Enediol-Ligands-Encapsulated Liposomes Enables Sensitive

Letter

Enediol-Ligands-Encapsulated Liposomes Enables Novel Immunoassay: A Proof-of-Concept for General Liposomes-Based Photoelectrochemical Bioanalysis Li-Ping Mei, Fei Liu, Jianbin Pan, Wei-Wei Zhao, Jing-Juan Xu, and Hong-Yuan Chen Anal. Chem., Just Accepted Manuscript • Publication Date (Web): 08 Jun 2017 Downloaded from http://pubs.acs.org on June 8, 2017

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Analytical Chemistry

Enediol-Ligands-Encapsulated Liposomes Enables Novel Immunoassay: A Proof-of-Concept for General Liposomes-Based Photoelectrochemical Bioanalysis Li-Ping Mei,† Fei Liu,† Jian-Bin Pan,† Wei-Wei Zhao,*,†,‡ Jing-Juan Xu† and Hong-Yuan Chen*,† †

State Key Laboratory of Analytical Chemistry for Life Science and Collaborative Innovation Center of

Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China. ‡

Department of Materials Science and Engineering, Stanford University, Stanford, California 94305,

United States

* To whom correspondence should be addressed. * E-mail: [email protected]; [email protected] * E-mail: [email protected]

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Abstract: Sensitive photoelectrochemical (PEC) bioanalysis usually relies on enzyme-assisted signal amplification. This work describes the first proof-of-concept study for liposome-based PEC bioanalysis. Specifically, unilamellar liposomes were prepared and then utilized to carry the enediol-ligands and antibodies within their internal cavities and upon their external surfaces, respectively. On the other hand, the 96-well plate was used for accommodating the sandwich immunocomplexing, and then the confined liposomes were directed to release the encapsulated enediol-ligands into individual well. The subsequent in situ sensitization of the TiO2 nanoparticles (NPs) electrode was then used to transduce the recognition events. This facile strategy allows for sensitive immunoassay without the involvement of laborious electrode fabrication and enzymatic amplification. Importantly, the protocol can be extended as a general PEC method for numerous other targets of interest. We believe this work could offer a new perspective for the rational implementation of various liposome complexes for novel PEC bioanalysis. Keywords: Photoelectrochemical; Immunoassay; Liposomes; Enediol-ligands; TiO2 electrode


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This work describes the first proof-of-concept study for liposome-based photoelectrochemical (PEC) bioanalysis. Liposomes are microscopic spherical vesicles that possess a hollow cavity, and specific molecules/nanomaterials could be entrapped in their cavities or anchored onto their surfaces for targeted delivery of various species (e.g., genes, drugs, dyes, nutrients and cosmetics) or for versatile bioanalytical purposes via different detection modalities (e.g., fluorescent, electrochemical and colorimetric).1-9 Depending on their size and number of bilayers, liposomes can be classified to small unilamellar vesicles (SUVs), large unilamellar vesicles (LUVs), giant unilamellar vesicles (GUVs), oligolamellar vesicles (OLVs), and multilamellar vesicles (MLVs). In comparison with other types, SUVs have smaller size ( ＜ 100 nm) and one phospholipid bilayers. Besides, small unilamellar liposomes have relatively high stability, biocompatible, and nontoxic.5 For bioanalysis, the appeal of liposomes relies on the possibility of simple signaling via tracing the liposome-contained reporters, which is quite different from monitoring the enzymatic products in typical enzyme linked assays. Unfortunately, at this stage, their intriguing feature has never been disclosed in the field of newly emerged photoelectrochemical (PEC) bioanalysis, which is currently drawing extensive research interest due to its attractive advantages in terms of low cost, high sensitivity, easy operation and etc.10-20 For example, in the subfield of PEC protein detection, we recently proposed the use of Au nanoparticles (NPs) decorated TiO2 nanotubes for plasmonic immunoassay.21 Tang et al. then reported the use of Au nanocrystal decorated BiVO4 for novel semi-automated PEC immunoassay.22 Comparing with common enzyme- and nanomaterial-based labels in previous PEC bioanalysis, liposomes-based ones would offer well-established advantages as signaling reagents which include easy functionalization of the lipid bilayer with hydrophilic or hydrophobic biorecognition elements, high assay sensitivity stemming from the encapsulation of thousands of signaling molecules, instantaneous signals provided through surfactant-induced release of encapsulated contents, and the protective nature of the interior toward encapsulants conferring their increased long-term stability.23 Inspired by the high prosperity of liposomes, one question is naturally raised: whether the liposomes could be ingeniously implemented for innovative PEC bioanalysis? ACS Paragon Plus Environment

