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He G, Wen G, Skandalis A, Pispas S, Liu D. Effects of ionic strength and ion-specificity on the interface behavior of PDMAEMA-b-PLMA-b-POEGMA triblock terpolymer. Colloids Surf A Physicochem Eng Asp 2022. [DOI: 10.1016/j.colsurfa.2022.130659] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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2
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Liu D, Wen G, Skandalis A, Pispas S, He G, Zhang W. Aggregation behavior of triblock terpolymer poly[
n
‐butyl acrylate‐
block
‐
N
‐isopropylacrylamide‐
block
‐2‐(dimethylamino)ethyl acrylate] at the air/water interface. J Appl Polym Sci 2022. [DOI: 10.1002/app.52989] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Dongxue Liu
- Department of Polymer Materials and Engineering, College of Material Science and Chemical Engineering Harbin University of Science and Technology Harbin People's Republic of China
| | - Gangyao Wen
- Department of Polymer Materials and Engineering, College of Material Science and Chemical Engineering Harbin University of Science and Technology Harbin People's Republic of China
| | - Athanasios Skandalis
- Theoretical and Physical Chemistry Institute National Hellenic Research Foundation Athens Greece
| | - Stergios Pispas
- Theoretical and Physical Chemistry Institute National Hellenic Research Foundation Athens Greece
| | - Guanying He
- Department of Polymer Materials and Engineering, College of Material Science and Chemical Engineering Harbin University of Science and Technology Harbin People's Republic of China
| | - Wang Zhang
- Department of Polymer Materials and Engineering, College of Material Science and Chemical Engineering Harbin University of Science and Technology Harbin People's Republic of China
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3
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Yang S, Wen G, Pispas S, You K. Effects of spreading and subphase conditions on the interfacial behavior of an amphiphilic copolymer poly(n-butylacrylate)-b-poly(acrylic acid). POLYMER 2019. [DOI: 10.1016/j.polymer.2019.03.060] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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4
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Matsuoka H, Uda K. Nanostructure of Poly(N-isopropylacrylamide) Brush at the Air/Water Interface and Its Responsivity to Temperature and Salt. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2016; 32:8383-8391. [PMID: 27467013 DOI: 10.1021/acs.langmuir.6b01752] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Nanostructure and transition of the poly(N-isopropylacrylamide (PNIPAm) brush at the air/water interface were investigated by π-A isotherm and X-ray reflectivity, and an interesting behavior was observed with the change in temperature and salt. The polymer monolayer of poly(n-butyl acrylate)(PnBA)-b-PNIPAm on the water surface showed a transition between carpet-only/carpet+brush structures as a function of brush density, which was controlled by compression/expansion, as was the case for ionic brush systems. The brush stretching factor was about 50%, which was slightly less than that for a strongly ionic brush. The number of water molecules inside the brush layer was estimated to be 11-13 per repeating unit of PNIPAm chain. This value is very close to the number of hydrated water molecules reported, which means that all the water molecules inside the brush layer were hydrated water. With elevating temperature, the PNIPAm brush shrank, and the number of water molecules in the brush layer was reduced to 3. These observations certainly indicated a dehydration process. Interestingly, a part of the PNIAPm chain formed a "hydrophobic PNIPAm layer" on the carpet layer under the PnBA hydrophobic layer. A similar transition was observed also by the addition of salt to the water subphase. Although the formation of "hydrophobic PNIPAm layer" was not observed in this case, shrinking of the brush was observed with increasing salt concentration, and finally it became a carpet-only structure, which contained no water molecules. This salt effect was found to be ion specific, and its effectiveness was in the order of F(-) > Cl(-) > Br(-), which is in agreement with the Hofmeister series.
