability and high cyclic stability by verification of five cycles of disassembly and reassembly. Simultaneous detection for a variety of targets is usually necessary because of the requirement for reducing the detection time and lowering the cost. As an example, Kowalczyk et al. reported a dual DNA electrochemical biosensor composed of two redox couples with poly(N-isopropylacrylamide-coacrylic acid) hydrogel (pNIPA) as sensing platform.212 Our group demonstrated a novel DNA three-way junction (TWJ) with three functional moieties, which integrated the electrochemical, fluorescent, and colorimetric properties.213 As shown in Figure 7F, under the excitation of external stimuli including DNA, thrombin and ATP, strand displacement reaction and conformation transformation would be induced by the specific interactions between targets and sensing elements. These result in the integration of G-quadruplex/hemin complex as electrochemical probe, lighting up the fluorescence of DNA/AgNCs and enhancing the catalytic activity of DNAzyme to catalyze the H2O2-TMB system to generate colorimetric signal. The utilization of this sensing platform for independent and simultaneous detection of three different kinds of targets was demonstrated. It was expected that the integration of TWJs would supply a typical model for creation of DNA junction nanostructures with more multiple functionalities for investigation of other biosensors with high sensitivity and selectivity. To improve the general methodology for developing aptasensors, Ellington Group developed a novel and robust kinetic competition strategy for aptasensor design.214 In their design, two oligo receptors, the aptamer and a molecular beacon competed for an antisense blocker in kinetics, contingently altered by pre-binding the target to the aptamer (Figure 7G). This “competitive” aptasensor showed a measured LOD of 30 nM with a fluorescence readout and as low as 3 nM for ricin toxin A-chain (RTA) detection 36 ACS Paragon Plus Environment

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on an electrochemical platform. The kinetic competition strategy has a more straightforward mechanism than the widely used antisense displacement strategy where an oligo kinetically competes with the target for binding instead of being released from a stable duplex. Because of its exemption from hybridization between the blocker and the aptamer, the strategy is considered to be novel and robust and have guiding significance for future aptamer design as its appropriateness in most aptamers, especially for the ones possessing too long sequences or too complicated secondary structures to be incorporated into the strategies based on target-induced conformational change.

TRENDS AND PERSPECTIVES NA plays a vital role in the biotechnological filed. Our focus in this review is the efforts devoted to constructions of biosensing mainly based on NA as molecular recognition element in recent years. Biosensors have progressed through 20 years of investigation, and for now, incorporation of new materials and implementation of DNA technology accelerate a further evolution of biosensors. Besides the pursuit for routine features and better performance like high stability, low-cost and ease in synthesis and modification, researchers would preferably devote more efforts in biosensors with high efficiency and substantial application. Thus it costs more attempt in technological innovation for optimization of the sensors to eliminate matrix effects in purpose of particular use with specificity and sensitivity. Additionally, there is no lack of designs with complicated amplification procedures. In these strategies, the complex constitution greatly limits their commercial launch although extremely high sensitivity is usually possessed for trace content of target in real sample analysis. While other traditional sensors that underwent performance improvement (like ratiometric biosensors64,109,139) have attracted increasing attention because the adaption of the strategies makes them more robust with more reliable analysis results, which is favorable for practical application. However, the commercialization of such biosensors is still limited owing to insufficiency of relevant technology for their manufacture at an affordable cost. Fortunately, by focusing on molecular transduction integrated into current biosensors rather than on the preparation of a wholly new sensing platform, the progress towards POC commercialization will be shortened and there exists the possibility for rapid tests devices (like personal glucose meter215,216 or pregnancy test kits217) that could promisingly be used for practical analysis. 37 ACS Paragon Plus Environment


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The research on in vitro detection has a greater deal than that of in vivo sensing. In spite of the superabundant studies of in vitro detection, sample preparation and extraction steps for NA still hinder the miniaturization of the sensing device. Most current systems are largely dependent on off-line sample preparation and reagent management, which means the object of sensing in most cases is restricted to spiked sample instead of the real one, thereby being unable to do routine home test. In terms of technical level, a restriction impeding their wide acceptance is the dubious suitability for detection of single analyte. The breakthrough for following generation of NA based sensing is simultaneous detection of multiple targets. In the aspect of multiplex detection, two powerful tools are worth mentioning: the microfluidic based sensing arrays and the logic sensing, the former of which has the capability of high-throughput analysis of complex sample whereas the latter desires the establishment of more complicated logic systems for intelligent estimation which is good for diagnosis in complexed systems. The appearance of biocomputers promotes the solution for the problems. These advanced sensors are constituted by basic sensing principles but are ingenious with groups of aptamer/target complexes or binding inhibitors. Despite the initial implementation of multiple analysis by biocomputers, researchers should always be aware that there is still a long way to go for practical application. Moreover，to survey all the available approaches comprehensively, none of them can meet all the requirements for any optional task. Hence, the investigation of strategies with good generality is another valued aspect. Some strategies reported can promisingly realize the generality, such as the THMS strategy by Tan Group,45 immobilization-free electrochemical strategy by Hsing Group,117 and kinetic competition strategy by Ellington Group.214 In THMS strategy, no labeling is required for the recognition sequence and one STP can be used for multiplex targets detection merely by changing different aptamers, sustaining the simplicity and cheapness of the STP synthesis. In immobilization-free electrochemical strategy, the general sensor works in homogeneous solution with a negatively charged bare ITO electrode, showing great potential to be integrated in simple, portable and cost-effective sensing devices. In kinetic competition strategy, aptamer modifications are not necessary, prefabricated molecular beacons can be used as the competitor, and all the sequences can be readily manipulated, showing the simplicity of constructing the reagents for the competition and modulating the competition mechanism. All these three strategies show the possibility to be adapted in different sensor platforms. 38 ACS Paragon Plus Environment

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For the three aforementioned newly emerging methods, the achievement of excellent stability and sensitivity is the crucial goal of imminent research. Another issue that needs to be specially mentioned is the biosensors based on aptamer and DNAzyme are commonly dependent on specific sequenced aptamer and specific secondary structured DNAzyme. For the field of fast developing aptasensors and DNAzyme sensors, a typical problem of deficiency in aptamer categories indeed exists. The number of user-friendly aptamers is so limited that 40% of the published works unlimitedly utilized the star aptamers (such as thrombin aptamer, ATP aptamer, cocaine aptamer etc.), reflecting the insufficiency in aptamers. Therefore, we have to mention the resultant problem of aptamer screening as the restrictive factor of this field. All the current exploration and screen for aptamer is equivalent to grope in the dark, because no solutions have been favorable although new screening methods have sprung up recently. Even so, aptamer development has already accomplished the examination of many important targets like oncogenic proteins, toxins, cells etc.. Aptasensors for a roughly estimated more than 100 targets have been reported. We should appreciate such advancement and put faith in increasing discovery of high-quality aptamer as the improvement in SELEX technology and the eventual application in the field of biosensing. In conclusion, it is still a research trend to establish simple, fast, stable, portable, low-cost, high throughput and miniaturized sensing strategies to realize complex target detection or even in vivo detection for target with ultra-low content. We expect that, as time goes by, commercial availability for NA sensors will ultimately come true, and will be highly potential for POC diagnostic.

CORRESPONDING AUTHOR *E-mail: [email protected].

NOTES The authors declare no competing financial interest.



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BIOGRAPHIES Yan Du studied chemistry at the Lanzhou University (China), where she received her B.S. degrees in 2006. Then, she joined Professor Shaojun Dong's group at the Changchun Institute of Applied Chemistry (China), and received her Ph.D. degree in 2011. From 2012-2013, she worked as a postdoctoral researcher in the Bioengineering School of Chemical and Biomedical Engineering at the Nanyang Technological University, (Singapore). From 2013-2016, she worked in Ellington Lab as a Postdoctoral Fellow at the University of Texas at Austin (USA). Her current research activities focuses on functional NA based biosensors, NA circuits (DNA computers) and gene diagnostics. Prof. Shaojun Dong is the professor of Chemistry in Changchun Institute of Applied Chemistry (CIAC) of the Chinese Academy of Sciences (CAS), and the Member of Academy of Sciences in the Developing World (TWAS). Her research interests concentrate in electrochemistry with interdisciplinary fields, such as: chemically modified electrodes, bioelectrochemistry, biosensors and

biofuel

cells,

spectroelectrochemistry,

ultramicroelectrode,

nanomaterials

and

nanotechnology. Her awards include: 1 International; 3 National Natural Science and 11 Advanced Science and Technology Awards from CAS and Jilin Province. She has Published over 900 papers in international SCI journals cited over 35,000 times with h-index 90. She is selected in the global “Highly Cited Researcher 2016” (2004-2016), in 2015 (2003-2013) and in 2014 (2002-2012) by ISI Web of Science (SCI) in the past 13 years.

ACKNOWLEDGMENT This work was supported by the National Natural Science Foundation of China (Nos. 21375123 and 21675151) and the Ministry of Science and Technology of China (Nos. 2013YQ170585 and 2016YFA0203201).

REFERENCES


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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


