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Lesniewska N, Beaussart A, Duval JF. Electrostatics of soft (bio)interfaces: Corrections of mean-field Poisson-Boltzmann theory for ion size, dielectric decrement and ion-ion correlation. J Colloid Interface Sci 2023; 642:154-168. [PMID: 37003010 DOI: 10.1016/j.jcis.2023.03.027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2022] [Revised: 02/24/2023] [Accepted: 03/02/2023] [Indexed: 03/28/2023]
Abstract
HYPOTHESIS Electrostatics of soft (ion-permeable) (bio)particles (e.g. microorganisms, core/shell colloids) in aqueous electrolytes is commonly formulated by the mean-field Poisson-Boltzmann theory and integration of the charge contributions from electrolyte ions and soft material. However, the effects connected to the size of the electrolyte ions and that of the structural charges carried by the particle, to dielectric decrement and ion-ion correlations on soft interface electrostatics have been so far considered at the margin, despite the limits of the Gouy theory for condensed and/or multivalent electrolytes. EXPERIMENTS Accordingly, we modify herein the Poisson-Boltzmann theory for core/shell (bio)interfaces to include the aforementioned molecular effects considered separately or concomitantly. The formalism is applicable for poorly to highly charged particles in the thin electric double layer regime and to unsymmetrical multivalent electrolytes. FINDINGS Computational examples of practical interests are discussed with emphasis on how each considered molecular effect or combination thereof affects the interfacial potential distribution depending on size and valence of cations and anions, size of particle charges, length scale of ionic correlations and shell-to-Debye layer thickness ratio. The origins of here-evidenced pseudo-harmonic potential profile and ion size-dependent screening of core/shell particle charges are detailed. In addition, the existence and magnitude of the Donnan potential when reached in the shell layer are shown to depend on the excluded volumes of the electrolyte ions.
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2
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Fan ZW, Jin XL, Chen Y, Lu M, Wang YR, Yue K, Wen T, Tang L, Wu ZL, Sun T. Topology and Dynamic Regulations of Comb-like Polymers as Strong Adhesives. Macromolecules 2023. [DOI: 10.1021/acs.macromol.2c01851] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
Affiliation(s)
- Zhi Wei Fan
- South China Advanced Institute for Soft Matter Science and Technology, School of Emergent Soft Matter, South China University of Technology, Guangzhou 510640, China
- Guangdong Provincial Key Laboratory of Functional and Intelligent Hybrid Materials and Devices, South China University of Technology, Guangzhou 510640, China
| | - Xiao Lin Jin
- South China Advanced Institute for Soft Matter Science and Technology, School of Emergent Soft Matter, South China University of Technology, Guangzhou 510640, China
- Guangdong Provincial Key Laboratory of Functional and Intelligent Hybrid Materials and Devices, South China University of Technology, Guangzhou 510640, China
| | - Yang Chen
- South China Advanced Institute for Soft Matter Science and Technology, School of Emergent Soft Matter, South China University of Technology, Guangzhou 510640, China
- Guangdong Provincial Key Laboratory of Functional and Intelligent Hybrid Materials and Devices, South China University of Technology, Guangzhou 510640, China
| | - Mengze Lu
- South China Advanced Institute for Soft Matter Science and Technology, School of Emergent Soft Matter, South China University of Technology, Guangzhou 510640, China
- Guangdong Provincial Key Laboratory of Functional and Intelligent Hybrid Materials and Devices, South China University of Technology, Guangzhou 510640, China
| | - Yi Ru Wang
- South China Advanced Institute for Soft Matter Science and Technology, School of Emergent Soft Matter, South China University of Technology, Guangzhou 510640, China
- Guangdong Provincial Key Laboratory of Functional and Intelligent Hybrid Materials and Devices, South China University of Technology, Guangzhou 510640, China
| | - Kan Yue
- South China Advanced Institute for Soft Matter Science and Technology, School of Emergent Soft Matter, South China University of Technology, Guangzhou 510640, China
- Guangdong Provincial Key Laboratory of Functional and Intelligent Hybrid Materials and Devices, South China University of Technology, Guangzhou 510640, China
| | - Tao Wen
- South China Advanced Institute for Soft Matter Science and Technology, School of Emergent Soft Matter, South China University of Technology, Guangzhou 510640, China
- Guangdong Provincial Key Laboratory of Functional and Intelligent Hybrid Materials and Devices, South China University of Technology, Guangzhou 510640, China
| | - Liqun Tang
- School of Civil Engineering and Transportation, South China University of Technology, No. 381, Wushan Road, Guangzhou 510640, China
| | - Zi Liang Wu
- Ministry of Education Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou 310027, China
| | - Taolin Sun
- South China Advanced Institute for Soft Matter Science and Technology, School of Emergent Soft Matter, South China University of Technology, Guangzhou 510640, China
- Guangdong Provincial Key Laboratory of Functional and Intelligent Hybrid Materials and Devices, South China University of Technology, Guangzhou 510640, China
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3
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Electrostatic effects on ligand-assisted transfer of metals to (bio)accumulating interfaces and metal complexes (bioavai)lability. Colloids Surf A Physicochem Eng Asp 2022. [DOI: 10.1016/j.colsurfa.2022.130679] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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4