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With this motivation, we herein report the first liposomes-based PEC bioanalysis for the advanced PEC biomolecular detection.24-30 Using the immune-binding as the model recognition event, the proposed protocol eliminated the commonly needed laborious procedure on the photoelectrode surfaces (i.e., the semiconductor functionalization, probe immobilization, and the multiple incubation and washing steps associated with the molecular complexing), and thus reduced the bad influence against the photosensitive transducer for both benefits of facile operation and better performance.31-35 Specifically, the model system operated upon a sandwich immunoassay and the unilamellar liposomes containing enediol-ligands (ascorbic acid), which are unique moieties enabling the restoration of the undercoordinated surface Ti sites on TiO2 NPs.36-40 Our previous work of TiO2 NPs activation by in situ alkaline phosphatase (ALP) production of ascorbate has stimulated us to exploit the possibility of using liposomes to carry numerous enediol-ligands for achieving a highly sensitive PEC immunoassay.36 As shown in Scheme S1, the enediol-ligands-encapsulated liposomes (ELEL) were initially prepared by lipid film hydration method,4,6 followed by anchoring the antibodies onto the liposome surfaces via glutaraldehyde coupling method.9 On the other hand, as shown in Scheme 1, the 96-well plate was used for accommodating the sandwich immunocomplexing, and then the confined liposomes were directed to release the encapsulated enediol-ligands into individual well. Finally, the TiO2 NPs electrodes were subject to the in situ activation by the released enediol-ligands to transduce the recognition events. Since the formation of the ligand-to-metal charge transfer (CT) complex was intimately associated with the ELEL labels, a novel and interesting PEC immunoassay could be tailored which to our knowledge has not been published. Since various reporters could be carried by the liposomes,1,8 we believe this work will lay the foundation to the future prosperity of general liposomes-based PEC bioanalysis. Scheme 1. Enediol-Ligands-Encapsulated Liposomes for Novel PEC Immunoassay


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RESULTS AND DISCUSSION Experimentally, enediol-ligands were employed as the sensitizer reagent to be encapsulated into liposomes, and the corresponding ELEL was prepared by the lipid film hydration method (experimental details were included in the Supporting Information).6 The optimization of molar ratio of egg phosphatidylcholine/cholesterol used in the fabrication of ELEL was conducted with the results shown in Table S1. Then the as fabricated ELEL were characterized by transmission electron microscopy (TEM) and dynamic light scattering (DLS). The TEM image, as shown in Figure 1A, demonstrated that the size of the liposome is ∼40 ± 10 nm. Clearly, the ELEL maintained their quasi-spherical shape with the thin shell well-demarcated, and no rupture of the capsule wall was observed. This morphology strongly suggested that a typical vesicle structure had been formed. Additional size characterization based on a light scattering technique, as shown in Figure 1B, indicated that the liposomes had a narrow size distribution, with a diameter of approximately 60 nm. The DLS value was consistent with the TEM result, because the deposition of liposomes on the pure carbon film coated grids for the vacuum TEM imaging would cause the shrinkage of liposomes to some extent with a slight deformation. In addition, the stability of the liposomes can be evaluated by the zeta potential, since the uncharged or low charged liposomes tend to aggregate over time, while the negative or positive charged ones possess repulsive forces that against agglomeration.7 For present case, the zeta potential of the as-fabricated ELEL was


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measured to be -38.32 mV, while the values after storage of one week and one month were -38.36 mV and -38.70 mV, indicating the highly dispersibility and stability of the liposomal complex.8

A

100 Intensity / %

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50 nm

B

75 50 25 0

1

10

100 Size / nm

1000

Figure 1. (A) TEM image and (B) DLS of the as-prepared ELEL with uniform size.