(1) Perumal, V.; Hashim, U. J. Appl. Biomed. 2014, 12, 1-15. (2) Sassolas, A.; Leca-Bouvier, B. D.; Blum, L. J. Chem. Rev. 2008, 108, 109-139. (3) Turner, A. P. F. Chem. Soc. Rev. 2013, 42, 3184-3196. (4) Teles, F. R. R.; Fonseca, L. R. Talanta 2008, 77, 606-623. (5) Li, D.; Song, S. P.; Fan, C. H. Acc. Chem. Res. 2010, 43, 631-641. (6) Drummond, T. G.; Hill, M. G.; Barton, J. K. Nat. Biotechnol. 2003, 21, 1192-1199. (7) Justino, C. I. L.; Rocha-Santos, T. A.; Duarte, A. C. TrAC, Trends Anal. Chem. 2010, 29, 1172-1183. (8) Pedrero, M.; Campuzano, S.; Pingarron, J. M. Sensors 2009, 9, 5503-5520. (9) Chen, J. C.; Shih, J. L.; Liu, C. H.; Kuo, M. Y.; Zen, J. M. Anal. Chem. 2006, 78, 3752-3757. (10) Wu, J. J.; Zhu, Y. Y.; Xue, F.; Mei, Z. L.; Yao, L.; Wang, X.; Zheng, L.; Liu, J.; Liu, G. D.; Peng, C. F.; Chen, W. Microchim. Acta 2014, 181, 479-491. (11) Du, Y.; Li, B. L.; Wang, E. K. Acc. Chem. Res. 2013, 46, 203-213. (12) Cho, E. J.; Lee, J. W.; Ellington, A. D. In Annu. Rev. Anal. Chem., 2009, pp 241-264. (13) Famulok, M.; Mayer, G. Acc. Chem. Res. 2011, 44, 1349-1358. (14) Lim, Y. C.; Kouzani, A. Z.; Duan, W. J. Biomed. Nanotechnol. 2010, 6, 93-105. (15) Mok, W.; Li, Y. F. Sensors 2008, 8, 7050-7084. (16) Liu, J. W.; Cao, Z. H.; Lu, Y. Chem. Rev. 2009, 109, 1948-1998. (17) Navani, N. K.; Li, Y. F. Curr. Opin. Chem. Biol. 2006, 10, 272-281. (18) Gong, L.; Zhao, Z. L.; Lv, Y. F.; Huan, S. Y.; Fu, T.; Zhang, X. B.; Shen, G. L.; Yu, R. Q. Chem. Commun. 2015, 51, 979-995. (19) Liu, J. W.; Lu, Y. J. Fluoresc. 2004, 14, 343-354. (20) Wang, F.; Lu, C. H.; Willner, I. Chem. Rev. 2014, 114, 2881-2941. (21) Willner, I.; Shlyahovsky, B.; Zayats, M.; Willner, B. Chem. Soc. Rev. 2008, 37, 1153-1165. (22) Ren, J.; Wang, T.; Wang, E.; Wang, J. Analyst 2015, 140, 2556-2572. (23) Chu, X.; Dou, X.; Liang, R.; Li, M.; Kong, W.; Yang, X.; Luo, J.; Yang, M.; Zhao, M. Nanoscale 2016, 8, 4127-4133. (24) Dai, S.; Wu, S.; Duan, N.; Wang, Z. Talanta 2016, 158, 246-253. (25) Teng, Y.; Jia, X.; Zhang, S.; Zhu, J.; Wang, E. Chem. Commun. 2016, 52, 1721-1724. (26) Hashemian, Z.; Khayamian, T.; Saraji, M.; Shirani, M. P. Biosens. Bioelectron. 2016, 79, 334-340. (27) Li, H.; Sun, D.-e.; Liu, Y.; Liu, Z. Biosens. Bioelectron. 2014, 55, 149-156. (28) Zhang, K.; Wang, K.; Zhu, X.; Xie, M. Biosens. Bioelectron. 2016, 78, 154-159. (29) Wang, H.-B.; Zhang, H.-D.; Chen, Y.; Liu, Y.-M. Biosens. Bioelectron. 2015, 74, 581-586. (30) Zhang, S.; Wang, L.; Liu, M.; Qiu, Y.; Wang, M.; Liu, X.; Shen, G.; Yu, R. Anal. Methods 2016, 8, 37403746. (31) Wang, K.; Ren, J.; Fan, D.; Liu, Y.; Wang, E. Chem. Commun. 2014, 50, 14390-14393. (32) Liu, H.; Wang, Y.-S.; Tang, X.; Yang, H.-X.; Chen, S.-H.; Zhao, H.; Liu, S.-D.; Zhu, Y.-F.; Wang, X.-F.; Huang, Y.-Q. J. Pharm. Biomed. Anal. 2016, 118, 177-182. (33) Ren, J.; Wang, J.; Wang, J.; Wang, E. Biosens. Bioelectron. 2014, 51, 336-342. (34) Qin, H.; Ren, J.; Wang, J.; Luedtke, N. W.; Wang, E. Anal. Chem. 2010, 82, 8356-8360. (35) Zhu, J.; Zhang, L.; Zhou, Z.; Dong, S.; Wang, E. Chem. Commun. 2014, 50, 3321-3323. (36) Zhu, J.; Zhang, L.; Zhou, Z.; Dong, S.; Wang, E. Anal. Chem. 2014, 86, 312-316. (37) Fu, T.; Ren, S.; Gong, L.; Meng, H.; Cui, L.; Kong, R.-M.; Zhang, X.-B.; Tan, W. Talanta 2016, 147, 302306.



1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Page 42 of 69

(38) Wei, Y.; Chen, Y.; Li, H.; Shuang, S.; Dong, C.; Wang, G. Biosens. Bioelectron. 2015, 63, 311-316. (39) Chen, Q.; Zuo, J.; Chen, J.; Tong, P.; Mo, X.; Zhang, L.; Li, J. Biosens. Bioelectron. 2015, 72, 326-331. (40) Guo, Y.; Chen, Y.; Wei, Y.; Li, H.; Dong, C. Spectrochim. Acta A Mol. Biomol. Spectrosc. 2015, 136, 16351641. (41) Chen, J.; Lin, J.; Zhang, X.; Cai, S.; Wu, D.; Li, C.; Yang, S.; Zhang, J. Anal. Chim. Acta 2014, 817, 42-47. (42) Wang, L.-j.; Zhang, Y.; Zhang, C.-y. Chem. Commun. 2014, 50, 15393-15396. (43) Zhou, Z.; Li, D.; Zhang, L.; Wang, E.; Dong, S. Talanta 2015, 134, 298-304. (44) Zhu, J.; Zhang, L.; Dong, S.; Wang, E. Chem. Sci. 2015, 6, 4822-4827. (45) Zheng, J.; Li, J.; Jiang, Y.; Jin, J.; Wang, K.; Yang, R.; Tan, W. Anal. Chem. 2011, 83, 6586-6592. (46) Verdian-Doghaei, A.; Housaindokht, M. R.; Abnous, K. Anal. Biochem. 2014, 466, 72-75. (47) Jalalian, S. H.; Taghdisi, S. M.; Danesh, N. M.; Bakhtiari, H.; Lavaee, P.; Ramezani, M.; Abnous, K. Anal. Methods 2015, 7, 2523-2528. (48) Li, Y.; Miao, X.; Ling, L. Sci. Rep. 2015, 5, 13010. (49) Apiwat, C.; Luksirikul, P.; Kankla, P.; Pongprayoon, P.; Treerattrakoon, K.; Paiboonsukwong, K.; Fucharoen, S.; Dharakul, T.; Japrung, D. Biosens. Bioelectron. 2016, 82, 140-145. (50) Xing, X.-J.; Xiao, W.-L.; Liu, X.-G.; Zhou, Y.; Pang, D.-W.; Tang, H.-W. Biosens. Bioelectron. 2016, 78, 431-437. (51) Wu, C.; Wang, K.; Fan, D.; Zhou, C.; Liu, Y.; Wang, E. Chem. Commun. 2015, 51, 15940-15943. (52) Zhou, C.; Wang, K.; Fan, D.; Wu, C.; Liu, D.; Liu, Y.; Wang, E. Chem. Commun. 2015, 51, 10284-10286. (53) Hu, K.; Huang, Y.; Wang, S. e.; Zhao, S. J. Pharm. Biomed. Anal. 2014, 95, 164-168. (54) Wei, Y.; Zhang, J.; Wang, X.; Duan, Y. Biosens. Bioelectron. 2015, 65, 16-22. (55) Li, C.; Meng, Y.; Wang, S.; Qian, M.; Wang, J.; Lu, W.; Huang, R. Acs Nano 2015, 9, 12096-12103. (56) Fang, Y.; Zheng, G.; Yang, J.; Tang, H.; Zhang, Y.; Kong, B.; Lv, Y.; Xu, C.; Asiri, A. M.; Zi, J.; Zhang, F.; Zhao, D. Angew. Chem. Int. Ed. 2014, 53, 5366-5370. (57) Fan, D.; Zhu, J.; Liu, Y.; Wang, E.; Dong, S. Nanoscale 2016, 8, 3834-3840. (58) Zhu, D.; Li, W.; Wen, H.-M.; Yu, S.; Miao, Z.-Y.; Kang, A.; Zhang, A. Biosens. Bioelectron. 2015, 74, 1053-1060. (59) Pang, Y.; Rong, Z.; Xiao, R.; Wang, S. Sci. Rep. 2015, 5, 9451. (60) Pang, Y.; Rong, Z.; Wang, J.; Xiao, R.; Wang, S. Biosens. Bioelectron. 2015, 66, 527-532. (61) Qian, J.; Wang, K.; Wang, C.; Hua, M.; Yang, Z.; Liu, Q.; Mao, H.; Wang, K. Analyst 2015, 140, 7434-7442. (62) Chen, Y.; Chen, L.; Ou, Y.; Wang, Z.; Fu, F.; Guo, L. Talanta 2016, 155, 245-249. (63) Chu-mong, K.; Thammakhet, C.; Thavarungkul, P.; Kanatharana, P.; Buranachai, C. Talanta 2016, 155, 305-313. (64) Fan, D.; Zhu, J.; Zhai, Q.; Wang, E.; Dong, S. Chem. Commun. 2016, 52, 3766-3769. (65) Chen, J.; Zhang, X.; Cai, S.; Wu, D.; Chen, M.; Wang, S.; Zhang, J. Biosens. Bioelectron. 2014, 57, 226-231. (66) Taghdisi, S. M.; Danesh, N. M.; Beheshti, H. R.; Ramezani, M.; Abnous, K. Nanoscale 2016, 8, 3439-3446. (67) Abnous, K.; Danesh, N. M.; Emrani, A. S.; Ramezani, M.; Taghdisi, S. M. Anal. Chim. Acta 2016, 917, 7178. (68) Miao, Y.-B.; Ren, H.-X.; Gan, N.; Cao, Y.; Li, T.; Chen, Y. Biosens. Bioelectron. 2016, 81, 454-459. (69) Cai, S.; Li, G.; Zhang, X.; Xia, Y.; Chen, M.; Wu, D.; Chen, Q.; Zhang, J.; Chen, J. Talanta 2015, 138, 225230. (70) Shrivastava, S.; Sohn, I.-Y.; Son, Y.-M.; Lee, W.-I.; Lee, N.-E. Nanoscale 2015, 7, 19663-19672.


