Renewable Starch Carriers with Switchable Adsorption Properties

Mar 6, 2018 - Modified Phase Change Microcapsules with Calcium Carbonate and Graphene Oxide Shells for Enhanced Energy Storage and Leakage Prevention...
0 downloads 13 Views 2MB Size
Subscriber access provided by UNIV OF SCIENCES PHILADELPHIA

Renewable Starch Carriers with Switchable Adsorption Properties Abdalla H. Karoyo, Leila Dehabadi, and Lee D. Wilson ACS Sustainable Chem. Eng., Just Accepted Manuscript • DOI: 10.1021/ acssuschemeng.7b03345 • Publication Date (Web): 06 Mar 2018 Downloaded from http://pubs.acs.org on March 7, 2018

Just Accepted “Just Accepted” manuscripts have been peer-reviewed and accepted for publication. They are posted online prior to technical editing, formatting for publication and author proofing. The American Chemical Society provides “Just Accepted” as a service to the research community to expedite the dissemination of scientific material as soon as possible after acceptance. “Just Accepted” manuscripts appear in full in PDF format accompanied by an HTML abstract. “Just Accepted” manuscripts have been fully peer reviewed, but should not be considered the official version of record. They are citable by the Digital Object Identifier (DOI®). “Just Accepted” is an optional service offered to authors. Therefore, the “Just Accepted” Web site may not include all articles that will be published in the journal. After a manuscript is technically edited and formatted, it will be removed from the “Just Accepted” Web site and published as an ASAP article. Note that technical editing may introduce minor changes to the manuscript text and/or graphics which could affect content, and all legal disclaimers and ethical guidelines that apply to the journal pertain. ACS cannot be held responsible for errors or consequences arising from the use of information contained in these “Just Accepted” manuscripts.

is published by the American Chemical Society. 1155 Sixteenth Street N.W., Washington, DC 20036 Published by American Chemical Society. Copyright © American Chemical Society. However, no copyright claim is made to original U.S. Government works, or works produced by employees of any Commonwealth realm Crown government in the course of their duties.

Page 1 of 34 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

ACS Sustainable Chemistry & Engineering

1

Renewable Starch Carriers with Switchable Adsorption Properties

Abdalla H. Karoyo1, Leila Dehabadi1, and Lee D. Wilson.1* 1

Department of Chemistry, University of Saskatchewan, 110 Science Place, Saskatoon, SK. CANADA S7N 5C9

*Corresponding

Author: L. D. Wilson, Email: [email protected] Tel. +1-306-966-2961, Fax. +1-306-966-4730

ACS Paragon Plus Environment

ACS Sustainable Chemistry & Engineering 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

2

ABSTRACT This report describes a systematic study on the structure and sorption properties of carnation-based starch-particles (SPs) by various techniques. Structural characterization of the SPs utilized spectroscopy (1H-NMR and FT-IR), scanning electron microscopy (SEM), differential scanning calorimetry (DSC), and thermogravimetric analysis (TGA). The sorption properties of the SPs were characterized by solvent swelling and uptake isotherms with cationic adsorbates at equilibrium and kinetic conditions. The surface area (SA; ~3 m2/g – 588 m2/g) of the SPs was estimated using nitrogen gas and dye adsorption isotherm methods, where the range in SA was related to solvent swelling effects on the textural properties. The SPs contain lipid constituents according to results obtained by 1H-NMR spectroscopy, DSC, and confocal laser microscopy (CLM) with iodine staining. The unique solvent swelling properties of the SPs reveal greater swelling in water over ethanol. SPs display preferential equilibrium uptake of methylene blue (MB; Qm ~ 716 mg/g) over cetylpyridinium bromide (CPB; Qm ~ 292 mg/g). The uptake of MB was reduced by an order of magnitude (Qm ~ 67 mg/g) when the SPs were doped with CPB, further revealing the role of competitive adsorption and similar binding modes for MB and CPB. The doping of SPs with CPB provide a facile approach for alteration of the surface functional properties such as the hydrophile-lipophile character, surface charge, and hydration properties of the SPs. Evidence of monolayer and multilayer adsorption of CPB onto SPs lead to switchable adsorption properties where such amphiphile surface patterning can be harnessed to yield materials with unique controlled-release properties for diverse chemical systems according to tunable surface charge using self-assembly. Key words: quaternary structure; starch particles; adsorption; swelling; cationic surfactant; selfassembly