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Affiliation(s)
- Hideki Matsuoka
- Department of Polymer Chemistry, Kyoto University , Kyoto 615-8510, Japan
| | - Kyohei Uda
- Department of Polymer Chemistry, Kyoto University , Kyoto 615-8510, Japan
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5
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Xu S, Ping Z, Xu X, Zhang L. Changes in shape and size of the stiff branched β-glucan in dimethlysulfoxide/water solutions. Carbohydr Polym 2016; 138:86-93. [DOI: 10.1016/j.carbpol.2015.11.049] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2015] [Revised: 10/25/2015] [Accepted: 11/18/2015] [Indexed: 01/14/2023]
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6
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Li ZB, Xiang YH, Zhou XJ, Nie JJ, Peng M, Du BY. Thermo-sensitive poly(DEGMMA-co-MEA) microgels: Synthesis, characterization and interfacial interaction with adsorbed protein layer. CHINESE JOURNAL OF POLYMER SCIENCE 2015. [DOI: 10.1007/s10118-015-1694-z] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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7
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Crawford NF, Micic M, Orbulescu J, Weissbart D, Leblanc RM. Surface chemistry and spectroscopy of the β-galactosidase Langmuir monolayer. J Colloid Interface Sci 2015; 453:202-208. [DOI: 10.1016/j.jcis.2015.04.063] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2015] [Revised: 04/29/2015] [Accepted: 04/29/2015] [Indexed: 01/05/2023]
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8
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Xu W, Ledin PA, Iatridi Z, Tsitsilianis C, Tsukruk VV. Multiresponsive Star-Graft Quarterpolymer Monolayers. Macromolecules 2015. [DOI: 10.1021/acs.macromol.5b00401] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Affiliation(s)
- Weinan Xu
- School
of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332-0245, United States
| | - Petr A. Ledin
- School
of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332-0245, United States
| | - Zacharoula Iatridi
- Department
of Chemical Engineering, University of Patras, 26504 Patras, Greece
- Institute of Chemical
Engineering Sciences (FORTH/ICE-HT), 26504 Patras, Greece
| | - Constantinos Tsitsilianis
- Department
of Chemical Engineering, University of Patras, 26504 Patras, Greece
- Institute of Chemical
Engineering Sciences (FORTH/ICE-HT), 26504 Patras, Greece
| | - Vladimir V. Tsukruk
- School
of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332-0245, United States
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9
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Molecular arrangement of symmetric and non-symmetric triblock copolymers of poly(ethylene oxide) and poly(isobutylene) at the air/water interface. J Colloid Interface Sci 2015; 437:80-89. [PMID: 25313470 DOI: 10.1016/j.jcis.2014.09.050] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2014] [Revised: 09/12/2014] [Accepted: 09/15/2014] [Indexed: 12/16/2022]
Abstract
The behavior of a series of amphiphilic triblock copolymers of poly(ethylene oxide) (PEO) and poly(isobutylene) (PIB); including both symmetric (same degree of polymerization (DP) of the terminal PEO blocks) PEOm-b-PIBn-b-PEOm and non-symmetric (different DP of the terminal PEO blocks) PEOm-b-PIBn-b-PEOz, is investigated at the air/water interface by measuring surface pressure vs mean molecular area isotherms (π vs mmA), Langmuir-Blodgett (LB) technique, and infrared reflection-absorption spectroscopy (IRRAS). The block copolymer (PEO32-b-PIB160-b-PEO32) with longer PEO segments forms a stable monolayer and the isotherm reveals a pseudo-plateau starting at π∼5.7 mN/m, also observed in the IRRAS, which is assigned to the pancake-to-brush transition related to the PEO dissolution into the subphase and subsequent PEO brush dehydration. Another plateau is observed at π∼40 mN/m, which is attributed to the film collapse due to multilayer formation. The pancake-to-brush transition could not be observed for samples with smaller PEO chains. The isotherms for block copolymers, with short PEO chains, both symmetric (PEO3-b-PIBn-b-PEO3) and non-symmetric (PEO12-b-PIBn-b-PEO3), reveal another transition at π∼20-25 mN/m. This is interpreted to be due to the conformational transition from a folded state where the middle PIB block is anchored to the water surface at both ends by the terminal hydrophilic segments to an unfolded state with PIB anchored to the water surface at one end. It is assumed that this transition involves the removal of PEO3 chains from the water surface in case of non-symmetric PEO12-b-PIB85-b-PEO3 and in case of symmetric, probably one PEO3 of each PEO3-b-PIB85-b-PEO3 chain. Because of the weaker interaction of the short PEO3 chains with the water surface as compared with the relatively longer PEO12 chains, the film of PEO3-b-PIB85-b-PEO3 collapses at much lower surface pressure after the transition as compared with the PEO12-b-PIB85-b-PEO3. The AFM images reveal the formation of microdomains of almost uniform height (6-7 nm) in LB films of PEO3-b-PIB85-b-PEO3 and PEO12-b-PIB85-b-PEO3 after transferring onto silicon surfaces. These domains are assumed to be the mesomorphic domains of ordered and folded PIB chains.