Page 43 of 69

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


(71) Liang, L.; Su, M.; Li, L.; Lan, F.; Yang, G.; Ge, S.; Yu, J.; Song, X. Sens. Actuators, B: Chem. 2016, 229, 347-354. (72) Cao, S.-H.; Cai, W.-P.; Liu, Q.; Xie, K.-X.; Weng, Y.-H.; Huo, S.-X.; Tian, Z.-Q.; Li, Y.-Q. J. Am. Chem. Soc. 2014, 136, 6802-6805. (73) Jiang, H.-L.; Liu, X.-Y.; Qiu, Y.-x.; Yao, D.-S.; Xie, C.-F.; Liu, D.-L. Food Control 2015, 56, 202-210. (74) Eissa, S.; Siaj, M.; Zourob, M. Biosens. Bioelectron. 2015, 69, 148-154. (75) Zhao, Z.; Chen, H.; Ma, L.; Liu, D.; Wang, Z. Analyst 2015, 140, 5570-5577. (76) Fei, A.; Liu, Q.; Huan, J.; Qian, J.; Dong, X.; Qiu, B.; Mao, H.; Wang, K. Biosens. Bioelectron. 2015, 70, 122-129. (77) Elshafey, R.; Siaj, M.; Zourob, M. Biosens. Bioelectron. 2015, 68, 295-302. (78) Contreras Jimenez, G.; Eissa, S.; Ng, A.; Alhadrami, H.; Zourob, M.; Siaj, M. Anal. Chem. 2015, 87, 10751082. (79) Jo, H.; Kim, S.-K.; Youn, H.; Lee, H.; Lee, K.; Jeong, J.; Mok, J.; Kim, S.-H.; Park, H.-S.; Ban, C. Biosens. Bioelectron. 2016, 81, 80-86. (80) Kashefi-Kheyrabadi, L.; Mehrgardi, M. A.; Wiechec, E.; Turner, A. P. F.; Tiwari, A. Anal. Chem. 2014, 86, 4956-4960. (81) Wang, Y.; Feng, J.; Tan, Z.; Wang, H. Biosens. Bioelectron. 2014, 60, 218-223. (82) Sheng, Q.; Liu, R.; Zhang, S.; Zheng, J. Biosens. Bioelectron. 2014, 51, 191-194. (83) Peng, K.; Zhao, H.; Xie, P.; Hu, S.; Yuan, Y.; Yuan, R.; Wu, X. Biosens. Bioelectron. 2016, 81, 1-7. (84) Bogomolova, A.; Komarova, E.; Reber, K.; Gerasimov, T.; Yavuz, O.; Bhatt, S.; Aldissi, M. Anal. Chem. 2009, 81, 3944-3949. (85) Rivas, L.; Mayorga-Martinez, C. C.; Quesada-Gonzalez, D.; Zamora-Galvez, A.; de la Escosura-Muniz, A.; Merkoci, A. Anal. Chem. 2015, 87, 5167-5172. (86) Izadi, Z.; Sheikh-Zeinoddin, M.; Ensafi, A. A.; Soleimanian-Zad, S. Biosens. Bioelectron. 2016, 80, 582-589. (87) Tabrizi, M. A.; Shamsipur, M.; Farzin, L. Biosens. Bioelectron. 2015, 74, 764-769. (88) Zang, Y.; Lei, J.; Hao, Q.; Ju, H. Biosens. Bioelectron. 2016, 77, 557-564. (89) Li, M.; Zheng, Y.; Liang, W.; Yuan, Y.; Chai, Y.; Yuan, R. Chem. Commun. 2016, 52, 8138-8141. (90) Ma, Z.-Y.; Pan, J.-B.; Lu, C.-Y.; Zhao, W.-W.; Xu, J.-J.; Chen, H.-Y. Chem. Commun. 2014, 50, 1208812090. (91) Fan, L.; Zhao, G.; Shi, H.; Liu, M.; Wang, Y.; Ke, H. Environ. Sci. Technol. 2014, 48, 5754-5761. (92) Li, H.; Qiao, Y.; Li, J.; Fang, H.; Fan, D.; Wang, W. Biosens. Bioelectron. 2016, 77, 378-384. (93) Li, S.; Zhu, W.; Xue, Y.; Liu, S. Biosens. Bioelectron. 2015, 64, 611-617. (94) Yan, K.; Liu, Y.; Yang, Y.; Zhang, J. Anal. Chem. 2015, 87, 12215-12220. (95) Du, X.; Jiang, D.; Dai, L.; Zhou, L.; Hao, N.; Qian, J.; Qiu, B.; Wang, K. Biosens. Bioelectron. 2016, 81, 242-248. (96) Li, C.; Wang, H.; Shen, J.; Tang, B. Anal. Chem. 2015, 87, 4283-4291. (97) Salimi, A.; Khezrian, S.; Hallaj, R.; Vaziry, A. Anal. Biochem. 2014, 466, 89-97. (98) Zheng, Y.; Yuan, Y.; Chai, Y.; Yuan, R. Biosens. Bioelectron. 2015, 66, 585-589. (99) Wu, L.; Xiong, E.; Yao, Y.; Zhang, X.; Zhang, X.; Chen, J. Talanta 2015, 134, 699-704. (100) Mazloum-Ardakani, M.; Hosseinzadeh, L.; Taleat, Z. Biosens. Bioelectron. 2015, 74, 30-36. (101) Chen, L.; Sha, L.; Qiu, Y.; Wang, G.; Jiang, H.; Zhang, X. Nanoscale 2015, 7, 3300-3308. (102) Xu, W.; Xue, S.; Yi, H.; Jing, P.; Chai, Y.; Yuan, R. Chem. Commun. 2015, 51, 1472-1474.



1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Page 44 of 69

(103) Li, Y.; Deng, J.; Fang, L.; Yu, K.; Huang, H.; Jiang, L.; Liang, W.; Zheng, J. Biosens. Bioelectron. 2015, 63, 1-6. (104) Pei, H.; Lu, N.; Wen, Y.; Song, S.; Liu, Y.; Yan, H.; Fan, C. Adv. Mater. 2010, 22, 4754-4758. (105) Lin, M.; Song, P.; Zhou, G.; Zuo, X.; Aldalbahi, A.; Lou, X.; Shi, J.; Fan, C. Nat. Protocols 2016, 11, 1244-1263. (106) Dong, S.; Zhao, R.; Zhu, J.; Lu, X.; Li, Y.; Qiu, S.; Jia, L.; Jiao, X.; Song, S.; Fan, C.; Hao, R.; Song, H. ACS Appl. Mat. Interfaces 2015, 7, 8834-8842. (107) Ge, Z.; Lin, M.; Wang, P.; Pei, H.; Yan, J.; Sho, J.; Huang, Q.; He, D.; Fan, C.; Zuo, X. Anal. Chem. 2014, 86, 2124-2130. (108) Miao, P.; Wang, B.; Chen, X.; Li, X.; Tang, Y. ACS Appl. Mat. Interfaces 2015, 7, 6238-6243. (109) Du, Y.; Lim, B. J.; Li, B.; Jiang, Y. S.; Sessler, J. L.; Ellington, A. D. Anal. Chem. 2014, 86, 8010-8016. (110) Fan, C. H.; Plaxco, K. W.; Heeger, A. J. Proc. Natl. Acad. Sci. U S A. 2003, 100, 9134-9137. (111) Chen, X.; Gui, H.; Wei, B.; Wang, J. Mater. Sci. Semicond. Process. 2015, 35, 127-131. (112) Shen, W.-J.; Zhuo, Y.; Chai, Y.-Q.; Yuan, R. Anal. Chem. 2015, 87, 11345-11352. (113) Yu, P.; Liu, Y.; Zhang, X.; Zhou, J.; Xiong, E.; Li, X.; Chen, J. Biosens. Bioelectron. 2016, 79, 22-28. (114) Yu, P.; Zhou, J.; Wu, L.; Xiong, E.; Zhang, X.; Chen, J. J. Electroanal. Chem. 2014, 732, 61-65. (115) Gao, F.; Qian, Y.; Zhang, L.; Dai, S.; Lan, Y.; Zhang, Y.; Du, L.; Tang, D. Biosens. Bioelectron. 2015, 71, 158-163. (116) Jia, J.; Chen, H. G.; Feng, J.; Lei, J. L.; Luo, H. Q.; Li, N. B. Anal. Chim. Acta 2016, 908, 95-101. (117) Xuan, F.; Luo, X.; Hsing, I. M. Anal. Chem. 2012, 84, 5216-5220. (118) Tan, Y.; Wei, X.; Zhang, Y.; Wang, P.; Qiu, B.; Guo, L.; Lin, Z.; Yang, H.-H. Anal. Chem. 2015, 87, 11826-11831. (119) Tan, Y.; Wei, X.; Zhao, M.; Qiu, B.; Guo, L.; Lin, Z.; Yang, H.-H. Anal. Chem. 2015, 87, 9204-9208. (120) Tan, Y.; Qiu, J.; Cui, M.; Wei, X.; Zhao, M.; Qiu, B.; Chen, G. Analyst 2016, 141, 1121-1126. (121) Wang, X.; Dong, S.; Gai, P.; Duan, R.; Li, F. Biosens. Bioelectron. 2016, 82, 49-54. (122) Liu, S.; Kang, M.; Yan, F.; Peng, D.; Yang, Y.; He, L.; Wang, M.; Fang, S.; Zhang, Z. Electrochim. Acta 2015, 160, 64-73. (123) Liu, S.; Lin, Y.; Wang, L.; Liu, T.; Cheng, C.; Wei, W.; Tang, B. Anal. Chem. 2014, 86, 4008-4015. (124) Chen, Q.; Chen, H.; Zhao, Y.; Zhang, F.; Yang, F.; Tang, J.; He, P. Biosens. Bioelectron. 2014, 54, 547552. (125) Li, Z.; Sun, L.; Zhao, Y.; Yang, L.; Qi, H.; Gao, Q.; Zhang, C. Talanta 2014, 130, 370-376. (126) Lou, J.; Wang, Z.; Wang, X.; Bao, J.; Tu, W.; Dai, Z. Chem. Commun. 2015, 51, 14578-14581. (127) Liu, Z.; Zhang, W.; Qi, W.; Gao, W.; Hanif, S.; Saqib, M.; Xu, G. Chem. Commun. 2015, 51, 4256-4258. (128) Gui, G.-F.; Zhuo, Y.; Chai, Y.-Q.; Xiang, Y.; Yuan, R. Anal. Chem. 2014, 86, 5873-5880. (129) Li, G.; Yu, X.; Liu, D.; Liu, X.; Li, F.; Cui, H. Anal. Chem. 2015, 87, 10976-10981. (130) Liu, W.; Yang, H.; Ge, S.; Shen, L.; Yu, J.; Yan, M.; Huang, J. Sens. Actuators, B: Chem. 2015, 209, 32-39. (131) Ma, M.-N.; Zhang, X.; Zhuo, Y.; Chai, Y.-Q.; Yuan, R. Nanoscale 2015, 7, 2085-2092. (132) Ma, M.-N.; Zhuo, Y.; Yuan, R.; Chai, Y.-Q. Anal. Chem. 2015, 87, 11389-11397. (133) Wang, C.; Qian, J.; Wang, K.; Hua, M.; Liu, Q.; Hao, N.; You, T.; Huang, X. ACS Appl. Mat. Interfaces 2015, 7, 26865-26873. (134) Wu, D.; Xin, X.; Pang, X.; Pietraszkiewicz, M.; Holyst, R.; Sun, X. g.; Wei, Q. ACS Appl. Mat. Interfaces 2015, 7, 12663-12670.