ACS Paragon Plus Environment

Page 2 of 34

Page 3 of 34 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

ACS Sustainable Chemistry & Engineering

3

Introduction Amylose (AM) and amylopectin (AP) are the two key biopolymers that influence the composition of many plant-based starch granules. Due to the unique physicochemical properties of AM and AP, starch materials have widespread applications in food processing and in industry as thickeners, gelling agents and desiccants.1,2 The hydrophilicity of starch relates to the presence of its abundant hydroxyl (-OH) groups.3 The unique solution chemistry of starch materials contribute to the ability of starch to form gel networks at very low concentration, where the morphology of such systems affect their chemical stability and mechanical properties.4 Carnationbased starch-particles (SPs) as reported herein possess unique properties according to a low amylose content (Table 1), large surface area (SA), uniform particle size (ca. 2 µm), and large pore volume. The higher amylopectin content of SPs lend to diverse applications (e.g. food and cosmetics industry) that differ from conventional starches (e.g. maize, potato and waxy starch). As well, SPs may also contain lipids and proteins (< 6%)5 and various minerals (~ 0.4 %; e.g. calcium and magnesium)6 that contribute to the overall quaternary structure and the textural properties. Lipid constituents in starches are known to exist in a free-state (unbound) or bound by formation of noncovalent/covalent interactions with starch.7-9 In the case of noncovalent binding, lipids can become encapsulated by starch due to the ability of amylose to form helicoid inclusion complexes.10 The presence of lipids in the structure of the SPs may impart amphiphilic character by enhancing the binding affinity with polar and apolar guest molecules. Continued interest in the use of starch-based materials generally relate to their low-cost, non-toxicity, biocompatibility, biodegradability and sustainable nature. It is worthy to mention that the adsorption-desorption properties of macromolecules play a key role in the fate and transport properties of their complexes with guest species, as evidenced by various adsorbents: activated carbon,11 clay minerals,12–14 cross-linked amphoteric starch,15 weed biomass,16 fly ash,17,18 Indian rosewood sawdust,19 and cross-linked chitosan beads.20 Similar to the host-guest behavior of polysaccharides such as cyclodextrins (CDs),21 the phase behavior of SPs as carriers influence the fate and transport of additives in their bound and dispersed states, respectively. In contrast to CDs, SPs offer a low cost alternative as carrier systems for agrochemicals, pharmaceuticals, cosmetics, food, and as scaffolds for tissue regeneration.22 SPs are potential adsorbents and carriers for diverse guest species according to the variable adsorption-desorption properties with model dye systems.23 The textural and surface properties of SPs enhance their wettability,24 conformational

ACS Paragon Plus Environment

ACS Sustainable Chemistry & Engineering 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

4

flexibility, and ability to form host-guest complexes.25 Despite wide reports on the tunable uptakerelease properties of engineered polysaccharide materials with target compounds, the structurefunction (adsorption) relationship of starch-based granules are sparsely reported. This area warrants further attention due to the unique morphology, textural, and surface chemical properties of starch-based materials. We report on a systematic structural and physicochemical characterization study of SPs as carrier systems with model compounds relevant to a wide range of adsorption-based processes. The textural and surface chemical properties were studied by complementary methods; NMR and FT-IR spectroscopy, DSC, TGA, and SEM. The uptake properties of the SPs were evaluated using isotherm studies and microscopy with model cationic compounds such as methylene blue (MB), cetylpyridinium bromide (CPB), CPB-MB binary mixtures, and anionic dyes (phenolphthalein and iodine). The uptake properties of SPs are anticipated to provide unique structural and thermodynamic insight on the modes of adsorbent-adsorbate interactions. As well, the co-addition of a surfactant (e.g. CPB) to ligands (e.g. MB) is known to alter the optical properties of the ligand to provide rapid and reliable spectrophotometric methods for improved sensitivity and selectivity of detection.26 CPB is also an important antibacterial agent that has been immobilized and formulated with polysaccharide-based excipients.27,28 The present study highlights several key contributions: i) new insight on the structure-function (adsorption) properties of SPs as adsorbents through the use of structural and isotherm studies, and ii) the utility of surfactant self-assembly to alter the HLB character and the sorption properties of SPs. The results of this study will catalyze further research on the rational design of sustainable biopolymer carriers for diverse scientific and technological applications. In the case of SPs, the immobilization of amphiphilic substituents is anticipated to yield variable catalytic efficiency,29 controlled-release functionality,30 and molecular recognition due to the role of surface patterning and gating effects in sorption-based processes.

Experimental and methods Materials and Chemicals Starch particles (SPs) that contain variable amylose (AM; 13%) and amylopectin (AP; 87%) were obtained locally from the seed of Prairie Carnation plant species. The SPs were extracted by mechanical milling along with alkaline and aqueous extraction (Carnation BioProducts Inc.,

ACS Paragon Plus Environment

Page 4 of 34

Page 5 of 34 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

ACS Sustainable Chemistry & Engineering

5

Saskatoon, SK). Selected properties for the Carnation SPs are listed in Table 1. Methylene blue (MB), cetylpyridinium bromide (CPB), phenolphthalein (Phth), and iodine were purchased from Alfa Aesar, Canada. Dimethyl sulfoxide-d6 (DMSO-d6) and all other organic solvents were purchased from Sigma Aldrich. Millipore water was used for the preparation of all aqueous solutions unless specified otherwise. Table 1. Properties of Carnation Starch Particles (SPs)a Amylose

Amylopectin

pH in water

Mean granule

Solubility at

Gelatinization

content (%)

content (%)

at 25 °C

size (µm)

70 °C (g/L)

(° C)

87

7.0-8.0

13 a

0.8 mM (Fig. 9b, inset), in accordance with the general features of a BET isotherm model when Ce > CMC. Multilayer adsorption of CPB onto SPs is supported by another report on the self-assembly of n-alkyl carboxylates onto cross-linked amylose described elsewhere.69 Based on the ongoing discussion, the respective interactions for adsorption of MB and CPB onto SPs is illustrated in Scheme 1. The formation of hemi-micelles or multilayer aggregates (Scheme 1c) is thermodynamically favored for CPB at levels near or above the CMC (Table 2).