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Geonzon LC, Kobayashi M, Sugimoto T, Adachi Y. Interaction between silica particles with poly(ethylene oxide) studied using an optical tweezer: insignificant effect of poly(ethylene oxide) on long-range double layer interaction. Colloid Polym Sci 2022. [DOI: 10.1007/s00396-022-05020-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Saha S, Adachi Y. Shielding behavior of electrokinetic properties of polystyrene latex particle by the adsorption of neutral poly(ethylene oxide). J Colloid Interface Sci 2022; 626:930-938. [PMID: 35835043 DOI: 10.1016/j.jcis.2022.06.154] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2022] [Revised: 06/10/2022] [Accepted: 06/27/2022] [Indexed: 12/31/2022]
Abstract
To understand the shielding of electrokinetics of colloidal particles by polymer coating, we measured the electrophoretic mobility of negatively charged polystyrene sulfate latex (PSL) adsorbed with electrostatically neutral polyethylene oxide (PEO) chains with various molecular weights under different ionic strengths. We confirmed that substantial adsorbed neutral polymer on the particle surface would decrease the absolute value of electrophoretic mobility. Even though the polymer layer is sufficiently thicker compared to the thickness of electric double layer (EDL), the electrophoretic mobility (EPM) never vanishes, which indicates the incompleteness of electrokinetic shielding by an adsorbed neutral polymer. To relate such interesting phenomena, a simple mathematical model has been proposed to evaluate the electrophoretic mobility, assuming the presence of a scaling structure of adsorbed permeable polymer layer does not influence the Poisson-Boltzmann distribution of ions in the electric double layer (EDL). An analytical expression of electrophoretic mobility under Debye-Hu¨ckel approximation has been derived using the method of Ohshima-Kondo theory, which successfully justifies the experimentally obtained data.
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Affiliation(s)
- Santanu Saha
- Graduate School of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan.
| | - Yasuhisa Adachi
- Graduate School of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan.
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Zimmermann R, Duval JF, Werner C, Sterling JD. Quantitative insights into electrostatics and structure of polymer brushes from microslit electrokinetic experiments and advanced modelling of interfacial electrohydrodynamics. Curr Opin Colloid Interface Sci 2022. [DOI: 10.1016/j.cocis.2022.101590] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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7
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Geonzon LC, Kobayashi M, Sugimoto T, Adachi Y. Study on the kinetics of adsorption of poly(ethylene oxide) onto a silica particle using optical tweezers and microfluidics. Colloids Surf A Physicochem Eng Asp 2022. [DOI: 10.1016/j.colsurfa.2022.128691] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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8
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Ion partitioning effect on the electrostatic interaction between two charged soft surfaces. Colloids Surf A Physicochem Eng Asp 2021. [DOI: 10.1016/j.colsurfa.2021.127296] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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9
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Ifra, Singh A, Saha S. High Adsorption of α-Glucosidase on Polymer Brush-Modified Anisotropic Particles Acquired by Electrospraying-A Combined Experimental and Simulation Study. ACS APPLIED BIO MATERIALS 2021; 4:7431-7444. [PMID: 35006717 DOI: 10.1021/acsabm.1c00682] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
In this particular contribution, we aim to immobilize a model enzyme such as α-glucosidase onto poly(DMAEMA) [poly(2-dimethyl amino ethyl methacrylate)] brush-modified anisotropic (cup- and disc-shaped) biocompatible polymeric particles. The anisotropic particles comprising a blend of PLA [poly(lactide)] and poly(MMA-co-BEMA) [poly((methyl methacrylate)-co-(2-(2-bromopropionyloxy) ethyl methacrylate)] were acquired by electrospraying, a scalable and convenient technique. We have also demonstrated the role of a swollen polymer brush grafted on the surface of cup-/disc-shaped particles via surface-initiated atom transfer radical polymerization in immobilizing an unprecedentedly high loading of enzyme [441 mg/g (cup)-589 mg/g (disc) of particles, 15-20 times higher than that of the literature-reported system] as compared to non-brush-modified particles. Circular dichroism spectroscopy was used to predict the structural changes of the enzyme upon immobilization onto the carrier particles. An enormously high amount of enzymes with preserved activity (∼85 ± 13% for cups and ∼78 ± 15% for discs) was found to adhere onto brush-modified particles at pH 7 via electrostatic adsorption. These findings were further explored at the atomistic level using a coarse-grained dissipative particle dynamics simulation approach, which exhibited excellent correlation with experimental results. In addition, accelerated particle separation was also achieved via magnetic force-induced aggregation within 20 min (without a centrifuge) by incorporating magnetic nanoparticles into disc-shaped particles while electrojetting. This further strengthens the technical feasibility of the process, which holds immense potential to be applied for various enzymes intended for several applications.