Page 45 of 69

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


(135) Jin, G.; Wang, C.; Yang, L.; Li, X.; Guo, L.; Qiu, B.; Lin, Z.; Chen, G. Biosens. Bioelectron. 2015, 63, 166-171. (136) Zhang, P.; Wu, X.; Yuan, R.; Chai, Y. Anal. Chem. 2015, 87, 3202-3207. (137) Yang, L.; Tao, Y.; Yue, G.; Li, R.; Qin, B.; Guo, L.; Lin, Z.; Yang, H.-H. Anal. Chem. 2016, 88, 5097-5103. (138) Cheng, Y.; Huang, Y.; Lei, J.; Zhang, L.; Ju, H. Anal. Chem. 2014, 86, 5158-5163. (139) Lei, Y.-M.; Huang, W.-X.; Zhao, M.; Chai, Y.-Q.; Yuan, R.; Zhuo, Y. Anal. Chem. 2015, 87, 7787-7794. (140) Feng, X.; Gan, N.; Lin, S.; Li, T.; Cao, Y.; Hu, F.; Jiang, Q.; Chen, Y. Sens. Actuators, B: Chem. 2016, 226, 305-311. (141) Cai, S.; Tian, X.; Sun, L.; Hu, H.; Zheng, S.; Jiang, H.; Yu, L.; Zeng, S. Anal. Chem. 2015, 87, 1054210546. (142) Huang, X. Y.; Liang, Y. R.; Ruan, L. G.; Ren, J. C. Anal. Bioanal. Chem. 2014, 406, 5677-5684. (143) Wu, Q. W.; Shen, H. H.; Shen, H.; Sun, Y.; Song, L. F. Talanta 2016, 150, 531-538. (144) Bi, S.; Luo, B.; Ye, J.; Wang, Z. Biosens. Bioelectron. 2014, 62, 208-213. (145) Jo, E.-J.; Mun, H.; Kim, S.-J.; Shim, W.-B.; Kim, M.-G. Food Chem. 2016, 194, 1102-1107. (146) Song, Y. H.; Yang, X.; Li, Z. Q.; Zhao, Y. J.; Fan, A. P. Biosens. Bioelectron. 2014, 51, 232-237. (147) Cho, S.; Park, L.; Chong, R.; Kim, Y. T.; Lee, J. H. Biosens. Bioelectron. 2014, 52, 310-316. (148) Khang, J.; Kim, D.; Chung, K. W.; Lee, J. H. Talanta 2016, 147, 177-183. (149) Chen, Z. H.; Tan, Y.; Xu, K. F.; Zhang, L.; Qiu, B.; Guo, L. H.; Lin, Z. Y.; Chen, G. N. Biosens. Bioelectron. 2016, 75, 8-14. (150) Hao, L.; Duan, N.; Wu, S.; Xu, B.; Wang, Z. Anal. Bioanal. Chem. 2015, 407, 7907-7915. (151) Qi, Y.; Xiu, F.-R.; Zheng, M.; Li, B. Biosens. Bioelectron. 2016, 83, 243-249. (152) Quesada-Gonzalez, D.; Merkoci, A. Biosens. Bioelectron. 2015, 73, 47-63. (153) Huo, Y.; Qi, L.; Lv, X.-J.; Lai, T.; Zhang, J.; Zhang, Z.-Q. Biosens. Bioelectron. 2016, 78, 315-320. (154) Liu, J.; Guan, Z.; Lv, Z.; Jiang, X.; Yang, S.; Chen, A. Biosens. Bioelectron. 2014, 52, 265-270. (155) Jeong, J.; Kim, H.; Lee, D. J.; Jung, B. J.; Lee, J. B. Nanoscale Res. Lett. 2016, 11. (156) Borghei, Y.-S.; Hosseini, M.; Dadmehr, M.; Hosseinkhani, S.; Ganjali, M. R.; Sheikhnejad, R. Anal. Chim. Acta 2016, 904, 92-97. (157) Zhang, X.; Xiao, K.; Cheng, L.; Chen, H.; Liu, B.; Zhang, S.; Kong, J. Anal. Chem. 2014, 86, 5567-5572. (158) Gu, H.; Duan, N.; Wu, S.; Hao, L.; Xia, Y.; Ma, X.; Wang, Z. Sci. Rep. 2016, 6, 21665. (159) Kumar, P.; Lambadi, P. R.; Navani, N. K. Biosens. Bioelectron. 2015, 72, 340-347. (160) Kwon, Y. S.; Van-Thuan, N.; Park, J. G.; Gu, M. B. Anal. Chim. Acta 2015, 868, 60-66. (161) Yuan, J.; Wu, S.; Duan, N.; Ma, X.; Xia, Y.; Chen, J.; Ding, Z.; Wang, Z. Talanta 2014, 127, 163-168. (162) Chen, Z.; Tan, Y.; Zhang, C.; Yin, L.; Ma, H.; Ye, N.; Qiang, H.; Lin, Y. Biosens. Bioelectron. 2014, 56, 46-50. (163) Taghdisi, S. M.; Danesh, N. M.; Lavaee, P.; Ramezani, M.; Abnous, K. Environ. Toxicol. Pharmacol. 2015, 39, 1206-1211. (164) Niu, S.; Lv, Z.; Liu, J.; Bai, W.; Yang, S.; Chen, A. Plos One 2014, 9, e109263. (165) Ramezani, M.; Danesh, N. M.; Lavaee, P.; Abnous, K.; Taghdisi, S. M. Biosens. Bioelectron. 2015, 70, 181-187. (166) Chen, Z.; Tan, L.; Hu, L.; Zhang, Y.; Wang, S.; Lv, F. ACS Appl. Mat. Interfaces 2016, 8, 102-108. (167) Miao, Y.; Gan, N.; Li, T.; Zhang, H.; Cao, Y.; Jiang, Q. Sens. Actuators, B: Chem. 2015, 220, 679-687. (168) Gao, H.; Gan, N.; Pan, D.; Chen, Y.; Li, T.; Cao, Y.; Fu, T. Anal. Methods 2015, 7, 6528-6536.



1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Page 46 of 69

(169) Yang, Z.; Qian, J.; Yang, X.; Jiang, D.; Du, X.; Wang, K.; Mao, H.; Wang, K. Biosens. Bioelectron. 2015, 65, 39-46. (170) Wang, C.; Dong, X.; Liu, Q.; Wang, K. Anal. Chim. Acta 2015, 860, 83-88. (171) Wang, Q.; Yang, X.; Yang, X.; Liu, F.; Wang, K. Sens. Actuators, B: Chem. 2015, 212, 440-445. (172) Wu, S.; Wang, Y.; Duan, N.; Ma, H.; Wang, Z. J. Agric. Food. Chem. 2015, 63, 7849-7854. (173) Wang, S.; Bi, S.; Wang, Z.; Xia, J.; Zhang, F.; Yang, M.; Gui, R.; Li, Y.; Xia, Y. Chem. Commun. 2015, 51, 7927-7930. (174) Wu, C.; Fan, D.; Zhou, C.; Liu, Y.; Wang, E. Anal. Chem. 2016, 88, 2899-2903. (175) Taghdisi, S. M.; Danesh, N. M.; Lavaee, P.; Emrani, A. S.; Ramezani, M.; Abnous, K. RSC Adv. 2015, 5, 43508-43514. (176) Hu, J.; Ni, P.; Dai, H.; Sun, Y.; Wang, Y.; Jiang, S.; Li, Z. RSC Adv. 2015, 5, 16036-16041. (177) Guo, Y.; Deng, L.; Li, J.; Guo, S.; Wang, E.; Dong, S. ACS Nano 2011, 5, 1282-1290. (178) Fan, D.; Wang, K.; Zhu, J.; Xia, Y.; Han, Y.; Liu, Y.; Wang, E. Chem. Sci. 2015, 6, 1973-1978. (179) Fang, Z.; Wu, W.; Lu, X.; Zeng, L. Biosens. Bioelectron. 2014, 56, 192-197. (180) Qiu, W.; Xu, H.; Takalkar, S.; Gurung, A. S.; Liu, B.; Zheng, Y.; Guo, Z.; Baloda, M.; Baryeh, K.; Liu, G. Biosens. Bioelectron. 2015, 64, 367-372. (181) Wignarajah, S.; Suaifan, G. A. R. Y.; Bizzarro, S.; Bikker, F. J.; Kaman, W. E.; Zourob, M. Anal. Chem. 2015, 87, 12161-12168. (182) Qin, C.; Gao, Y.; Wen, W.; Zhang, X.; Wang, S. Biosens. Bioelectron. 2016, 79, 522-530. (183) Liu, J.; Chen, L.; Chen, J.; Ge, C.; Fang, Z.; Wang, L.; Xing, X.; Zeng, L. Anal. Methods 2014, 6, 20242027. (184) Deng, L.; Chen, C.; Zhu, C.; Dong, S.; Lu, H. Biosens. Bioelectron. 2014, 52, 324-329. (185) Wen, J. T.; Bohorquez, K.; Tsutsui, H. Sens. Actuators, B: Chem. 2016, 232, 313-317. (186) Tram, K.; Kanda, P.; Salena, B. J.; Huan, S.; Li, Y. Angew. Chem. Int. Ed. 2014, 53, 12799-12802. (187) Kaur, G.; Paliwal, A.; Tomar, M.; Gupta, V. Biosens. Bioelectron. 2016, 78, 106-110. (188) Ding, X.; Yan, Y.; Li, S.; Zhang, Y.; Cheng, W.; Cheng, Q.; Ding, S. Anal. Chim. Acta 2015, 874, 59-65. (189) Wang, Q.; Liu, R.; Yang, X.; Wang, K.; Zhu, J.; He, L.; Li, Q. Sens. Actuators, B: Chem. 2016, 223, 613620. (190) Lee, D.-W.; Park, K. M.; Gong, B.; Shetty, D.; Khedkar, J. K.; Baek, K.; Kim, J.; Ryu, S. H.; Kim, K. Chem. Commun. 2015, 51, 3098-3101. (191) Cennamo, N.; Pesavento, M.; Lunelli, L.; Vanzetti, L.; Pederzolli, C.; Zeni, L.; Pasquardini, L. Talanta 2015, 140, 88-95. (192) Vance, S. A.; Sandros, M. G. Sci. Rep. 2014, 4, 5129. (193) Zeidan, E.; Shivaji, R.; Henrich, V. C.; Sandros, M. G. Sci. Rep. 2016, 6, 26714. (194) Zengin, A.; Tamer, U.; Caykara, T. J. Mater. Chem. B 2015, 3, 306-315. (195) Duan, N.; Chang, B.; Zhang, H.; Wang, Z.; Wu, S. Int. J. Food Microbiol. 2016, 218, 38-43. (196) Fu, X.; Cheng, Z.; Yu, J.; Choo, P.; Chen, L.; Choo, J. Biosens. Bioelectron. 2016, 78, 530-537. (197) Zhang, H.; Ma, X.; Liu, Y.; Duan, N.; Wu, S.; Wang, Z.; Xu, B. Biosens. Bioelectron. 2015, 74, 872-877. (198) Shan, W.; Pan, Y.; Fang, H.; Guo, M.; Nie, Z.; Huang, Y.; Yao, S. Talanta 2014, 126, 130-135. (199) Chen, X.; Bai, X.; Li, H.; Zhang, B. RSC Adv. 2015, 5, 35448-35452. (200) Li, H.; Bai, X.; Wang, N.; Chen, X.; Li, J.; Zhang, Z.; Tang, J. Talanta 2016, 146, 727-731. (201) Chang, K.; Pi, Y.; Lu, W.; Wang, F.; Pan, F.; Li, F.; Jia, S.; Shi, J.; Deng, S.; Chen, M. Biosens. Bioelectron. 2014, 60, 318-324.