In the case of co-adsorption of MB+CPB (Scheme 1 b) with SPs, competition for binding sites at the adsorbent surface increases, especially when CPB undergoes adsorption before addition of MB, resulting in fewer adsorption sites, as evidenced by attenuated adsorption of MB observed in the case of a mixed (MB+CPB) system. An approximate 10-fold lower uptake of MB (Qm = 0.21 mmol/g) occurs in the mixed system versus the single component MB system (Qm = 2.24 mmol/g), in the absence of CPB. The competitive binding between MB and CPB indicate that

ACS Paragon Plus Environment

ACS Sustainable Chemistry & Engineering 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 22 of 34

22

cation-dipole interactions play a key role for these structurally dissimilar cations. The delocalized charge of MB and the potential of cation/-OH interactions with SPs may stabilize the surface binding interactions (Scheme 1 a).

Scheme 1. Depiction of mode of adsorption for as-received starch particles (SPs) with (a) MB monolayer, (b) MB + CPB monolayer, and (c) CPB with multilayer adsorption.

Table 2. Best fit Sips isotherm parameters for the uptake of MB and CPB at 295K with SPs. Sorbates

Molecular

Molar Mass

Water

Qm

Ks

Formula

(g/mol)

Solubility

(mmol/g)

(L/g)

ns

CMC

Log

pKa

(mM)

Kow

(g/L) 20 °C

MB

C16H18ClN3S

319.85

40

2.24

0.78

1.3

3.8

0.30 – 0.06a 70

5.85

CPB

C21H38BrN

384.45

5

0.76

1.85

0.4

4.3

0.4571

1.83

CPB+MB

n/a

n/a

n/a

0.21

0.93

1.7

n/a

0.9b

n/a

This study a

Note: MB does not form micelles but can form dimer species according to previous reports with a corresponding dimerization constant (KD = 1.710-4)72 b Estimated graphically based on the rise in uptake relative to the monolayer uptake plateau in Fig. 9 (see inset)

Kinetic uptake studies for MB were carried out that parallel those described by the equilibrium results in Figure 9 (Fig. S2a-b and Table S1, SI). It should be noted that the concentration levels of either MB or CPB are at the M level, in contrast to mM levels used for the equilibrium study above for the cation species. In brief, the kinetic uptake of MB exceeds that for CPB in single component SPs/cation systems (Scheme 1a), along with the uptake for simultaneous co-adsorption of MB in binary (CPB+MB) solutions (Scheme 1b). In the case where CPB is pre-adsorbed prior to addition of MB, the kinetics of adsorption are retarded, in agreement with the equilibrium results in Fig. 9 since CPB occupies the same binding sites as MB due to the

ACS Paragon Plus Environment

Page 23 of 34 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

ACS Sustainable Chemistry & Engineering

23

key role of cation-starch interactions. The highest kinetic uptake is shown for high amylose starch (HAS) with MB compared to the SPs/MB system and may relate to the greater amylose content of this starch granule and the greater accessibility of the adsorption sites relative to SPs. The greater AP content of SPs may present steric effects due to extensive starch branching that account for the differences in kinetic uptake. The pre-adsorption of CPB followed by kinetic uptake of MB shows parallel trends related to attenuated uptake, as evidenced in Fig. 9. Steric effects due to the C16alkyl chain of CPB lower the kinetic uptake of MB in the pre-adsorbed binary system and to a lesser extent for co-adsorption. The kinetic profiles are well described on the basis of the pseudofirst order (PFO) model, while the time required to reach pseudo-equilibrium beyond 4 h reveals the role of intraparticle diffusion effects for the rate determining step in the kinetic process. These kinetic results further highlight the role of the unique architecture of alternating crystalline and amorphous lamellae units of SPs. In general, the unique architecture due to the alternating crystalline and amorphous lamellae domains of starch influence the surface/textural and morphological properties of the SPs. The unique structure and superior adsorption properties for the as-received SPs are compared with other adsorbent materials from the literature (Table 3). The notable MB uptake by SPs versus other biomaterials provide compelling evidence of the unique textural properties and morphology of the SPs in aqueous media. The high equilibrium uptake of MB by SPs may relate to an orthogonal binding orientation of MB with the surface of SPs versus a coplanar binding mode. The welldefined monolayer adsorption capacity of SPs do not appear to be affected by secondary contributions due to π-π stacking of MB due to dimer formation.72

ACS Paragon Plus Environment

ACS Sustainable Chemistry & Engineering 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 24 of 34

24

Table 3. Selected studies of uptake of MB for various materials.73-77, 58 Adsorbents

Qm

SA

(mg/g)

(m2/g)

pH

Refs

Garlic Peel

82.6

0.561c

4-12

73

Rice husk

40.5

20.1c

3-8

73

Raw beech sawdust

9.8

4.91c

1.5-13

75

5

76

Oil palm trunk fiber

150

64.44 3.00

Cross-linked porous starch

9.5

Coconut leaf activated carbon Starch

250

microspheres

67.2*

(as-received)

c

10.5 77

716.2#

632 c

5.6

2.89 c

6

55.1d* 588.1

d#

58

Present Study

c

SA estimated using nitrogen adsorption result SA estimated using adsorption of methylene blue as reported by Guo & Wilson [see eq. (3) in ref. 79] *MB with CPB, #Pure MB (without CPB). d

Conclusions In summary, Carnation-based starch particles (SPs) were structurally characterized using complementary spectral (FT-IR, NMR), confocal microscopy, SEM, and thermal (DSC, TGA) methods. The amylopectin rich SPs are ca. 2 m in diameter and contain relatively low levels of lipids that are strongly bound within the SPs architecture, according to NMR spectroscopy. The SPs display unique solvent swelling in polar solvents and selective solvent uptake of water over ethanol in neat solvents. SPs have demonstrably favorable swelling in water and adsorption of cation species, as compared with maize-, corn- and soluble-starch materials with greater AP content. The role of textural properties and HLB character of SPs relate to the unique lamellae domains that are partially revealed by SEM and gas adsorption results. In aqueous solution, the role of SPs architecture and hydration phenomena is shown by adsorption studies using anion dyes (iodine and phenolphthalein) and two cation adsorbates (MB and CPB).