UV-vis spectra were then measured for the bare liposome (curve a), enediol-ligands (curve b), and the as-fabricated ELEL (curve c) with the results shown in Figure 2A. As demonstrated, bare liposomes had no absorbance peak, whereas the enediol-ligands displayed its characteristic absorbance peak at ca. 243 nm. After encapsulating the enediol-ligands, the as-fabricated ELEL exhibited a similar absorbance peak, the appearance of which indicated the successful confinement of enediol-ligands inside the liposomes. Since the diameter of the liposomes was determined by the DLS as 60 nm, while the thickness of a lipid bilayers was assumed as 4 nm,6 the average volume of a single unilamellar liposome can thus be calculated as 1.13×10−13 µL. On the other hand, enediol-ligands encapsulation efficiency was further determined by high performance liquid chromatography (HPLC), as shown in Figure S1. The result showed that approximately 33% of the enediol-ligands were encapsulated in the liposomes, i.e., the total concentration of enediol-ligands in the liposome solution was determined to be 0.16 M. In this way, we can estimate that each liposome contained roughly 7.09×106 enediol-ligands molecules. It confirmed that enediol-ligands have been incorporated with high efficiency in this work. The high number of marker molecules that entrapped inside of per liposome would obviously be better for signal amplification.


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Photocurrent / µA

c 0.6 0.3 0.0 200

3

A

0.9 Absorption

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b

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B

c 2

on

1

off

b a

0 250 300 350 Wavelength / nm

400

0

5

10

15 20 Time / s

25

Figure 2. (A) UV−vis spectra of bare liposome (curve a), enediol-ligands (curve b), and the as-fabricated ELEL (curve c). (B) Photocurrent response of TiO2 NPs modified ITO electrode (curve a), after incubation of the lysis solution −1

corresponding to 0.01 mg mL

−1

(curve b) and 0.1 mg mL

antigen (curve c), respectively. The PEC tests were

performed in a 10 mM PBS solution (pH 7.4) with 0.0 V applied voltage and 410 nm excitation light.

After the confinement of the liposome complex by the sandwich immunorecognition, the captured liposomes were lysed by the addition of 1.0% (v/v) nonionic surfactant of Triton X-100 into the individual well. Then, the visible-light-responsibilities of the TiO2 NPs electrode before and after enediol-ligands chelation were then revealed by photocurrent action spectra. Figure 2B depicts the chronoamperometric I-t responses of bare TiO2 NPs electrode (curve a) and after activation corresponding to 0.01 mg mL−1 (curve b) and 0.1 mg mL−1 (curve c) antigen, respectively, upon visible light illumination. Obviously, upon irradiation, bare TiO2 NPs electrode hardly had any response due to its broad band gap excitation, while clear photocurrent signal was seen after in situ modification. With the increase of antigen concentration, enhanced photocurrent intensity was observed, indicated the analyte-controlled activation effect and also the feasibility of the proposed system. Incidentally, the SEM image and UV-vis diffuse reflectance spectra of TiO2 NPs electrode before and after surface enediolligands chelation have been recorded as in Figure S2 with the corresponding discussion. Scheme 2. Schematic Illustration of the Enediol-Ligands Chelation against Surface Ti Atom with the CT Processes upon Visible Light Irradiation and the Corresponding Energy-Level Diagram ACS Paragon Plus Environment

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The specific mechanism for this process was then illustrated in Scheme 2. As shown, the lysis of liposomes would release the enediol-ligands, which have a large affinity for the undercoordinated surface Ti atoms on TiO2 NPs since the monocyclic aromatic ligands possess the optimal geometry for surface chelating.38 Then the released enediol-ligands would experience in situ self-coordination onto the TiO2 NPs surface, i.e., the two OH groups would form an irreversible bidentate complex with the surface defect sites, building five-membered ring coordination and relaxing the surface Ti atoms to their intact anatase environment.40 This change of the coordination geometry would restore the surface defects and form an irreversible enediol-ligands-Ti charge transfer (CT) complex, as well as alter the energy-level positions with its absorption threshold shifting into the visible range.41 Specifically, after self-coordination, the localized orbital of surface-attached enediol-ligands would couple electronically with the delocalized electron levels from the CB band of TiO2 NPs, causing the formed CT complex significantly red shifting the TiO2 NPs absorption threshold (1.6 eV).36 When upon visible light excitation, the CT complex can thus induce electron transfer from the donating ligands directly into the empty conduction band (CB) of TiO2 NPs without transitioning through the excited state, generating the photocurrent for signaling.40