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Affiliation(s)
- Ifra
- Department of Materials Science and Engineering, Indian Institute of Technology Delhi, New Delhi 110016, India
| | - Awaneesh Singh
- Department of Physics, Indian Institute of Technology (BHU), Varanasi 221005, India
| | - Sampa Saha
- Department of Materials Science and Engineering, Indian Institute of Technology Delhi, New Delhi 110016, India
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de Los Santos Pereira A, Cernescu A, Svoboda J, Sivkova R, Romanenko I, Bashta B, Keilmann F, Pop-Georgievski O. Conformation in Ultrathin Polymer Brush Coatings Resolved by Infrared Nanoscopy. Anal Chem 2020; 92:4716-4720. [PMID: 32129604 DOI: 10.1021/acs.analchem.9b05661] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Polymer brush coatings are effective in preventing blood coagulation or bacterial attachment, but their chain conformation, while vital for this effect, was never characterized in high spatial resolution. Here, we report mid-infrared spectroscopic nanoscopy studies of few-nanometer-thin poly(ethylene oxide) (PEO) films which reveal marked spectral variations along the surface at a length scale smaller than 100 nm and originating only from the physical conformation of the chains. The conformation and average orientation of the polymer chains in the layer is extracted from the spectra with the aid of theoretic modeling, confirming the spontaneous formation of a crystalline phase. This result suggests spectroscopic nanoscopy as a powerful new tool to characterize polymer brush coatings.
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Affiliation(s)
- Andres de Los Santos Pereira
- Department of Chemistry and Physics of Surfaces and Biointerfaces, Institute of Macromolecular Chemistry, Czech Academy of Sciences, Heyrovsky sq. 2, 162 06 Prague, Czech Republic
| | | | - Jan Svoboda
- Department of Chemistry and Physics of Surfaces and Biointerfaces, Institute of Macromolecular Chemistry, Czech Academy of Sciences, Heyrovsky sq. 2, 162 06 Prague, Czech Republic
| | - Radoslava Sivkova
- Department of Chemistry and Physics of Surfaces and Biointerfaces, Institute of Macromolecular Chemistry, Czech Academy of Sciences, Heyrovsky sq. 2, 162 06 Prague, Czech Republic
| | - Iryna Romanenko
- Department of Chemistry and Physics of Surfaces and Biointerfaces, Institute of Macromolecular Chemistry, Czech Academy of Sciences, Heyrovsky sq. 2, 162 06 Prague, Czech Republic
| | - Bogdana Bashta
- Department of Chemistry and Physics of Surfaces and Biointerfaces, Institute of Macromolecular Chemistry, Czech Academy of Sciences, Heyrovsky sq. 2, 162 06 Prague, Czech Republic
| | - Fritz Keilmann
- Fakultät für Physik & Center for NanoScience (CeNS), Ludwig-Maximilians-Universität, 80539 München, Germany
| | - Ognen Pop-Georgievski
- Department of Chemistry and Physics of Surfaces and Biointerfaces, Institute of Macromolecular Chemistry, Czech Academy of Sciences, Heyrovsky sq. 2, 162 06 Prague, Czech Republic
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11
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Zimmermann R, Duval JF, Werner C. On the analysis of ionic surface conduction to unravel charging processes at macroscopic soft and hard solid–liquid interfaces. Curr Opin Colloid Interface Sci 2019. [DOI: 10.1016/j.cocis.2019.10.004] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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12
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Pop-Georgievski O, Zimmermann R, Kotelnikov I, Proks V, Romeis D, Kučka J, Caspari A, Rypáček F, Werner C. Impact of Bioactive Peptide Motifs on Molecular Structure, Charging, and Nonfouling Properties of Poly(ethylene oxide) Brushes. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2018; 34:6010-6020. [PMID: 29728048 DOI: 10.1021/acs.langmuir.8b00441] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Polymer layers capable of suppressing protein adsorption from biological media while presenting extracellular matrix-derived peptide motifs offer valuable new options for biomimetic surface engineering. Herein, we provide detailed insights into physicochemical changes induced in a nonfouling poly(ethylene oxide) (PEO) brush/polydopamine (PDA) system by incorporation of adhesion ligand (RGD) peptides. Brushes with high surface chain densities (σ ≥ 0.5 chains·nm-2) and pronounced hydrophilicity (water contact angles ≤ 10°) were prepared by end-tethering of heterobifunctional PEOs ( Mn ≈ 20 000 g·mol-1) to PDA-modified surfaces from a reactive melt. Using alkyne distal end group on the PEO chains, azidopentanoic-bearing peptides were coupled