ACS Paragon Plus Environment

Page 25 of 34 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

ACS Sustainable Chemistry & Engineering

25

The adsorption results at kinetic (Fig. S2, SI) and equilibrium (Fig. 9) conditions reveal that the uptake of MB and CPB are driven by ion-dipole interactions between the cation with starch at the Lewis base surface sites (-OH) of the SPs (Scheme 1), in accordance with the negative zetapotential of the starch surface (Fig. S1, SI). The variable -OH site accessibility of different starch materials are supported by the Phth decolorization and CLSM iodine staining results, in agreement with the variable AP/AM composition of starch. In the case of CPB-doped SPs, fewer active sites are available for MB to adsorb according to a Langmuir lattice model, in agreement with observed steric effects in binary (CPB+MB) systems and the key role of cation-starch interactions. SPs differ markedly to other amylose-rich SPs based on the unique morphology and surface accessible binding sites. Adsorption of MB and CPB by SPs at equilibrium and kinetic conditions are driven by cation-dipole interactions. The secondary role of hydrophobic effects for CPB is supported by the tendency to undergo multilayer adsorption at higher concentration (Scheme 1c). This study highlights a facile approach involving self-assembly of monolayers and multilayers onto SPs and the potential role of noncovalent surface modification to yield switchable adsorption properties (Scheme 1). Carnation-based SPs display promising potential as novel sustainable carriers in food processing, environmental remediation, and chemical separations. The results presented herein will catalyze the development of switchable controlled-release carriers for tailored applications of supramolecular constructs with possible molecular gating effects toward charged species during adsorption-desorption events78,79 in response to external stimuli.

Acknowledgements The authors are grateful to the University of Saskatchewan and the support provided by the Government of Saskatchewan (Ministry of Agriculture) through the Agriculture Development Fund (Project#: 20160266) for this research and for the provision of a complimentary research sample of starch particles by Michael Oelck at Carnation BioProducts Inc. (Saskatoon, SK.).

Associated content Supporting Information

ACS Paragon Plus Environment

ACS Sustainable Chemistry & Engineering 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

26

Detailed experimental procedures, zeta-potential and kinetic adsorption profiles with accompanying kinetic parameters are provided. This material is available free of charge via the Internet at http://pubs.acs.org.

AUTHOR INFORMATION *Corresponding Author: L. D. Wilson, E-mail: [email protected]

Notes The authors declare no competing financial interests.

References 1. Che, P.; Lall, S.; Howell, S. H. Developmental steps in acquiring competence for shoot development in Arabidopsis tissue culture. Planta, 2007, 226, 1183–1194. http://dx.doi.org/10.1007/s00425-007-0565-4

2. Tester, R. F.; Karkalas, J.; Qi, X. Starch structure and digestibility Enzyme-Substrate relationship. Worlds Poult. Sci. J. 2004, 60 (2), 186-195. DOI: 10.1079/WPS200312

3. Alcazar-Alay, S. C.; Meireles, M. A. A. Physicochemical properties, modifications and applications of starches from different botanical sources, Food Sci. Technol, Campinas, 2015, 35(2), 215-236. http://dx.doi.org/10.1590/1678-457X.6749

4. Karoyo, A. H.; Wilson, L. D. Physicochemical Properties and the Gelation Process of Supramolecular Hydrogels: A Review, Gels, 2017, 3, 1-18. doi:10.3390/gels3010001

5. Hu, P.; Xiaoxu, F.; Lingshang, L.; Juan, W.; Long, Z.; Cunxu, W. Effects of surface proteins and lipids on molecular structure, thermal properties, and enzymatic hydrolysis of rice starch. Food Sci. Technol.Campinas, 2017, DOI: 10.1590/1678-457X.35016.

6. Appelqvist, I. A. M.; Debet, M. R. M. Starch-biopolymer interactions: a review. Food Rev. Int. 1997, 13, 163-224. https://doi.org/10.1080/87559129709541105

7. William, R. M. Lipids in Cereal Starches: A Review, J. Cereal Sci. 1988, 8(1), 1-15. https://doi.org/10.1016/S0733-5210(88)80044-4

8. Morrison, W. R. Starch lipids and how they relate to starch granule structure and functionality. Cereal Foods World, 1995, 40, 437-446.

ACS Paragon Plus Environment

Page 26 of 34

Page 27 of 34 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

ACS Sustainable Chemistry & Engineering

27

9. Vasanthan, T.; Hoover, R. Comparative study of the com-position of lipids associated with starch granules from various botanical sources. Food Chem. 1992, 43, 19-29. https://doi.org/10.1016/03088146(92)90236-U

10. Putseys, J. A.; Derde, L. J.; Lamberts, L.; Ostman, E.; Björck, I. M.; Delcour, J. A. Functionality of short chain amylose-lipid complexes in starch-water systems and their impact on in vitro starch degradation. J. Agric. Food Chem. 2010, 58(3), 1939-45. doi: 10.1021/jf903523h.