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10
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Pinaud F, Geisel K, Massé P, Catargi B, Isa L, Richtering W, Ravaine V, Schmitt V. Adsorption of microgels at an oil-water interface: correlation between packing and 2D elasticity. SOFT MATTER 2014; 10:6963-6974. [PMID: 24825608 DOI: 10.1039/c4sm00562g] [Citation(s) in RCA: 106] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
The aim of this paper is to determine how microgels adsorb at a model oil-water interface and how they adapt their conformation to compression, which gives rise to surface elasticity depending on the microgel packing. The structure of the film is determined by the Langmuir films approach (forced compression) and compared to spontaneous adsorption using the pendant drop method. The behaviour of microgels differs significantly from that of non-deformable particles but resembles that of linear polymers or proteins. We also correlate the properties of microgels spontaneously adsorbed at model interfaces to their forced adsorption during emulsification. Finally we propose a route to easily control a posteriori the microgel packing at the surface of droplets and the flow properties of emulsions stabilised by the microgels.
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Affiliation(s)
- Florent Pinaud
- Université de Bordeaux, Institut des Sciences Moléculaires, ENSCBP, 16 Av. Pey Berland, 33607 Pessac Cedex, France.
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11
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Effect of temperature on surface pressure–area isotherms and surface dilational moduli of poly(N-isopropyl acrylamide) monolayers spread at air–water interface. Colloids Surf A Physicochem Eng Asp 2014. [DOI: 10.1016/j.colsurfa.2014.06.028] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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12
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Okumura Y, Kawaguchi M. Surface pressure–area isotherms and surface dilational moduli of poly (N-isopropyl acrylamide) monolayers spread at air–water interface. Colloids Surf A Physicochem Eng Asp 2014. [DOI: 10.1016/j.colsurfa.2013.09.015] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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13
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Xu S, Xu X, Zhang L. Effect of Heating on Chain Conformation of Branched β-Glucan in Water. J Phys Chem B 2013; 117:8370-7. [DOI: 10.1021/jp403202u] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Affiliation(s)
- Shuqin Xu
- Department
of Chemistry, Wuhan University, Wuhan 430072,
China
| | - Xiaojuan Xu
- Department
of Chemistry, Wuhan University, Wuhan 430072,
China
| | - Lina Zhang
- Department
of Chemistry, Wuhan University, Wuhan 430072,
China
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14
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Lin HC, Hsieh BZ, Lin YL, Sheng YJ, Lin JJ. Effect of grafting architecture on the surfactant-like behavior of clay-poly(NiPAAm) nanohybrids. J Colloid Interface Sci 2012; 387:106-14. [DOI: 10.1016/j.jcis.2012.07.084] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2012] [Revised: 07/26/2012] [Accepted: 07/26/2012] [Indexed: 10/28/2022]
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15
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Volden S, Ese MHG, Zhu K, Yasuda M, Nyström B, Glomm WR. Interactions between bovine serum albumin and Langmuir films composed of charged and uncharged poly(N-isopropylacrylamide) block copolymers. Colloids Surf B Biointerfaces 2012; 98:50-7. [DOI: 10.1016/j.colsurfb.2012.04.038] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2011] [Revised: 03/30/2012] [Accepted: 04/26/2012] [Indexed: 11/26/2022]
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16
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Yi G, Zhu Z, Wang F, Chen X, Yang J, Huang Y. Study of Phase Separation of Poly(N-isopropylacrylamide-co-styrene) Aqueous Solutions with Rayleigh Scattering Technique. CHINESE J CHEM 2011. [DOI: 10.1002/cjoc.201190177] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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17
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DU BY, FAN X, CAO Z, GUO XL. Applications and Outlooks of Quartz Crystal Microbalance in Studies of Polymer Thin Films. CHINESE JOURNAL OF ANALYTICAL CHEMISTRY 2010. [DOI: 10.3724/sp.j.1096.2010.00752] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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18
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19
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Temperature-dependent interfacial properties of hydrophobically end-modified poly(2-isopropyl-2-oxazoline)s assemblies at the air/water interface and on solid substrates. J Colloid Interface Sci 2009; 340:142-52. [DOI: 10.1016/j.jcis.2009.06.060] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2009] [Revised: 06/23/2009] [Accepted: 06/24/2009] [Indexed: 11/22/2022]
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20
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Thakur G, Micic M, Leblanc RM. Surface chemistry of Alzheimer's disease: a Langmuir monolayer approach. Colloids Surf B Biointerfaces 2009; 74:436-56. [PMID: 19726167 DOI: 10.1016/j.colsurfb.2009.07.043] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2009] [Revised: 07/28/2009] [Accepted: 07/29/2009] [Indexed: 12/14/2022]
Abstract