through a copper-catalyzed Huisgen azide-alkyne "click" cycloaddition reaction. The surface concentration of RGD was tuned from complete saturation of the PEO surface with peptides (1.7 × 105 fmol·cm-2) to values which may induce distinct differences in cell adhesion (<6.0 × 102 fmol·cm-2). Infrared reflection-absorption and X-ray photoelectron spectroscopies proved the PDA-PEO layers covalent structure and the immobilization of RGD peptides. The complete reconstruction of experimental electrohydrodynamics data utilizing mean-field theory predictions further verified the attained brush structure of the end-tethered PEO chains which provided hydrodynamic screening of the PDA anchor. Increasing the surface concentration of immobilized RGD peptides led to increased interfacial charging. Supported by simulations, this observation was attributed to the ionization of functional groups in the amino acid sequence and to the pH-dependent adsorption of water ions (OH- > H3O+) from the electrolyte. Despite the distinct differences observed in the electrokinetic analysis of the surfaces bearing different amounts of RGD, it was found that the peptide presence on PEO(20 000)-PDA layers does not have a significant effect on the nonfouling properties of the system. Notably, the presented PEO(20 000)-PDA layers bearing RGD peptides in the surface concentration range 5.9 to 1.7 × 105 fmol·cm-2 reduced the protein adsorption from fetal bovine serum to less than 30 ng·cm-2, that is, values comparable to the ones obtained for pristine PEO(20 000)-PDA layers.
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Affiliation(s)
- Ognen Pop-Georgievski
- Institute of Macromolecular Chemistry , Czech Academy of Sciences , Heyrovskeho nam. 2 , 162 06 Prague 6 , Czech Republic
| | - Ralf Zimmermann
- Max Bergmann Center of Biomaterials Dresden , Leibniz Institute of Polymer Research Dresden , Hohe Str. 6 , 01069 Dresden , Germany
| | - Ilya Kotelnikov
- Institute of Macromolecular Chemistry , Czech Academy of Sciences , Heyrovskeho nam. 2 , 162 06 Prague 6 , Czech Republic
| | - Vladimir Proks
- Institute of Macromolecular Chemistry , Czech Academy of Sciences , Heyrovskeho nam. 2 , 162 06 Prague 6 , Czech Republic
| | - Dirk Romeis
- Max Bergmann Center of Biomaterials Dresden , Leibniz Institute of Polymer Research Dresden , Hohe Str. 6 , 01069 Dresden , Germany
| | - Jan Kučka
- Institute of Macromolecular Chemistry , Czech Academy of Sciences , Heyrovskeho nam. 2 , 162 06 Prague 6 , Czech Republic
| | - Anja Caspari
- Max Bergmann Center of Biomaterials Dresden , Leibniz Institute of Polymer Research Dresden , Hohe Str. 6 , 01069 Dresden , Germany
| | - František Rypáček
- Institute of Macromolecular Chemistry , Czech Academy of Sciences , Heyrovskeho nam. 2 , 162 06 Prague 6 , Czech Republic
| | - Carsten Werner
- Max Bergmann Center of Biomaterials Dresden , Leibniz Institute of Polymer Research Dresden , Hohe Str. 6 , 01069 Dresden , Germany
- Center of Regenerative Therapies Dresden , Technische Universität Dresden , Tatzberg 47 , 01167 Dresden , Germany
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13
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Beaussart A, Caillet C, Bihannic I, Zimmermann R, Duval JFL. Remarkable reversal of electrostatic interaction forces on zwitterionic soft nanointerfaces in a monovalent aqueous electrolyte: an AFM study at the single nanoparticle level. NANOSCALE 2018; 10:3181-3190. [PMID: 29372221 DOI: 10.1039/c7nr07976a] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Soft (nano)colloids are increasingly used in medical applications due to the versatile options they offer in terms of e.g. tunable chemical composition, adaptable physical properties and (bio)functionalization perspectives. Obtaining a clear understanding of the nature of the interaction forces that such particles experience with neighboring charged (bio)surfaces is a mandatory prerequisite to draw a comprehensive and mechanistic picture of their stability and reactivity and to further optimize their current functionalities. In this study, adopting an original strategy for nanoparticle attachment to atomic force microscopy (AFM) tips, we demonstrate that the sign of electrostatic forces between carboxylate-terminated poly(amidoamine) nanodendrimers (∼9 nm in diameter) and planar cysteamine-coated gold surfaces can be tailored under fixed pH conditions upon the sole variation of the monovalent salt concentration in solution. The origin of this unconventional electrostatic force reversal is deciphered upon confrontation between AFM force measurements and mean-field force evaluation performed beyond the Derjaguin approximation