Page 47 of 69

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


(202) Gao, S.; Hu, B.; Zheng, X.; Cao, Y.; Liu, D.; Sun, M.; Jiao, B.; Wang, L. Biosens. Bioelectron. 2016, 79, 938-944. (203) Ren, W.; Zhang, Y.; Chen, H. G.; Gao, Z. F.; Li, N. B.; Luo, H. Q. Anal. Chem. 2016, 88, 1385-1390. (204) Wang, C.; Cui, X.; Li, Y.; Li, H.; Huang, L.; Bi, J.; Luo, J.; Ma, L. Q.; Zhou, W.; Cao, Y.; Wang, B.; Miao, F. Sci. Rep. 2016, 6, 21711. (205) Yang, J.; Donolato, M.; Pinto, A.; Bosco, F. G.; Hwu, E.-T.; Chen, C.-H.; Alstrom, T. S.; Lee, G.-H.; Schaefer, T.; Vavassori, P.; Boisen, A.; Lin, Q.; Hansen, M. F. Biosens. Bioelectron. 2016, 75, 396-403. (206) Khan, M.; Khan, A. R.; Shin, J.-H.; Park, S.-Y. Sci. Rep. 2016, 6, 22676. (207) Zheng, Y.; Hu, T.; Chen, C.; Yang, F.; Yang, X. Chem. Commun. 2015, 51, 5645-5648. (208) Sinha, B.; Ramulu, T. S.; Kim, K. W.; Venu, R.; Lee, J. J.; Kim, C. G. Biosens. Bioelectron. 2014, 59, 140144. (209) Cai, S.-L.; Cao, S.-H.; Zheng, Y.-B.; Zhao, S.; Yang, J.-L.; Li, Y.-Q. Biosens. Bioelectron. 2015, 71, 37-43. (210) Kuang, H.; Yin, H.; Liu, L.; Xu, L.; Ma, W.; Xu, C. ACS Appl. Mat. Interfaces 2014, 6, 364-369. (211) Zhang, T.; Li, H.; Hou, S.; Dong, Y.; Pang, G.; Zhane, Y. ACS Appl. Mat. Interfaces 2015, 7, 27131-27139. (212) Kowalczyk, A.; Wagner, B.; Karbarz, M.; Nowicka, A. M. Sens. Actuators, B: Chem. 2015, 208, 220-227. (213) Zhang, L.; Guo, S.; Zhu, J.; Zhou, Z.; Li, T.; Li, J.; Dong, S.; Wang, E. Anal. Chem. 2015, 87, 1129511300. (214) Du, Y.; Zhen, S. J.; Li, B. L.; Byrom, M.; Jiang, Y. S.; Ellington, A. D. Anal. Chem. 2016, 88, 2250-2257. (215) Xiang, Y.; Lu, Y. Nat. Chem. 2011, 3, 697-703. (216) Du, Y.; Hughes, R. A.; Bhadra, S.; Jiang, Y. S.; Ellington, A. D.; Li, B. Sci. Rep. 2015, 5, 11039. (217) Du, Y.; Pothukuchy, A.; Gollihar, J. D.; Armin NouranI, A.; Li, B.; Ellington, A. D. Angew. Chem. Int. Ed. 2016. (218) Fang, L.-X.; Cao, J.-T.; Huang, K.-J. J. Electroanal. Chem. 2015, 746, 1-8. (219) Lee, H.-E.; Kang, Y. O.; Choi, S.-H. Int. J. Electrochem. Sci. 2014, 9, 6793-6808. (220) Shakoori, Z.; Salimian, S.; Kharrazi, S.; Adabi, M.; Saber, R. Anal. Bioanal. Chem. 2015, 407, 455-461. (221) Huang, H.; Bai, W.; Dong, C.; Guo, R.; Liu, Z. Biosens. Bioelectron. 2015, 68, 442-446. (222) Wang, K.; Lei, Y.; Zhong, G.-X.; Zheng, Y.-J.; Sun, Z.-L.; Peng, H.-P.; Chen, W.; Liu, A.-L.; Chen, Y.-Z.; Lin, X.-H. Biosens. Bioelectron. 2015, 71, 463-469. (223) Tang, W.; Zhu, G.; Liang, L.; Zhang, C.-Y. Analyst 2015, 140, 5936-5943. (224) Lan, J.; Liu, Y.; Li, L.; Wen, F.; Wu, F.; Han, Z.; Sun, W.; Li, C.; Chen, J. Sci. Rep. 2016, 6, 24813. (225) Peng, H.-P.; Hu, Y.; Liu, P.; Deng, Y.-N.; Wang, P.; Chen, W.; Liu, A.-L.; Chen, Y.-Z.; Lin, X.-H. Sens. Actuators, B: Chem. 2015, 207, 269-276. (226) Yang, L.; Li, X.; Yan, S.; Wang, M.; Liu, P.; Dong, Y.; Zhang, C. Anal. Methods 2015, 7, 5303-5310. (227) Pan, H.-z.; Yu, H.-w.; Wang, N.; Zhang, Z.; Wan, G.-c.; Liu, H.; Guan, X.; Chang, D. J. Biotechnol. 2015, 214, 133-138. (228) Tak, M.; Gupta, V.; Tomar, M. Biosens. Bioelectron. 2014, 59, 200-207. (229) Tabrizi, M. A.; Shamsipur, M. Biosens. Bioelectron. 2015, 69, 100-105. (230) Olcer, Z.; Esen, E.; Ersoy, A.; Budak, S.; Kaya, D. S.; Gok, M. Y.; Barut, S.; Ustek, D.; Uludag, Y. Biosens. Bioelectron. 2015, 70, 426-432. (231) Torati, R.; Reddy, V.; Yoon, S. S.; Kim, C. Biosens. Bioelectron. 2016, 78, 483-488. (232) Hou, L.; Jiang, L.; Song, Y.; Ding, Y.; Zhang, J.; Wu, X.; Tang, D. Microchim. Acta 2016, 183, 1971-1980. (233) Liu, M.; Yu, J.; Ding, X.; Zhao, G. Electrochem. Commun. 2016, 28, 161-168.



1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Page 48 of 69

(234) Guo, X.; Wen, F.; Zheng, N.; Luo, Q.; Wang, H.; Wang, H.; Li, S.; Wang, J. Biosens. Bioelectron. 2014, 56, 340-344. (235) Shi, Z.-Y.; Zheng, Y.-T.; Zhang, H.-B.; He, C.-H.; Wu, W.-D.; Zhang, H.-B. Electrochem. Commun. 2015, 27, 1097-1103. (236) Emrani, A. S.; Taghdisi, S. M.; Danesh, N. M.; Jalalian, S. H.; Ramezani, M.; Abnous, K. Anal. Methods 2015, 7, 3814-3818. (237) Alvarez-Martos, I.; Ferapontova, E. E. Anal. Chem. 2016, 88, 3608-3616. (238) Shandost-fard, F.; Roushani, M. J. Electroanal. Chem. 2016, 763, 18-24. (239) Yang, F.; Wang, P.; Wang, R.; Zhou, Y.; Su, X.; He, Y.; Shi, L.; Yao, D. Biosens. Bioelectron. 2016, 77, 347-352. (240) Niu, X.; Huang, L.; Zhao, J.; Yin, M.; Luo, D.; Yang, Y. Anal. Methods 2016, 8, 1091-1095. (241) Wang, Y.; Gao, D.; Zhang, P.; Gong, P.; Chen, C.; Gao, G.; Cai, L. Chem. Commun. 2014, 50, 811-813. (242) Zhao, J.; Guo, W.; Pei, M.; Ding, F. Anal. Methods 2016, 8, 4391-4397. (243) Danesh, N. M.; Ramezani, M.; Emrani, A. S.; Abnous, K.; Taghdisi, S. M. Biosens. Bioelectron. 2016, 75, 123-128. (244) Yan, Z.; Gan, N.; Wang, D.; Cao, Y.; Chen, M.; Li, T.; Chen, Y. Biosens. Bioelectron. 2015, 74, 718-724. (245) Hu, Y.; Li, L.; Guo, L. Sens. Actuators, B: Chem. 2015, 209, 846-852. (246) Qureshi, A.; Gurbuz, Y.; Niazi, J. H. Sens. Actuators, B: Chem. 2015, 220, 1145-1151. (247) Wu, Z.; Li, H.; Liu, Z. Sens. Actuators, B: Chem. 2015, 206, 531-537. (248) Ahirwar, R.; Nahar, P. Anal. Bioanal. Chem. 2016, 408, 327-332. (249) Meirinho, S. G.; Dias, L. G.; Peres, A. M.; Rodrigues, L. R. Biosens. Bioelectron. 2015, 71, 332-341. (250) Li, H.; Zhang, W.; Zhou, H. Anal. Biochem. 2014, 449, 26-31. (251) Formisano, N.; Jolly, P.; Bhalla, N.; Cromhout, M.; Flanagan, S. P.; Fogel, R.; Limson, J. L.; Estrela, P. Sens. Actuators, B: Chem. 2015, 220, 369-375. (252) Ji, K.; de Carvalho, L. P.; Bi, X.; Seneviratnankn, A.; Bhakoo, K.; Chan, M.; Li, S. F. Y. Biosens. Bioelectron. 2014, 55, 405-411. (253) Jo, H.; Gu, H.; Jeon, W.; Youn, H.; Her, J.; Kim, S.-K.; Lee, J.; Shin, J. H.; Ban, C. Anal. Chem. 2015, 87, 9869-9875. (254) Kumar, L. S. S.; Wang, X.; Hagen, J.; Naik, R.; Papautsky, I.; Heikenfeld, J. Anal. Methods 2016, 8, 34403444. (255) Miodek, A.; Castillo, G.; Hianik, T.; Korri-Youssoufi, H. Biosens. Bioelectron. 2014, 56, 104-111. (256) Majidi, M. R.; Omidi, Y.; Karami, P.; Johari-Ahar, M. Talanta 2016, 150, 425-433. (257) Zhao, F.; Xie, Q.; Xu, M.; Wang, S.; Zhou, J.; Liu, F. Biosens. Bioelectron. 2015, 66, 238-243. (258) Farid, S.; Meshik, X.; Choi, M.; Mukherjee, S.; Lan, Y.; Parikh, D.; Poduri, S.; Baterdene, U.; Huang, C.E.; Wang, Y. Y.; Burke, P.; Dutta, M.; Stroscio, M. A. Biosens. Bioelectron. 2015, 71, 294-299. (259) Trashin, S.; de Jong, M.; Breugelmans, T.; Pilehvar, S.; De Wael, K. Electrochem. Commun. 2015, 27, 3237. (260) Matharu, Z.; Patel, D.; Gao, Y.; Hague, A.; Zhou, Q.; Revzin, A. Anal. Chem. 2014, 86, 8865-8872. (261) Erdem, A.; Congur, G. Colloids Surf. B Biointerfaces 2014, 117, 338-345. (262) Stepanova, V. B.; Shurpik, D. N.; Evtugyn, V. G.; Stoikov, I. I.; Evtugyn, G. A.; Osin, Y. N.; Hianik, T. Sens. Actuators, B: Chem. 2016, 225, 57-65. (263) Liu, J.; Lai, T.; Mu, K.; Zhou, Z. Analyst 2014, 139, 4874-4878. (264) Chen, Z.; Zhang, C.; Li, X.; Ma, H.; Wan, C.; Li, K.; Lin, Y. Biosens. Bioelectron. 2015, 65, 232-237.