Amyloid beta (1-40) and (1-42) peptides are the major constituents of hallmark senile plaques found in Alzheimer's disease (AD) patients. Study of aggregation of Abeta (1-40) and (1-42) peptides and the truncated Abeta fragments could lead towards the mechanism of AD. Langmuir monolayer approach is one of the excellent methods to investigate the mechanism and origin of AD. Particularly, to study the steps involved in the formation and assembly of beta-sheet structures leading to formation of amyloid fibrils. Surface pressure- and surface potential-area isotherms provide information regarding the nature of short-range and long-range interactions between the molecules especially the lipids and the Abeta peptides. Spectroscopic methods like IRRAS, PM-IRRAS, FTIR-ATR, and GIXD at the air-water interface provide insight into the structural characterization, and orientation of the molecules in the Langmuir monolayer.
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Affiliation(s)
- Garima Thakur
- Department of Chemistry, University of Miami, 1301 Memorial Drive, Coral Gables, FL 33146, United States
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21
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Zhang Y, Du B, Chen X, Ma H. Convergence of dissipation and impedance analysis of quartz crystal microbalance studies. Anal Chem 2009; 81:642-8. [PMID: 19072247 DOI: 10.1021/ac8019762] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A quartz crystal microbalance (QCM) consists of a resonator, which measures the resonance frequency of the quartz slab. When coupled with a network analyzer or coupled with impulse excitation technology, QCM gives additional impedance or dissipation information, respectively. This report provides a set of equations that bring the QCM community a convergence of the dissipation and impedance analysis. Equations derived from the complex frequency shift were applied to quantitatively analyze the dissipation data of polymer brushes obtained from QCM-D. The obtained viscoelastic properties of polymer brushes were then compared with those obtained by the Voigt model method. We believe that these equations will be useful in quantitative studies of interfacial phenomena accompanied with mass or viscoelasticity changes.
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Affiliation(s)
- Yaozhong Zhang
- Key Laboratory of Macromolecular Synthesis and Functionalization (Ministry of Education), Department of Polymer Science & Engineering, Zhejiang University, Hangzhou 310027, USA
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22
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Dai R, Zhang X, Hu N, Liu Y, Deng Y. Preparation and characterization of temperature-responsive capillary electrochromatographic column using poly(N-isopropylacrylamide). Electrophoresis 2009; 30:616-7. [DOI: 10.1002/elps.200800705] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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23
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Thermo-responsiveness of poly(-diethylacrylamide) polymers at the air–water interface: The effect of a hydrophobic block. J Colloid Interface Sci 2008; 327:129-37. [DOI: 10.1016/j.jcis.2008.08.011] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2008] [Revised: 07/28/2008] [Accepted: 08/01/2008] [Indexed: 11/20/2022]
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24
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Cabasso I, Stesikova E. Amphiphilic Siloxane Phosphonate Macromolecule Monolayers at the Air/Water Interface: Effects of Structure and Temperature. J Phys Chem B 2008; 112:14379-89. [DOI: 10.1021/jp801557g] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Israel Cabasso
- The Michael Szwarc Polymer Research Institute, Department of Chemistry State University of New York - esf, Syracuse, New York 13210
| | - Elvira Stesikova
- The Michael Szwarc Polymer Research Institute, Department of Chemistry State University of New York - esf, Syracuse, New York 13210
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25
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Cao Z, Du B, Chen T, Li H, Xu J, Fan Z. Fabrication and properties of thermosensitive organic/inorganic hybrid hydrogel thin films. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2008; 24:5543-51. [PMID: 18439032 DOI: 10.1021/la8000653] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
We report on a facile method for fabricating thermosensitive organic/inorganic hybrid hydrogel thin films from a cross-linkable organic/inorganic hydrid copolymer, poly[ N-isopropylacrylamide- co-3-(trimethoxysilyl)propylmethacrylate] [P(NIPAm- co-TMSPMA)]. Fourier transform infrared (FT-IR) spectra confirmed the formation of hybrid hydrogel thin films after hydrolysis of the methoxysilyl groups (Si-O-CH 3) and subsequent condensation of the silanol groups (Si-OH). Atomic force microscopy (AFM) images revealed that the surface morphology of the hydrogel thin films depended on the supporting substrates. Microdomains were observed for the hydrogel thin films on a gold surface, which can be attributed to inhomogeneous network structures. The thermoresponsive swelling-deswelling behavior and the viscoelastic properties of the hydrogel thin films were investigated as a function of temperature (25-45 degrees C) by using a quartz crystal microbalance (QCM) operated in water. The high frequency shear modulus of the P(NIPAm- co-TMPSMA) hydrogel thin films was several hundred kilopascals.