11. Ghaedi, M.; Golestani Nasab, S.; Khodadoust, M. R. Azizian, S. Application of activated carbon as adsorbents for efficient removal of methylene blue: Kinetics and equilibrium study, Ind. Eng. Chem. Res. 2014, 20 (4), 2317-2324. https://doi.org/10.1016/j.jiec.2013.10.007

12. Carraro, A.; De Giacomo, A.; Giannossi, M. L.; Medici, L.; Muscarella, M.; Palazzo, L.; Quaranta, V.; Summa, V.; Tateo, F. Clay minerals as adsorbents of aflatoxin M1 from contaminated milk and effects on milk quality, Appl. Clay Sci. 2014, 88–89, 92–99. https://doi.org/10.1016/j.clay.2013.11.028

13. Macewan, D. M. C. Clay minerals as catalysts and adsorbents. Nature. 1948. 31, 161-198. doi:10.1038/162195a0

14. Uddin, M. K. A review on the adsorption of heavy metals by clay minerals, with special focus on the past decade. Chem. Eng. J. 2017, 308, 438–462. https://doi.org/10.1016/j.cej.2016.09.029

15. Haroon, M.; Wang, L.; Yu, H.; Abbasi, N. M.; Zain-ul-Abdin, M. S.; Khan, R. U.; Ullah, R. S.; Chen, Q.; Wu, J. Chemical modification of starch and its application as an adsorbent material. RSC Adv. 2016, 6, 78264–78285. DOI: 10.1039/C6RA16795K

16. Dixit, A.; Dixit, S.; Goswami, C. S. Eco-friendly Alternatives for the Removal of Heavy Metal Using Dry Biomass of Weeds and Study the Mechanism Involved. J. Bioremed Biodeg. 2015, 6 (3), 1-7. DOI: 10.4172/2155-6199.1000290

17. Ahmaruzzaman, M. Role of Fly Ash in the Removal of Organic Pollutants from Wastewater. Energy Fuels, 2009, 23, 1494–1511. DOI: 10.1021/ef8002697

18. Wang, S.; Wu, H. Environmental-benign utilization of fly ash as low-cost adsorbents, J. Hazardous Mater. 2006, 136 (3), 482-501. https://doi.org/10.1016/j.jhazmat.2006.01.067

19. Adegoke, K. A.; Bello, O. S. Dye sequestration using agricultural wastes as adsorbents. Water Resour. Ind. 2015, 12, 8–24. https://doi.org/10.1016/j.wri.2015.09.002

20. Gyananath, G.; Balhal, D. K. Removal of lead (II) from aqueous solutions by adsorption onto chitosan beads. Cellulose Chem. Technol. 2012, 46 (1-2), 121-124.

21. Malafaya, P. B.; Stappers, F.; Reis, R. L. Starch-based microspheres produced by emulsion crosslinking with a potential media dependent responsive behavior to be used as drug delivery carriers. J. Mater Sci. Mater Med. 2006, 17(4), 371-7. DOI:10.1007/s10856-006-8240-z

ACS Paragon Plus Environment

ACS Sustainable Chemistry & Engineering 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 28 of 34

28

22. Vedha Hari, B. N.; Praneetha, T.; Prathyusha, T.; Mounika, K.; Devi, D. R. Development of starchgelatin complex microspheres as sustained release delivery system. J. Adv. Pharm. Technol. Res. 2012, 3(3), 182–187. doi: 10.4103/2231-4040.101015

23. Huo, X. P.; Wang, F.; Deng, D.; Wang, L. Adsorption of Methylene Blue on Starch Microsphere from Aqueous Solutions. Adv. Mat. Res. 2012, 557, 1109-1112.

24. Wiacek, A. E.; Dul, K. Effect of Surface Modification on Starch-Phospholipid Wettability. Colloids and

Surfaces

A:

Physicochem.

Eng.

Aspects.

2015,

480,

351-359.

https://doi.org/10.1016/j.colsurfa.2015.01.085

25. Yang, Y.; Wei, X.; Sun, P.; Wan, J. Preparation, Characterization and Adsorption Performance of a Novel

Anionic

Starch

Microsphere.

Molecules,

2010,

15,

2872-2885.

doi:

10.3390/molecules15042872.

26. Benamor, M.; Aguersif, N.; Draa, M.T. Spectrophotometric determination of cetylpyridinium chloride in

pharmaceutical

products.

J.

Pharm.

Biomed.

Anal.

2001,

26(1),

151-154.

https://doi.org/10.1016/S0731-7085(01)00348-X

27. Cutter, C. N.; Dorsa, W. J.; Handie, A.; Rodriguez-Morales, S.; Zhou, X.; Breen, P. J.; Compadre, C. M. Antimicrobial activity of cetylpyridinium chloride washes against pathogenic bacteria on beef surfaces. J. Food Prot. 2000, 63(5), 593-600.

28. Malek, N. A.; Ramli, N. I. Characterization and antibacterial activity of cetylpyridinium bromide (CPB) immobilized on kaolinite with different CPB loadings.