Page 49 of 69

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


(265) Biyani, M.; Kawai, K.; Kitamura, K.; Chikae, M.; Biyani, M.; Ushijima, H.; Tamiya, E.; Yoneda, T.; Takamura, Y. Biosens. Bioelectron. 2016, 84, 120-125. (266) Chen, X.; Pan, Y.; Liu, H.; Bai, X.; Wang, N.; Zhang, B. Biosens. Bioelectron. 2016, 79, 353-358. (267) Wang, T.; Liu, J.; Gu, X.; Li, D.; Wang, J.; Wang, E. Anal. Chim. Acta 2015, 882, 32-37. (268) Yuan, B.; Zhou, Y.; Guo, Q.; Wang, K.; Yang, X.; Meng, X.; Wan, J.; Tan, Y.; Huang, Z.; Xie, Q.; Zhao, X. Chem. Commun. 2016, 52, 1590-1593. (269) Zhu, W.; Li, Z.; Liu, X.; Yan, X.; Deng, L. Anal. Lett. 2015, 48, 2870-2881. (270) Wu, W.; Zhao, S.; Mao, Y.; Fang, Z.; Lu, X.; Zeng, L. Anal. Chim. Acta 2015, 861, 62-68. (271) Queiros, R. B.; Gouveia, C.; Fernandes, J. R. A.; Jorge, P. A. S. Biosens. Bioelectron. 2014, 62, 227-233. (272) Feng, X.; Gan, N.; Zhang, H.; Yan, Q.; Li, T.; Cao, Y.; Hu, F.; Yu, H.; Jiang, Q. Biosens. Bioelectron. 2015, 74, 587-593. (273) Yan, K.; Wang, R.; Zhang, J. Biosens. Bioelectron. 2014, 53, 301-304. (274) Zhou, Q.; Rahimian, A.; Son, K.; Shin, D.-S.; Patel, T.; Revzin, A. Methods 2016, 97, 88-93.



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TABLE Table 1. Examples of DNA sensors for detection of various targets. Target

Method

Signal transduction

Limit of detection (LOD)

Influenza virus (H7N9)

DNA tetrahedral nanostructure as probe

electrochemistry (EC)

100 fM


gold nanoparticles (AuNPs), graphene and flowerlike VS2 modified glassy carbon electrode as platform

EC

52 fM


AuNPs modified carbon electrode as platform

EC

0.1 pM

Human immunodeficiency virus type 1 (HIV-1)

surface-enhanced Raman scattering (SERS)-based lateral flow assay

surface-enhanced Raman scattering (SERS); colorimetry

0.24 pg/mL

Hepatitis (HBV)

gold nanorods (AuNRs) as amplification element

EC

2 pM

EC

40.3 fM

EC

0.35 pM

Tan et al. (2015)119

EC

47 fM

Wang et al. (2015)222

5.3 aM

Tang et al. (2015)223

40 aM

Lan et al. (2016)224

EC

2.95 pM

Peng et al. (2015)225

electrochemiluminescence (ECL)

0.02 fM

Yang et al. (2016)137

EC

72.1 fM

Yang et al. (et al.)226

B

virus

Human papilloma virus (HPV) Oral cancer overexpressed 1 (ORAOV1) Acute promyelocytic leukemia (APL) Lung cancer cell H460 genomic DNA Breast cancer overexpressed c-erbB-2 oncogene Multidrug resistance (MDR1) gene P53 tumor suppressor gene Thermolabile hemolysin

graphene/AuNRs/polythionine modified electrode as platform combining the signal amplification of nicking endonuclease assisted target recycling and the immobilization-free electrochemical method Y junction structure and restriction endonuclease assisted cyclic enzymatic amplification combining endonuclease MscI and a single base extension reaction to distinct differentiate the mutant target ExoIII-assisted target cycles and long-range selfassembly DNA concatamers as dual signal amplification elements AuNPs/toluidine blue-graphene oxide (GO) modified electrode as platform cascade signal amplification of nicking endonuclease assisted target recycling and hyperbranched rolling circle amplification (HRCA) carboxyl-functionalized GO (CFGO) and singlewalled carbon nanotubes (SWCNTs) sensing platform

fluorescence resonance energy transfer (FRET) upconversion luminescence (UCL)

Klebsiella pneumoniae carbapenemase (KPC)

AuNPs and graphene modified electrode as platform

EC

0.2 pM

Neisseria meningitides

flower-like ZnO nanostructures modified electrode as platform

EC

5 ng/µL

Salmonella

label-free impedimetric DNA nanoporous glassy carbon electrode

EC

0.15 pM

microfluidics and nanoparticles based amperometric method

EC

6 pM

HRP-mimicking G-quadruplex/hemin wrapped GOx nanocomposites as tag

EC

0.01 nM

gold nanotubes array (AuNTsA) as platform

EC

0.05 ng/µL

dodecyltrimethylammonium bromide (DTBA)-coated transmission electron microscopy (TEM) grid cell as platform

liquid-crystal

0.05 nM

Cyanobacteria (Planktothrix agardhii NIVA-CYA 116) Escherichia coli O157:H7 Mycobacterium tuberculosis Erwinia carotovora Rhazictonia solani

sensor

based

DNAzyme

Reference Dong et al. 2015106 Fang et al. (2015)218 Lee et al. (2014)219 Fu et al. (2016)196 Shakoori et al. (2015)220 Huang et al. (2015)221

Pan et al. (2015)227 Tak et al. (2014)228 Tabrizi et al. (2015)229 Olcer et al. (2015)230 Li et al. (2015)103 Torati et al. (2016)231 Khan et al. (2016)206


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Table 2. Examples of aptasensors for detecting various targets. Method

Signal transduction

Limit of detection (LOD)

Reference

target-induced conformational change

EC

0.38 nM

Hou et (2016)232

al.

EC

4 pg/mL

Tan et (2015)118

al.

photoelectrochemistry (PEC)

0.5 fM

al.

label-free impedimetric aptasensor

EC

10 pg/mL

real-time quantitative PCR amplification

fluorescence

25 fg/mL

optics

50 pg/mL

colorimetry

0.01 ng/mL

fluorescence; EC

3 nM

AgNPs enhanced raman intensity

SERS

0.32 fM

Liu et (2016)233 Jiang et (2015)73 Guo et (2014)234 Gao et (2016)202 Gu et (2016)158 Du et (2016)214 Zengin et (2015) 194

AuNPs and graphene/thionine nanocomposites (GSTH) as electrode platform

EC

1 pg/mL

Shi et (2015)235

al.

Brevetoxins (BTXs)


EC

106 pg/mL

Eissa et (2015)74

al.

Lipopolysaccharid e (LPS)

Cu-based metal-organic frameworks (CuMOFs) as a catalyst and target-triggered quadratic cycles for signal amplification

EC

0.33 fg/mL

Shen et (2015)112

al.


EC

117 pg/mL


EC

0.5 nM

Digoxin

based on SiNPs coated with streptavidin

fluorescence

566 pM

Dopamine

exploiting an alkanethiol-conjugated dopamine aptamer tethered to the cysetamine-modified Au electrodes

EC

62 nM

Ibuprofen (IBP)

using water soluble CdTe QDs as the efficient electrochemical platform

EC

16 pM

Zhao et al. (2015)75 Elshafey et al. (2015)77 Emrani et al. (2015)236 AlvarezMartos et al. (2016)237 Shandost-fard et al. (2016)238

EC

0.5 pM

Yang et al. (2016)239

EC

0.3 pM

Niu et (2016)240

EC

0.21 nM

Sheng et al. (2014)82

EC

42 pM

Chen et (2015)101

FRET

0.6 pM

Wang et al. (2014)241

FRET

45 pM

Li et (2014)27

Target Saxitoxin (STX) Ochratoxin (OTA)

Toxins

A

Microcystins (MCs) Versicolorin A (VerA) Aflatoxin B1 (AFB1) Gonyautoxin 1/4 (GTX1/4) Okadaic acid (OA) Ricin A Chain (RTA) Ricin B Chain (RTB) Fumonisin (FB1)

B1

Cylindrospermops in (CYN) Anatoxin-A (ATX)

Ractopamine (RAC) Drugs Codeine Cocaine Lysozyme

Insulin Antibiotics

Kanamycin (CAP)

discrimination of the aggregation of long and short DNA on a negatively charged indium tin oxide (ITO) electrode Graphene modified onto TiO2 nanotubes surface as platform

label-free and real-time optical biolayer interferometry (BLI) aptasensor direct competitive enzyme-linked aptamer assay (ELAA) new aptasensing strategy relies on kinetic competition

using special immobilization media consisting of AuNPs/poly dimethyl diallyl ammonium chloride-graphene composite (AuNPs/PDDA-GN) AuNPs/polyamidoamine dendrimermodified screen printed carbon electrode as platform based on the 3D-DNA structure conversion of nanostructure based on hybridization chain reactions (HCR) and catalysis of silver nanoclusters near infrared quantum dots (NIR QDs) and oxidized carbon NPs (OCNPs) as the energy donor and acceptor, respectively upconversion nanoparticles (UCNPs) and graphene as the energy donor and

al. al. al. al. al. al.

al.

al.

al.



1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

oxytetracycline (OTC) Chloramphenicol (CAP) Penicillin

Streptomycin (STR) Acetamiprid Insecticides

Polychlorinated biphenyls (PCBs) Iprobenfos (IBF) Edifenphos (EDI) Cell-surface mucin1 (MUC1) Vascular endothelial growth factor (VEGF165) Anterior gradient homolog 2 (AGR2) Human epidermal growth factor receptor 2 (HER2) Carcinoembryonic antigen (CEA)

Tumor markers

acceptor, respectively p-type semiconductor BiOI doped with graphene as photoactive species ratiometric array on one SPCE substance composite film consisting of a magnetic graphene nanocomposite and a poly(3,4ethylenedioxythiophene)-AuNPs composite as the platform based on Exo I, complimentary strand of aptamer (CS), Arch shape structure of aptamer (Apt)-CS conjugate and Au electrode aggregated AuNPs’ catalytic capability for luminol-H2O2 CL reaction metal ions-loaded spherical branched polyethylene imine brushes (SPEIs) as tracers AuNPs based colorimetric aptasensor Cy3-labeled ssDNA probe stacked on the surface of oxidized mesoporous carbon nanospheres (OMCN) label-free impedimetric aptasensor based ordered mesoporous carbon-gold nanocomposite modified screen printed electrode based on AuNPs and magnetic separation label-free capacitance based aptasensor using interdigitated Au microelectrode (IDE) based capacitor arrays UCNPs as the energy donor and carbon NPs (CNPs) as the acceptor

Nucleolin

label-free detection

Estrogen receptor alpha (ERα) Osteopontin (OPN) Tumor necrosis factor-alpha (TNF-α) A-fetoprotein (AFP)

label-free AuNPs aptasensor

Prostate-specific antigen (PSA)

based

colorimetric

based on a screen-printed strip electrode bimetallic Ag@Pt core-shell NPs supported on reduced GO nanosheets as sensor platform base-stacking-dependent DNA hybridization assay on the optimisation of an EIS aptamerbased sensor by using quartz crystal microbalance with dissipation mode

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Yan et (2015) 94 Feng et (2016)140

al.

0.057 ng/mL

Zhao et (2016)242

al.

EC

11.4 nM

Danesh et al. (2016)243

ECL

62 pM

Qi et (206)151

al.

EC

0.3 pg/mL

Yan et (2015)244

al.

colorimetry

5 nM 10 nM

Kwon et al. (2015)160

fluorescence

6.52 nM

Li et (2015)55

EC

1.0 pg/mL

Tabrizi et al. (2015)87

optics

6.6 pM

Hu et (2015)245

EC

0.2 ng/mL

Qureshi et al. (2015)246

FRET

0.1 ng/mL

microcantilever

1.0 nM

colorimetry

0.64 ng/mL

EC

3.7 nM

EC

2.07 pg/mL

EC

2 pg/mL

EC

7 pM

Formisano et al. (2015)251 Pang et (2015)60

al.