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Affiliation(s)
- Zheng Cao
- Department of Polymer Science and Engineering, Zhejiang University, Hangzhou, China
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26
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Shankar BV, Patnaik A. Equilibrium structure and dynamics of (2R, 3R)-(+)-bis(decyloxy)succinic acid at the air-water interface. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2008; 24:758-766. [PMID: 18177056 DOI: 10.1021/la701998c] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
A twin-tailed, twin-chiral fatty acid, (2R,3R)-(+)-bis(decyloxy)succinic acid was synthesized and its two dimensional behavior at the air-water interface was examined. The pH of the subphase had a profound effect on the monolayer formation. On acidic subphase, stable monolayers with increased area per molecule due to hydrogen bonding and bilayers at collapse pressures were observed. Highly compressible films were formed at 40 degrees C, while stable monolayers with increased area were observed at sub-room temperatures. Langmuir monolayers formed on subphases containing 1 mM ZnCl2 and CaCl2 revealed two dimensional metal complex formation with Zn2+ forming a chelate-type complex, while Ca2+ formed an ionic-type complex. Monolayers transferred from the condensed phase onto hydrophilic Si(100) and quartz substrates revealed the formation of bilayers through transfer-induced monolayer buckling. Compression induced crystallites in 2D from monolayers and vesicle-like supramolecular structures from multilayers were the noted LB film characteristics, adopting optical imaging and electron microscopy. The interfacial monolayer structure studied through molecular dynamics simulation revealed the order and packing at a molecular level; monolayers adsorbed at various simulated specific areas of the molecule corroborated the (pi-A) isotherm and the formation of a hexagonal lattice at the air-water interface.
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Affiliation(s)
- B Vijai Shankar
- Department of Chemistry, Indian Institute of Technology Madras, Chennai 600036, India
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27
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Liu G, Chen Y, Zhang G, Yang S. Protein resistance of (ethylene oxide)n monolayers at the air/water interface: effects of packing density and chain length. Phys Chem Chem Phys 2007; 9:6073-82. [PMID: 18167582 DOI: 10.1039/b711037e] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Protein adsorption on poly(ethylene oxide) (PEO) and oligo(ethylene oxide) (OEO) monolayers is studied at different packing densities using the Langmuir technique. In the case of a PEO monolayer, a protein adsorption minimum is revealed at sigma(-1) = 10 nm(2) for both lysozyme and fibrinogen. Manifested are two packing density regimes of steric repulsion and compressive attraction between PEO and a protein on top of the overall attraction of the protein to the air/water interface. The observed protein adsorption minimum coincides with the maximum of the surface segment density at sigma(-1) = 10 nm(2). However, OEO monolayer presents a different scenario, namely that the amount of protein adsorbed decreases monotonically with increasing packing density, indicating that the OEO chains merely act as a steric barrier to protein adsorption onto the air/water interface. Besides, in the adsorption of fibrinogen, three distinct kinetic regimes controlled by diffusion, penetration and rearrangement are recognized, whereas only the latter two were made out in the adsorption of lysozyme.
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Affiliation(s)
- Guangming Liu
- Department of Chemistry, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China
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