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Figure 3. (A) Derived calibration curve of the photocurrent enhancement vs target IgG concentration. (B) Selectivity of the proposed immunoassay to IgG by comparing it to the interfering proteins at the 500 ng mL−1 level: troponin I (cTnI), carcino embryonie antigen (CEA), p53, IgA and C-reactive protein (CRP). (∆I was the photocurrent enhancement corresponding to various IgG concentrations). Data were recorded in 10 mM PBS with 0.0 V applied potential and visible light irradiation.

Since the extent of signal increase associates intimately with the IgG concentration, a novel PEC immunoassay can be tailored by recording the photocurrent variation. Figure 3A displays the final photocurrent enhancement after immunorecognition with variable target concentrations. As expected, the signal increased as the target concentration increased, indicating the analyte-controlled release of the enediol-ligands and hence the enhanced sensitization effect for signal generation. The photocurrent increment was proportional to the logarithm of the Ag concentrations in a linear range from 0.1 pg mL−1 to 0.5 ng mL−1, and the detection limit was experimentally found to be 0.1 pg mL−1. Essentially, upon the increased immunobinding, more sandwich immunocomplexes could be induced and more enediolligands would be released for their functionalization; over 1.0 ng mL−1 the signal enhancement became placid which should be ascribed to the saturation of the self-coordination process on the TiO2 NPs electrode surface. The reproducibility of this PEC immunoassay was evaluated using an interassay relative standard deviation (RSD) through assaying the same 1.0 ng mL−1 samples with five electrodes, and RSD of 7.62% was obtained that reflected the acceptable reproducibility. As shown in Figure 3B, the selectivity of this work was assessed by using the protein troponin I (cTnI), carcino embryonie ACS Paragon Plus Environment

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antigen (CEA), p53, IgA and C-reactive protein (CRP) as interfering agents, and the results demonstrated that these species could not cause the signal increase and thus the satisfactory selectivity. As a proof-of-concept, these preliminary results proved the feasibility of the proposed liposomes-based PEC bioanalysis. The amplification effect may further be optimized by increasing the concentration of enediol-ligands incorporated into the liposomes and improving the sensitization efficiency by the superior TiO2 NPs electrodes. The standard fabrication of nanosized TiO2 NPs electrodes with smaller particle size and better uniformity is currently under the way. CONCLUSIONS In conclusion, we have descripted the first proof-of-concept study for liposome-based PEC bioanalysis. Using the enediol-ligands-encapsulated unilamellar liposomes, simple TiO2 NPs electrodes and the sandwich immunocomplexing upon the common 96-well plate, the model system was constructed and demonstrated an elaborate and extensible liposomes-based PEC bioanalysis protocol. The reasons why this original protocol is introduced and preferred to the traditional ones are 4-fold: (1) Sensitivity. Without the use of expensive and vulnerable enzymes for signal amplification, high sensitivity could be reached due to the release of numerous reporters from the liposome complexes; (2) Robustness. Such a protocol eliminated the bad effects of the laborious procedures against the photoelectrodes, the final one-step transduction of the recognition events would endow it with better applicability; (3) Simplicity. It exempted the commonly needed alignment between the complicated photoelectrodes and biorecognition events. Besides, other than the manipulation on the surfaces of separately fabricated photoelectrodes, the use of commercially available 96-well plate would further allow simultaneous processing of many samples with more facile operation; (4) Generality. This work possessed excellent extensibility, namely, with other judiciously coupled nanobiosystems composed of alternative recognition elements (such as antigen, and aptamer), specific reporters-encapsulated liposomes (eg., glucose, cysteine, DNA, etc.) and photoelectrodes (eg., TiO2 electrode，and CdS QDs electrode), this simple protocol could be easily adapted and serve as a general basis for addressing numerous other