Wang et (2015)171 Ji et (2014)252 Peng et (2106)83 Jo et (2015)253

al.

PEC

0.9 nM

ECL

0.03 nM

EC

Recombinant hemagglutinin (rHA) of H5N1 virus

based on the high fluorescence enhancement ability of the core-shell Ag@SiO2NPs

metal-enhanced fluorescence (MEF)

2 ng/mL

Myoglobin

based on hemin/G-quadruplex DNAzyme functionalized AuNPs

colorimetry

2.5 nM

target induced strand displacement

colorimetry

6.96 fM

EC

7 pM

EC

1 pM

fluorescence

50 µg/mL

Thrombospondin1 Nuclear factor kappa B (NF-κB) Cardiac troponin I (cTnI) Glycated human serum albumin (GHSA)

peroxidase-like mimic coupled DNA nanoladders for signal amplification ferrocene-modified SiNPs as electrochemical probe fluorescent quenching GO and Cy5labeled aptamer

al.

al.

al.

Wu et al. (2015)247 Li et al. (2016)200 Ahirwar et al. (2016)248 Meirinho et al. (2015)249 MazloumArdakani et al. (2015)100 Li et al. (2014)250

al. al. al.

Apiwat et al. (2016)49


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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


Interleukin-6 (IL6) C-reactive protein (CRP) Human cellular prions protein (PrPC) Interleukin-17 receptor A (IL17RA) L-tryptophan (Trp)

EC

0.02 pg/mL

Kumar et al. (2016)254

Surface plasmon resonance imaging

5 fg/mL

Vance et al. (2014)192

EC

0.8 pM

Miodek et al. (2014)255


EC

2.13 pg/mL

Jo et (2016)79

label-free aptasensor based Au screen printed electrode modified with multiwall carbon nanotube (MWCNT-AuSPE) electrode

EC

4.9 pM

Majidi et al. (2016)256

label-free impedimetric enhanced by AuNPs

EC

50 pM

Zhao et (2015)257

EC

83 pM

EC

~120 nM

EC

1 ng/mL

EC

0.74 µg/mL

EC

0.90 ng/mL

EC

0.02 nM

PEC

33 fM

Fan et (2014)91

al.

colorimetry

10 fM

Liu et (2014)263

al.

ECL

2.0×10-15 M

Li et (2014)125

al.

chemiluminescence (CL)

1.6 pg/mL

Bi et (2014)144

al.

fluorescence

140 nM

Wei et (2015)38

al.

EC

0.02 pM

Wang et al. (2014)81

EC

6 pM

EC

0.064 pM

EC

300 ng/mL

Biyani et al. (2016)265

2 cells/mL

KashefiKheyrabadi et al. (2014)80

32 cells/mL

Chang et al. (2014)201

polyprrole modified dendrimers as platform

with

redox

Cyclic adenosine monophosphate (cAMP) Interferon-gamma (IFN-γ) Peanut allergen Ara h 1 Transforming growth factor-beta 1 (TGF-β1) Human activated protein C (APC)

cell-culture/biosensor platform integrated with reconfigurable microfluidics for monitoring of transforming target impedimetric aptasensor based on poly(amidoamine) (PAMAM) dendrimer

Progesterone (P4)


Cytochrome c 17β-estradiol (E2) Biomarkers Nerve growth factor (NGF)

Thrombin Platelet-derived growth factor (PDGF-BB) Adenosine triphosphate (ATP) Adenosine Immunoglobulin E (IgE) Angiogenin

Renin

Cells

label-free impedimetric aptasensor enhanced by AuNPs combination of the SPRi platform with microwave assisted surface chemistry, aptamer technology and NIR QDs

graphene monolayer-based structure as platform

aptasensor FET-like


electropolymerized neutral red (Poly-NR) as electrochemical probe anti-E2 aptamer as the biorecognition element was developed onto CdSemodified TiO2 nanotube arrays visual detection approach based on a molecular translator and a catalytic DNA circuit employing ruthenium complex as ECL label and auxiliary probe as fixer to immobilize the dissociative Ru probe onto the electrode surface cascade autocatalytic recycling amplification (Exo-CARA) strategy assisted by Exo III for amplification using berberine as the fluorescence probe and Exo I as the digesting nuclease dithiothreitol (DTT) and 6mercaptohexanol (MCH) on Au electrode surface serve as dual backfillers enzyme-linked aptamer in the sandwich assay method and thionine as redox probe PDDA-functionalized graphene/AuNPs composites as amplification elements one-step competitive assay using disposable electrochemical printed chip and USB powered portable potentiostat system

HepG2 cells


EC

Michigan cancer foundation-7 (MCF-7)

2 × 3 model of leaky surface acoustic wave (LSAW) aptasensor array

leaky acoustic (LSAW)

surface wave

al.

al.

Farid et al. (2015)258 Trashin et al. (2015)259 Matharu et al. (2014)260 Erdem et al. (2014)261 Contreras Jimenez et al. (2015)78 Stepanova et al. (2016)262

Salimi et al. (2014)97 Chen et al. (2015)264



1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

T-cell acute lymphoblastic leukemia cells (CCRFCEM cells) Human Liver Hepatocellular Carcinoma Cells (HepG2)

HL-60 cells

Pathogenic Bacterias

colorimetry

40 cells

Zhang et al. (2014)157

label-free aptasensor

microcantilever

300 cells/mL

Chen et (2016)266

10 cells/mL 70 cells/mL 65 cells/mL 100 cells/mL

Wang et al. (2015)267

microcantilever

array

by

layer

EC

colorimetry

K562 cells

multiplexed monitoring of cancer cells in microfluidic paper-based analytical devices

SMMC-7721 cells

signal-on split aptasensor

FRET

Vibrio parahaemolyticus

with SiO2@AuNPs as substrate, Cy3modified aptamer as the recognition element and Raman reporter

SERS

Salmonella typhimurium Staphylococcus aureus

AuNPs enhanced Raman intensity

SERS 15 cfu/mL

Shigella flexneri coli

Escherichia coli outer membranes proteins (EcOMPs) Malachite (MG)

green

Streptavidin (SA) o-aminophenol (OAP) Bisphenol (BPA) Trinitrotoluene (TNT) Urea

Exosome

10 cfu/mL 35 cfu/mL

Bacillus cereus

Escherichia O157:H7

Other targets

cell-triggered cyclic enzymatic signal amplification

constructed though layer assembly technique (LBL)

Hela cells

Page 54 of 69

A

AuNPs modified pencil graphite electrode (PGE) as platform dye-labeled aptamer and GO using target recycling amplification amplified by isothermal strand displacement amplification (SDA) and further detected using lateral flow assay long period gratings refractometric platform

(LPGs)

as

a

dual-potential aptasensor array fabricated on a homemade screen-printed carbon electrode polyT-templated CuNPs as fluorescent probe assembling CdSe QDs and DNA on liquid phase deposited TiO2 (DNACdSe/TiO2) film electrode asymmetric plasmonic nanoparticle dimers based on bilayer structure of luminescence functionalized graphene hybrids non-enzymatic easy-to-use, dual readout aptasensor that exploits unmodified AuNPs to transduce the signals target induced displacement

al.

Liang et al. (2016)71 Yuan et al. (2016)268 Duan et al. (2016)195 Zhang et al. (2015)197 Izadi et (2016)86 Zhu et (2015)269

al.

10 cfu/mL

Wu et (2015)270

al.

evanescent wave

0.1 nM

Queiros et al. (2014)271

ECL

0.03 nM

Feng et (2015)272

fluorescence

0.1 nM

Wang et al. (2015)29

PEC

80 nM

Yan et (2014)273

plasmon

0.008 ng/mL

Kuang et al. (2014)210

ECL

0.63 pg/mL

Li et (2015)129

fluorescence; colorimetry

20 mM

Kumar et al. (2015)159

EC

106 particles/ mL

Zhou et (2016)274

EC

9.4 pM

fluorescence

100 cfu/mL

colorimetry

al.

al.

al.

al.

al.


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FIGURES AND CAPTIONS Figure 1. Examples of the fluorescent strategies. (A) Ultratrace detection of terbium (III) based on structural conversion of G-quadruplex DNA meditated by ThT and terbium (III). Reprinted from Biosens. Bioelectron., Vol. 321−322, Chen, Q.; Zuo, J. F.; Chen, J. F.; Tong, P.; Mo, X. J.; Zhang, L.; Li, J. R. A label-free fluorescent biosensor for ultratrace detection of terbium (ш) based on structural conversion of G-quadruplex DNA mediated by ThT and terbium (ш), pp. 326−331 (ref 39). Copyright 2015, with permission from Elsevier.39 (B) Design scheme of THMS for signaling aptamer-target binding event. Reproduced from Zheng, J.; Li, J. H.; Jiang, Y.; Jin, J. Y.; Wang, K. M.; Yang, R. H.; Tan, W. H. Anal. Chem., 2011, 83, 6586–6592 (ref 45). Copyright 2011 American Chemical Society.45 (C) Schematic illustration of the sensing principle based on the OMCN. Reproduced from Li, C. Y.; Wang, S. S.; Qian, M.; Wang, J. X.; Lu, W. Y., Huang, R. Q. ACS Nano, 2015, 9, 12096–12103 (ref 55). Copyright 2015 American Chemical Society.55 (D) Detecting of H5N1 virus by core-shell NPs MEF. Reprinted from Biosens. Bioelectron., Vol. 66, Pang, Y.; Rong, Z.; Wang, J.; Xiao, R.; Wang, S. A fluorescent aptasensor for H5N1 influenza virus detection based-on the core–shell NPs metalenhanced fluorescence (MEF), pp. 527−532 (ref 60). Copyright 2015, with permission from Elsevier.60 (E) Scheme of a cascade logic device for label-free ratiometric target DNA detection. Reproduced from Fan, D.; Zhu, J.; Zhai, Q.; Wang, E.; Dong, S. Chem. Commun., 2016, 52, 3766-3769 (ref 64), with permission of The Royal Society of Chemistry.64 (F) Detecting CAP by using DIL-encapsulated liposome as nanotracer. Reprinted from Biosens. Bioelectron., Vol. 81, Miao, Y.-B.; Ren, H.-X.; Gan, N.; Cao, Y.; Li, T.; Chen, Y. Fluorescent aptasensor for CAP detection using DIL-encapsulated liposome as nanotracer, pp. 454−459 (ref 68). Copyright 2016, with permission from Elsevier.68 (G) Schematic illustration of multiplexed monitoring of cancer cells in microfluidic paper-based analytical devices. Reprinted from Sensor Actuat. B-Chem., Vol. 229, Liang, L.; Su, M.; Li, L.; Lan, F.; Yang, G.; Ge, S.; Yu, J.; Song, X. Aptamer-based fluorescent and visual biosensor for multiplexed monitoring of cancer cells in microfluidic paper-based analytical devices, pp. 347−354 (ref 71). Copyright 2016, with permission from Elsevier. 71