Applied Clay Sci. 2015, 109, 8-14.

https://doi.org/10.1016/j.clay.2015.03.007

29. Qi, W.; Wang, Y.; Li, W.; Wu, L. Surfactant-Encapsulated Polyoxometalates as Immobilized Supramolecular Catalysts for Highly Effective and Selective Oxidation Reactions. Chem. Eur. J. 2010, 16, 1068-1078. DOI: 10.1002/chem.200902261

30. Friedman, R. B. Controlled release agent for cetylpyridinium chloride. US. Patent 4774329, August 4, 1987.

31. Dehabadi, L.; Wilson, L. D. Polysaccharide-based materials and their adsorption properties in aqueous solution. Carbohydr. Polym. 2014, 113, 471–479. https://doi.org/10.1016/j.carbpol.2014.06.083

32. Udoetok, I. A.; Dimmick, R. M. Wilson, L. D. Headley. J. V. Adsorption properties of cross-linked cellulose-epichlorohydrin polymers in aqueous solution. Carbohydr. Polym. 2016, 136, 329–340. https://doi.org/10.1016/j.carbpol.2015.09.032

33. Mohamed, M. H.; Wilson, L. D.; Headley, J. V.; Peru, K. M. Thermodynamic Properties of Inclusion Complexes between β-Cyclodextrin and Naphthenic Acid Fraction Components. Energy Fuels, 2015, 29, 3591−3600. DOI: 10.1021/acs.energyfuels.5b00289

ACS Paragon Plus Environment

Page 29 of 34 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

ACS Sustainable Chemistry & Engineering

29

34. Wilson, L.D.; Mohamed, M. H.; Berhaut, C. L. Sorption of Aromatic Compounds with Copolymer Sorbent

Materials

Containing

β-Cyclodextrin.

Materials,

2011,

4,

1528-1542.

doi:

10.3390/ma4091528.

35. Pratt, D. Y.; Wilson, L. D.; Kozinski, J. A.; Morhart, A. M. Preparation and sorption studies of βcyclodextrin/epichlorohydrin copolymers. J. Appl. Polym. Sci. 2010, 116(5), 2982–2989. DOI 10.1002/app.31824

36. Sips, R. On the Structure of a Catalyst Surface. J. Phys. Chem. 1948, 16, 490-495. https://doi.org/10.1063/1.1746922

37. Foo, K.Y.; Hameed B. H. Insights into the modeling of adsorption isotherm systems. Chem. Eng. J. 2010, 156, 2-10. https://doi.org/10.1016/j.cej.2009.09.013

38. Krssak, M.; Peterson, K. F.; Dresner, A.; DiPrietro, L.; Vogel, S. M.; Rothman, D. L.; Shulman, G. I.; Roden, M. Intramycellular Lipid Concentrations are Correlated with Insulin Sensitivity in Humans: A 1

H NMR Spectroscopy Study. Diabetologia, 1999, 42, 113-116. DOI:10.1007/s001250051123

39. Dragunski, D. C.; Pawlicka, A. Preparation and characterization of starch grafted with toluene poly (propylene

oxide)

diisocyanate.

Materials

Research,

2001,

4

(2),

77-81.

http://dx.doi.org/10.1590/S1516-14392001000200006

40. Tizzoti, M. J.; Sweedman, M. C.; Tang, D.; Schaefer, C.; Gilbert, R. G. New 1H NMR Procedure for the Characterization of Native and Modified Food-Grade Starches. J. Agric. Food Chem. 2011, 59, 6913-6919. DOI: 10.1021/jf201209z

41. Mohamed, M. H.; Wilson, L. D.; Headley, J. V. Design and Characterization of β-Cyclodextrin Based Copolymer

Materials.

Carbohydr.

Res.

2011,

346,

219-229.

https://doi.org/10.1016/j.carres.2010.11.022

42. Liu, H.; Xie, F.; Yu, L.; Chen, L.; Li, L. Thermal processing of starch-based polymers. Prog. Polym. Sci. 2009, 34 (12), 1348-1368. https://doi.org/10.1016/j.progpolymsci.2009.07.001

43. Eliasson, A-C. Interactions between starch and lipids studied by DSC. Thermochim. Acta. 1994, 246, 343-356. https://doi.org/10.1016/0040-6031(94)80101-0

44. Abu-Hardan, M. O.; Hill, S. E.; Farhat, I. A. A calorimetric study of the interaction between Waxy Maize starch and lipid. Starch/Stärke 2007, 59, 217–223. DOI 10.1002/star.200600576

45. Ewa Nebesny, E.; Rosicka, J.; Tkaczyk, M. Influence of Selected Parameters of Starch Gelatinization and Hydrolysis on Stability of Amylose-Lipid Complexes. Starch/Stärke 2005, 57, 325–331. DOI 10.1002/star.200400375

46. Ghiasi, K.; Varriano-Marston, E.; Hoseney, R. C. Gelatinization of Wheat Starch. II. Starch-Surfactant Interaction. Cereal Chem. 1982, 59, 86-88.