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targets of interest or detecting dual targets using differential liposome labels. We thus believe it could offer a new perspective for the rational design and implementation of various functional liposome complexes for future PEC bioanalysis development. ASSOCIATED CONTENT Supporting Information The Supporting Information is available free of charge on the ACS Publications website at DOI: 10.1021/acs.analchem.xxxxxxx. Experimental section, synthesis of ELEL, the immunoassay development process, HPLC characterization of the ascorbic acid concentrations, SEM image and absorption spectra of TiO2 NPs electrode, and optimization of molar ratio of egg phosphatidylcholine/cholesterol. AUTHOR INFORMATION Corresponding Authors *E-mail: [email protected]; [email protected] *E-mail: [email protected] Notes The authors declare no competing financial interest. ACKNOWLEDGMENT Financial support from the National Natural Science Foundation of China (Grant Nos. 21327902, 21305063 and 21675080), and the Natural Science Funds of Jiangsu Province (Grant BK20130553) is appreciated. This work was also supported by a Project Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions.


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REFERENCES (1) Bui, M.-P. N.; Ahmed, S.; Abbas, A. Nano Lett. 2015, 15, 6239. (2) Lozano, N.; Al-Jamal, W. T.; Taruttis, A.; Beziere, N.; Burton, N. C.; Van den Bossche, J.; Mazza, M.; Herzog, E.; Ntziachristos, V.; Kostarelos, K. J. Am. Chem. Soc. 2012, 134, 13256. (3) Qian, R.-C.; Cao, Y.; Long, Y.-T. Angew. Chem. 2016, 128, 729. (4) Ou, L.-J.; Liu, S.-J.; Chu, X.; Shen, G.-L.; Yu, R.-Q. Anal. Chem. 2009, 81, 9664. (5) Edwards, K. A.; Baeumner, A. J. Anal. Chem. 2014, 86, 6610. (6) Lin, B.-Q.; Liu, D.; Yan, J.-M.; Qiao, Z.; Zhong, Y.-X.; Yan, J.-W.; Zhu, Z.; Ji, T.-H.; Yang, C.-Y. J. ACS Appl. Mat. Interfaces. 2016, 8, 6890. (7) Pattni, B. S.; Chupin, V. V.; Torchilin, V. P. Chem. Rev. 2015, 115, 10938. (8) Zhou, J.; Wang, Q.-X.; Zhang, C.-Y. J. Am. Chem. Soc. 2013, 135, 2056. (9) Chen, H.; Zheng, Y.; Jiang, J.-H.; Wu, H.-L.; Shen, G.-L.; Yu, R.-Q. Biosens. Bioelectron. 2008, 24, 684. (10) Zhao, W.-W.; Xu, J.-J.; Chen, H.-Y. Chem. Rev. 2014, 114, 7421. (11) Zhao, W.-W.; Xu, J.-J.; Chen, H.-Y. Chem. Soc. Rev. 2015, 44, 729. (12) Tang, J.; Zhang, Y.-Y.; Kong, B.; Wang, Y.-C.; Da, P.-M.; Li, J.; Elzatahry, A. A.; Zhao, D.-Y.; Gong, X.-G.; Zheng, G.-F. Nano Lett. 2014, 14, 2702. (13) Zhang, X.-R.; Liu, M.-S.; Liu, H.-X.; Zhang, S.-S. Biosens. Bioelectron. 2014, 56, 307. (14) Li, H.-N.; Mu, Y.-W.; Yan, J.-R.; Cui, D.-M.; Ou, W.-J.; Wan, Y.-K.; Liu, S.-Q. Anal. Chem. 2015, 87, 2007. (15) Chen, D.; Zhang, H.; Li, X.; Li, J.-H. Anal. Chem. 2010, 82, 2253. (16) Zhang, N.; Ma, Z.-Y.; Ruan, Y.-F.; Zhao, W.-W.; Xu, J.-J.; Chen, H.-Y. Anal. Chem. 2016, 88, 1990. (17) Zhao, W.-W.; Xu, J.-J.; Chen, H.-Y. TrAC, Trends Anal. Chem. 2016, 82, 307. (18) Zhao, W.-W.; Yu, P.-P.; Shan, Y.; Wang, J.; Xu, J.-J.; Chen, H.-Y. Anal. Chem. 2012, 84, 5892.