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Figure 2. Examples of electrochemical strategies. (A) EIS aptasensor for sensitive detection of adenosine with dual backfillers. Reprinted from Biosens. Bioelectron., Vol. 60, Wang, Y.; Feng, J.; Tan, Z.; Wang, H. Electrochemical impedance spectroscopy aptasensor for ultrasensitive detection of adenosine with dual backfillers, pp. 218−223 (ref 81). Copyright 2014, with permission from Elsevier.81 (B) The PEC biosensor for detecting DNA by HCR amplification. Reproduced from Li, C.; Wang, H.; Shen, J.; Tang, B. Anal. Chem. 2015, 87, 4283 (ref 96). Copyright 2015 American Chemical Society.96 (C) Fabrication process of the electrochemical amplified determination of lysozyme based on HCR and catalysis of DNA/AgNCs. Reproduced from Chen, L.; Sha, L.; Qiu, Y.; Wang, G.; Jiang, H.; Zhang, X. Nanoscale 2015, 7, 3300-3308 (ref 101), with permission of The Royal Society of Chemistry.101 (D) Detecting of H7N9 virus by using a tetrahedral nanostructure probe-based DNA sensor. Reproduced from Dong, S.; Zhao, R.; Zhu, J.; Lu, X.; Li, Y.; Qiu, S.; Jia, L.; Jiao, X.; Song, S.; Fan, C.; Hao, R.; Song, H. ACS Appl. Mater. Interfaces 2015, 7, 8834 (ref 106). Copyright 2015 American Chemical Society.106 (E) Schematic view of the DNA based biosensor that relies on a ratiometric reporter. Reproduced from Du, Y.; Lim, B. J.; Li, B.; Jiang, Y.S.; Sessler, J. L.; Ellington, A. D. Anal. Chem., 2014, 86, 8010–8016 (ref 109). Copyright 2014 American Chemical Society.109 (F) Schematic view of a immobilization-free, signal-amplified electrochemical DNA detection strategy. Reproduced from Xuan, F.; Luo, X.; Hsing, I. M. Anal. Chem., 2012, 84, 5216 (ref 117). Copyright 2014 American Chemical Society.117


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Figure 3. Examples of electrochemiluminescence strategies. (A) Schematic illustration of the aptamer/SWCNH ECL biosensor for ATP detection. Reproduced from Liu, Z.; Zhang, W.; Qi, W.; Gao, W.; Hanif, S.; Saqib, M.; Xu, G. Chem. Commun., 2015, 51, 4256-4258 (ref 127), with permission of The Royal Society of Chemistry.127 (B) Schematic illustration of the ECL aptasensor preparation process and the possible luminescence mechanism. Reproduced from Ma, M.-N.; Zhang, X.; Zhuo, Y.; Chai, Y.-Q.; Yuan, R. Nanoscale 2015, 7, 2085-2092 (ref 131), with permission of The Royal Society of Chemistry.131 (C) DNAzyme-assisted target recycling and RCA for ultrasensitive detection of microRNS. Reproduced from Zhang, P.; Wu, X.; Yuan, R.; Chai, Y. Anal. Chem., 2015, 87, 3202–3207 (ref 136). Copyright 2015 American Chemical Society.136 (D) Schematic representation of ratiometric ECL strategy triggered by Mg2+-dependent DNAzyme for biosensing. Reproduced from Cheng, Y.; Huang, Y.; Lei, J.; Zhang, L.; Ju, H. Anal. Chem., 2014, 86, 5158–5163 (ref 138). Copyright 2014 American Chemical Society.138



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Figure 4. Examples of chemiluminescence strategies. (A) The schematic view of detecting PDGF by Exo-assisted cascade autocatalytic recycling amplification. Reprinted from Biosens. Bioelectron., Vol. 62, Bi, S.; Luo, B.; Ye, J.; Wang, Z. Label-free chemiluminescent aptasensor for PDGF-BB detection based on Exo-assisted cascade autocatalytic recycling amplification, pp. 208−213 (ref 144). Copyright 2014, with permission from Elsevier.144 (B) Rapid and simple G-quadruplex DNA aptasensor with guanine CL detection. Reprinted from Biosens. Bioelectron., Vol. 52, Cho, S.; Park, L.; Chong, R.; Kim, Y. T.; Lee, J. H. Rapid and simple G-quadruplex DNA aptasensor with guanine chemiluminescence detection, pp. 310−316 (ref 147). Copyright 2014, with permission from Elsevier.147 (C) Schematic illustration of the CL assay for acetamiprid detection by the catalytic performance of AuNPs. Reprinted from Biosens. Bioelectron., Vol. 83, Qi, Y. Y.; Xiu, F.-R.; Zheng, M. F.; Li, B. X. A simple and rapid chemiluminescence aptasensor for acetamiprid in contaminated samples: Sensitivity, selectivity and mechanism, pp. 243−249 (ref 151). Copyright 2016, with permission from Elsevier.151


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Figure 5. Examples of colorimetric strategies. (A) Schematic illustration of the detection of Staphylococcus aureus based on tyramine signal amplification. Reprinted from Talanta, Vol. 127, Yuan, J.; Wu, S.; Duan, N.; Ma, X.; Xia, Y.; Chen, J.; Ding, Z.; Wang, Z. A sensitive gold nanoparticle-based colorimetric aptasensor for Staphylococcus aureus, pp. 163−168 (ref 161). Copyright 2014, with permission from Elsevier.161 (B) Schematic representation of the detection of thrombin based on cationic polymer and AuNPs. Reprinted from Biosens. Bioelectron., Vol. 56, Chen, Z. B.; Tan, Y.; Zhang, C. M.; Yin, L.; Ma, H.; Ye, N. S.; Qiang, H.; Lin, Y. Q. A colorimetric aptamer biosensor based on cationic polymer and AuNPs for the ultrasensitive detection of thrombin, pp. 46−50 (ref 162). Copyright 2014, with permission from Elsevier.162 (C) Ultrasensitive thrombin detection by the catalytic amplification of AuNPs. Reproduced from Chen, Z.; Tan, L.; Hu, L.; Zhang, Y.; Wang, S.; Lv, F. ACS Appl. Mater. Interfaces, 2016, 8, 102–108 (ref 166). Copyright 2016 American Chemical Society.166 (D) Scheme of depicting the detecting CAP using dsDNA antibody labeled enzyme-linked polymer nanotracers. Reprinted from Sensor Actuat. B-Chem., Vol. 220, Miao, Y.; Gan, N.; Li, T.; Zhang, H.; Cao, Y.; Jiang, Q. A colorimetric aptasensor for CAP in fish based on double-stranded DNA antibody labeled enzyme-linked polymer nanotracers for signal amplification, pp. 679−687 (ref 167). Copyright 2015, with permission from Elsevier.167 (E) Illustration of the detecting acetamiprid by heminfunctionalized rGO. Reprinted from Biosens. Bioelectron., Vol. 65, Yang, Z.; Qian, J.; Yang, X.; Jiang, D.; Du, X.; Wang, K.; Mao, H.; Wang, K. A facile label-free colorimetric aptasensor for acetamiprid based on the peroxidase-like activity of hemin-functionalized reduced graphene oxide, pp. 39−46 (ref 169). Copyright 2015, with permission from Elsevier.169 (F) Detection of histidine and cysteine based on G-Quadruplex-Cu(II) metalloenzyme. Reproduced from Wu, C.; Fan, D.; Zhou, C.; Liu, Y.; Wang, E. Anal. Chem., 2016, 88, 2899–2903 (ref 174). Copyright 2016 American Chemical Society.174



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Figure 6. Examples of dipstick based colorimetric strategies. (A) Schematic illustration of the DNA measurement by MWCNT-based lateral flow strip. Reprinted from Biosens. Bioelectron., Vol. 64, Qiu, W.; Xu, H.; Takalkar, S.; Gurung, A. S.; Liu, B.; Zheng, Y.; Guo, Z.; Baloda, M.; Baryeh, K.; Liu, G. Carbon nanotube-based lateral flow biosensor for sensitive and rapid detection of DNA sequence, pp. 367−372 (ref 180). Copyright 2015, with permission from Elsevier.180 (B) Detection of Escherichia coli by using a litmus test strip. Reproduced from Translating Bacterial Detection by DNAzymes into a Litmus Test, Tram, K.; Kanda, P.; Salena, B. J.; Huan, S.; Li, Y. Angew. Chem. Int. Ed. Engl., Vol. 53, Issue 47 (ref 186). Copyright 2014 Wiley.186


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Figure 7. Other strategies. (A) QDs amplified SPRi aptasensor for detecting CRP. Reprinted with permission from ref 191. Copyright 2014 Nature Publishing Group.192 (B) The measurement principle of the SERS-based lateral flow assay for quantification of HIV-1 DNA. Reprinted from Biosens. Bioelectron., Vol. 78, Fu, X.; Cheng, Z.; Yu, J.; Choo, P.; Chen, L.; Choo, J. A SERS-based lateral flow assay biosensor for highly sensitive detection of HIV-1 DNA, pp. 530−537 (ref 196). Copyright 2016, with permission from Elsevier.196 (C) Microcantilever array aptasensor for detection of fumonisin B-1. Reproduced from Chen, X.; Bai, X.; Li, H.; Zhang, B. RSC Adv., 2015, 5, 35448-35452 (ref 199), with permission of The Royal Society of Chemistry.199 (D) Schematic description of the covalent modification procedures of glass nanopore surface with lysozyme aptamer. Reprinted from Biosens. Bioelectron., Vol. 71, Cai, S.-L.; Cao, S.-H.; Zheng, Y.-B.; Zhao, S.; Yang, J.-L.; Li, Y.-Q. Surface charge modulated aptasensor in a single glass conical nanopore, pp. 37−43 (ref 209). Copyright 2015, with permission from Elsevier.209 (E) Illustration of the construction of a plasmonic core−satellite nanostructure by DNA based self-assembly procedure. Reproduced from Zhang, T.; Li, H.; Hou, S.; Dong, Y.; Pang, G.; Zhane, Y. ACS Appl. Mater. Interfaces, 2015, 7, 27131–27139 (ref 211). Copyright 2015 American Chemical Society.211 (F) Schematic illustration of the TWJ-based platform for multifunctional DNA, thrombin and ATP analysis. Reproduced from Zhang, L.; Guo, S.; Zhu, J.; Zhou, Z.; Li, T.; Li, J.; Dong, S.; Wang, E. Anal. Chem., 2015, 87, 11295–11300 (ref 213). Copyright 2015 American Chemical Society.213 (G) Schematic illustration of “Kinetic Competition” aptasensor. Reproduced from Du, Y.; Zhen, S. J.; Li, B. L.; Byrom, M.; Jiang, Y. S.; Ellington, A. D. Anal. Chem., 2016, 88, 2250-2257 (ref 214). Copyright 2016 American Chemical Society.214



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Figure 1 180x113mm (300 x 300 DPI)

ACS Paragon Plus Environment

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Figure 2 180x139mm (300 x 300 DPI)



1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Figure 3 180x85mm (300 x 300 DPI)


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Figure 4 180x91mm (300 x 300 DPI)



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Figure 5 180x129mm (300 x 300 DPI)


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Figure 6 180x65mm (300 x 300 DPI)



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Figure 7 180x97mm (300 x 300 DPI)


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TOC 46x46mm (300 x 300 DPI)


Nucleic Acid Biosensors: Recent Advances and Perspectives

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