ACS Paragon Plus Environment

ACS Sustainable Chemistry & Engineering 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 30 of 34

30

47. Manca, M.; Woortman, A. J. J.; Mura, A.; Loos, K.; Loi, M. A. Localization and dynamics of amylose– lipophilic molecules inclusion complex formation in starch granules. Phys. Chem. Chem. Phys. 2015, 17(12), 7864-7871. DOI: 10.1039/C4CP05001K

48. Dürrenberger, M. B.; Handschin, S.; Conde-Petit, B.; Escher, F. Visualization of Food Structure by Confocal Laser Scanning Microscopy (CLSM). LWT - J. Food Sci. Technol. 2001, 34(1), 11-17. https://doi.org/10.1006/fstl.2000.0739

49. Velde van de, F.; Weinbreck, F.; Edelman, M. W.; Linden van der, E.; Tromp, R. H. Visualisation of biopolymer mixtures using confocal scanning laser microscopy (CSLM) and covalent labelling techniques. Colloids Surf. B 2003, 31, 159-168. https://doi.org/10.1016/S0927-7765(03)00135-8

50. Ovecka, M.; Bahaji, A.; Muñoz, F. J.; Almagro, G.; Ezquer, I.; Baroja-Fernández, E.; Li, J.; Pozueta-Romero, Javier. A sensitive method for confocal fluorescence microscopic visualization of starch granules in iodine stained samples. Plant Signal Behav. 2012, 7(9), 1146–1150. https://doi.org/10.4161/psb.21370

51. Waduge, R. N.; Xu, S.; Seetharaman, K. Iodine absorption properties and its effect on the crystallinity of

developing

wheat

starch

granules.

Carbohydr.

Polym.

2010,

82,

786-794.

https://doi.org/10.1016/j.carbpol.2010.05.053

52. Morrison, W.R. Starch Lipids and How They Relate to Starch Granule Structure and Functionality. CFW 1995, 40, 437-446.

53. Manca, M.; Woortman, A. J. J.; Loos, K.; Loi, M. A. Imaging inclusion complex formation in starch granules using confocal laser scanning microscopy. Starch/Stärke 2015, 67, 132–138. DOI: 10.1002/star.201400118

54. Ayad, M. M.; El-Nasr A. A. Adsorption of Cationic Dye (Methylene Blue) from Water Using Polyaniline

Nanotubes

Base.

J.

Phys.

Chem.

C

2010,

114

(34),

14377–14383.

DOI: 10.1021/jp103780w

55. Sing, K. The use of nitrogen adsorption for the characterisation of porous materials. Colloids Surf. A: Physicochem. Eng. Asp. 2001, 187–188, 3–9. https://doi.org/10.1016/S0927-7757(01)00612-4

56. Mohamed, M. H.; Wilson, L. D.; Pratt, D. Y.; Guo, R.; Wub, C.; Headley, J. V. Evaluation of the accessible inclusion sites in copolymer materials containing β–cyclodextrin. Carbohydr. Polym. 2012, 87, 1241–1248.

57. Mohamed, M. H.; Wilson, L. D. Sequestration of Agrochemicals from Aqueous Media Using Crosslinked Chitosan-based Sorbents. Adsorption, 2016, 22, 1025–1034. https://doi.org/10.1007/s10450016-9796-7

ACS Paragon Plus Environment

Page 31 of 34 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

ACS Sustainable Chemistry & Engineering

31

58. Jawad, A. H.; Sabar, S.; Ishak, M. A. M.; Wilson, L. D.; Norrahma, S. S. A.; Talari M. K.; Farhan, A. M. Microwave-Assisted Preparation of Mesoporous Activated Carbon From Coconut (Cocos Nucifera) Leaf by H3PO4-Activation for Methylene Blue Adsorption. Chem. Eng. Commun. 2017, 204(10), 11431156. https://doi.org/10.1080/00986445.2017.1347565

59. Samiey, B.; Ashoori, F. Adsorptive removal of methylene blue by agar: effects of NaCl and ethanol. Chem. Cent. J. 2012, 6(14), 1-13. doi: 10.1186/1752-153X-6-14

60. Dehabadi, L.; Udoetok, I. A.; Wilson, L. D. Macromolecular hydration phenomena. J. Therm. Anal. Calorim. 2016, 126, 1851–1866. DOI 10.1007/s10973-016-5673-6

61. Fathieh, F.; Dehabadi, L.; Wilson, L. D.; Besant, R. W.; Evitts, R. W. Simonson, C. J. Sorption Study of a Starch Biopolymer as an Alternative Desiccant for Energy Wheels. ACS Sustainable Chem. Eng. 2016, 4 (3), 1262–1273. DOI: 10.1021/acssuschemeng.5b01301

62. Fang, Y-Y.; Wang, L-j.; Li, D.; Li, B-z.; Bhandari, B.; Chen, X. D.; Mao, Z-H. Preparation of crosslinked starch microspheres and their drug loading and releasing properties. Carbohydr. Polym. 2008, 74, 379–384. https://doi.org/10.1016/j.carbpol.2008.03.005

63. Glenn, G. M.; Klamczynski, A. P.; Woods, D. F.; Chiou, B.; Orts, W. J.; Imam, S. H. Encapsulation of Plant Oils in Porous Starch Microspheres. J. Agric. Food Chem. 2010, 58 (7), 4180–4184. DOI: 10.1021/jf9037826

64. Larsen, F. H.; Blennow, A.; Engelsen, S. B. Starch granule hydration – A MAS NMR investigation. Food Biophys. 2008, 3, 25–32.