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(19) Zhao, W.-W.; Yu, X.-D.; Xu, J.-J.; Chen, H.-Y. Nanoscale. 2016, 8, 17407. (20) Zhao, W.-W.; Xu, J.-J.; Chen, H.-Y. Analyst. 2016, 141, 4262. (21) Zhu, Y.-C.; Zhang, N.; Ruan, Y.-F.; Zhao, W.-W.; Xu, J.-J.; Chen, H.-Y. Anal. Chem. 2016, 88, 5626. (22) Shu, J.; Qiu, Z.-L.; Lin, Z.-Z.; Cai, G.-N.; Yang, H.-H.; Tang, D.-P. Anal. Chem. 2016, 88, 12539. (23) Campardelli, R.; Trucillo, P.; Reverchon, E. Ind. Eng. Chem. Res. 2016, 55, 5359. (24) Zhou, H.; Liu, J.; Zhang, S.-S. TrAC, Trends Anal. Chem. 2015, 67, 56. (25) Tang, J.; Li, J.; Da, P.-M.; Wang, Y.-C.; Zheng, G.-F. Chem.–Eur. J. 2015, 21, 11288. (26) Zhang, N.; Zhang, L.; Ruan, Y.-F.; Zhao, W.-W.; Xu, J.-J.; Chen, H.-Y. Biosens. Bioelectron. 2017, 94, 207. (27) Tang, J.; Kong, B.; Wang, Y.-C.; Xu, M.; Wang, Y.-L.; Wu, H.; Zheng, G.-F. Nano Lett. 2013, 13, 5350. (28) Wang, G.-L.; Shu, J.-X.; Dong, Y.-M.; Wu, X.-M.; Zhao, W.-W.; Xu, J.-J.; Chen, H.-Y. Anal. Chem. 2015, 87, 2892. (29) Tu, W.-W.; Dong, Y.-T.; Lei, J.-P.; Ju, H.-X. Anal. Chem. 2010, 82, 8711. (30) Zhao, W.-W.; Xu, J.-J.; Chen, H.-Y. Biosens. Bioelectron. 2017, 92, 294. (31) Wang, L.-N.; Ma, W.-G.; Gan, S.-Y.; Han, D.-X.; Zhang, Q.-X.; Niu, L. Anal. Chem. 2014, 86, 10171. (32) Haddour, N.; Chauvin, J.; Gondran, C.; Cosnier, S. J. Am. Chem. Soc. 2006, 128, 9693. (33) Zhuang, J.-Y.; Lai, W.-Q.; Xu, M.-D.; Zhou, Q.; Tang, D.-P. ACS Appl. Mat. Interfaces. 2015, 7, 8330. (34) Zhao, K.; Yan, X.-Q.; Gu, Y.-S.; Kang, Z.; Bai, Z.-M.; Cao, S.-Y.; Liu, Y.-C.; Zhang, X.-H.; Zhang, Y. Small. 2016, 12, 245. (35) Li, X.; Zhu, L.-S.; Zhou, Y.-L.; Yin, H.-S.; Ai, S.-Y. Anal. Chem. 2017, 89, 2369. (36) Zhao, W.-W.; Ma, Z.-Y.; Xu, J.-J.; Chen, H.-Y. Anal. Chem. 2013, 85, 8503.


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(37) Tae, E. L.; Lee, S. H.; Lee, J. K.; Yoo, S. S.; Kang, E. J.; Yoon, K. B. J. Phys. Chem. B. 2005, 109, 22513. (38) Garza, L. d. l.; Saponjic, Z. V.; Dimitrijevic, N. M.; Thurnauer, M. C.; Rajh, T. J. Phys. Chem. B. 2006, 110, 680. (39) Dimitrijevic, N. M.; Saponjic, Z. V.; Rabatic, B. M.; Rajh, T. J. Am. Chem. Soc. 2005, 127, 1344. (40) Ma, W.-G.; Wang, L.-N.; Zhang, N.; Han, D.-X.; Dong, X.-D.; Niu, L. Anal. Chem. 2015, 87, 4844. (41) Rajh, T.; Nedeljkovic, J. M.; Chen, L. X.; Poluektov, O.; Thurnauer, M. C. J. Phys. Chem. B. 1999, 103, 3515.

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Enediol-Ligands-Encapsulated Liposomes Enables Sensitive

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