65. Elvira, C.; Mano, J. F.; Roman, J. S.; Reis, R. L. Starch-based biodegradable hydro gels with potential biomedical applications as drug delivery systems. Biomaterials, 2002, 23, 1955-1966. https://doi.org/10.1016/S0142-9612(01)00322-2

66. Kyzas, G. Z.; Bikiaris, D.N.; Lazaridis, N. K. Low-swelling chitosan derivatives as biosorbents for basic dyes. Langmuir, 2008, 24, 4791–4799. DOI: 10.1021/la7039064

67. Wojtasz, J.; Carlstedt, J.; Fyhr, P.; Kocherbitov, V. Hydration and swelling of amorphous cross-linked starch

microspheres.

Carbohydr.

Polym.

2016,

135,

225–233.

https://doi.org/10.1016/j.carbpol.2015.08.085

68. Meroufel, B.; Benali, O.; Benyahia, M.; Benmoussa, Y.; Zenasni, M. A. Adsorptive removal of anionic dye from aqueous solutions by Algerian kaolin: Characteristics, isotherm, kinetic and thermodynamic studies. J. Mater. Environ. Sci. 2013, 4 (3), 482-491. DOI: 10.5829/idosi.ijee.2015.06.02.11

69. Karoyo, A. H.; Wilson, L. D. Investigation of the Adsorption Processes of Fluorocarbon and Hydrocarbon Anions at the Solid–Solution Interface of Macromolecular Imprinted Polymer Materials. J. Phys. Chem. C. 2016, 120(12), 6553-6568. DOI: 10.1021/acs.jpcc.5b12246

ACS Paragon Plus Environment

ACS Sustainable Chemistry & Engineering 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 32 of 34

32

70. Ghasemian, J.; Miladi, M. Association equilibrium of methylene blue by spectral titration and chemometrics analysis. A thermodynamic study. J. Chin. Chem. Soc. 2009, 56, 459-468. DOI: 10.1002/jccs.200900069

71. Huang, X.; Yang, J.; Zhang, W.; Zhang, Z.; An, Z. Determination of the Critical Micelle Concentration of Cationic Surfactants: An Undergraduate Experiment. J. Chem. Educ. 1999, 76(1), 93-94. DOI: 10.1021/ed076p93

72. Bergmann, K.; Konski, C. T. A spectroscopic study of methylene blue monomer, dimer, and complexes with montmorillonite. J. Phys. Chem. 1963, 67, 2169-77. DOI: 10.1021/j100804a048

73. Hameed, B. H.; Ahmad, A. A. Batch adsorption of methylene blue from aqueous solution by garlic peel, an agricultural waste biomass. J. Hazard. Mater. 2009, 164, 870–875. DOI: 10.1016/j.jhazmat.2008.08.084

74. Vadivelan, V.; Kumar, K. Equilibrium, kinetics, mechanism, and process design for the sorption of methylene

blue

onto

rice

husk.

J.

Colloid

Interf.

Sci.

2005,

286,

90–100.

https://doi.org/10.1016/j.jcis.2005.01.007

75. Batzias, F. A.; Sidiras, D.K. Dye adsorption by calcium chloride treated beech sawdust in batch and fixed-bed

systems.

J.

Hazard.

Mater.

2004,

B114,

167–174.

https://doi.org/10.1016/j.jhazmat.2004.08.014

76. Hameed, B. H.; El-Khaiary, M. I. Batch removal of malachite green from aqueous solutions by adsorption on oil palm trunk fibre: equilibrium isotherms and kinetic studies. J. Hazard. Mater. 2008, 154, 237–244. https://doi.org/10.1016/j.jhazmat.2007.10.017

77. Guo, L.; Li, L.; Liu, J.; Meng, Y.; Tang, Y. Adsorptive decolorization of methylene blue by crosslinked porous starch. Carbohydr. Polym. 2013, 93, 374-379. https://doi.org/10.1016/j.carbpol.2012.12.019

78. Lozinska, M. M.; Mowat, J. P. S.; Wright, P. A.; Thompson, S. P.; Jorda, J. L.; Palomino, M.; Valencia, S.; Rey, F. Cation Gating and Relocation during the Highly Selective “Trapdoor” Adsorption of CO 2 on Univalent Cation Forms of Zeolite Rho. Chem. Mater., 2014, 26 (6), 2052–2061. DOI: 10.1021/cm404028f

79. Guo, R.; Wilson, L. D. Synthetically engineered chitosan-Based materials and their sorption properties with Methylene Blue in aqueous solution. J. Colloid Interface Sci. 2012, 388, 225–234. DOI: 10.1016/j.jcis.2012.08.010

ACS Paragon Plus Environment

Page 33 of 34 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

ACS Sustainable Chemistry & Engineering

33

TOC Graphic

Left: Bar graphs showing swelling of starch particles (SPs) in water and ethanol. Right: Higher adsorption capacity of pure methylene blue (MB) with SPs (Red curve) due to accessibility of the active sites by MB (see scheme on top right); and reduced adsorption of cetylpyridium (CPB)-bound MB (Black curve) due to modification of the SP-surface via self-assembly of the surfactant (see scheme on bottom right).

ACS Paragon Plus Environment

ACS Sustainable Chemistry & Engineering 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

Left: Bar graphs showing swelling of starch particles (SPs) in water and ethanol. Right: Higher adsorption capacity of pure methylene blue (MB) with SPs (Red curve) due to accessibility of the active sites by MB (see scheme on top roght); and reduced adsorption of cetylpyridium (CPB)-bound MB (Black curve) due to modification of the SP-surface via self-assembly of the surfactant (see scheme on bottom right). 338x190mm (96 x 96 DPI)

ACS Paragon Plus Environment

Page 34 of 34