by integrating the dendrimer and cysteamine electrostatic properties derived independently from electrokinetic measurements. It is shown that the electrostatic force reversal (i) originates from the zwitterionic character of the nanodendrimer-solution interphase, and (ii) becomes operational under the strict condition that the sub-nanometric separation distance between peripheral carboxylate groups and intraparticulate amines is of the order of the characteristic electric Debye layer thickness. The possibility to mediate - via suitable adjustment of monovalent salt content in solution - both the magnitude and sign of the electrostatic forces acting on soft interfaces with zwitterionic functionality paves the way for the design of innovative strategies to control the stability of nanoparticles against aggregation, and to modulate their adhesion onto inorganic surfaces or living organisms.
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Affiliation(s)
- Audrey Beaussart
- CNRS, LIEC (Laboratoire Interdisciplinaire des Environnements Continentaux), UMR7360, Vandoeuvre-lès-Nancy F-54501, France
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14
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Marschelke C, Raguzin I, Matura A, Fery A, Synytska A. Controlled and tunable design of polymer interface for immobilization of enzymes: does curvature matter? SOFT MATTER 2017; 13:1074-1084. [PMID: 28094405 DOI: 10.1039/c6sm02380k] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Control and tuning of surface properties is indispensable for the programmed and rational design of materials. Particularly, polymeric brush-modified colloids can be used as carrier materials for enzyme immobilization. Although it is of prime importance to control the brush architecture, there is still a lack of systematic investigations concerning the impact of grafting density on the properties of the designed interface, as well as on the immobilization of biomolecules. In this work, we investigate the surface properties of polymer brushes with different grafting densities prepared using a "grafting from" approach on flat and on colloidal particle substrates by varying the density of initiator groups. In this way, we control and tune interfacial properties of the carrier material such as swelling, charge, adhesion as well as adsorption of laccase from Trametes versicolor on the grafted polyelectrolyte layer. We show that there is no direct transferability of the results received from planar to curved substrates regarding the swelling behavior in dependence on the grafting density. The maximum of swelling degree of PDMAEMA layers is achieved at 0.34 nm-2 and at 0.1 nm-2 grafting density for planar and curved particle substrates, respectively. The adhesion properties of the polymeric layer on both substrates are also strongly influenced by the grafting density, i.e. a decrease of the grafting density causes a transition from the adhesive to non-adhesive state. As proven by the cryo-TEM and AFM force distance measurements, an immobilization of laccase from Trametes versicolor causes a decrease of the polymer swelling and therefore leads to the changes in the surface morphology, charge and adhesion performance of final polymer-enzyme layer. Moreover, the higher effectiveness and activity of laccase were observed for the intermediate grafting densities which seem to be preferable over the maximum brush densities.
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Affiliation(s)
- Claudia Marschelke
- Leibniz Institute of Polymer Research Dresden, Hohe Str. 6, 01069, Dresden, Germany
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15
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Mahalik JP, Sumpter BG, Kumar R. Vertical Phase Segregation Induced by Dipolar Interactions in Planar Polymer Brushes. Macromolecules 2016. [DOI: 10.1021/acs.macromol.6b01138] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Affiliation(s)
- Jyoti P. Mahalik
- Computer
Science and Mathematics
Division and Center for Nanophase Materials
Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Bobby G. Sumpter
- Computer
Science and Mathematics
Division and Center for Nanophase Materials
Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Rajeev Kumar
- Computer
Science and Mathematics
Division and Center for Nanophase Materials
Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
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16
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Duval JF, Werner C, Zimmermann R. Electrokinetics of soft polymeric interphases with layered distribution of anionic and cationic charges. Curr Opin Colloid Interface Sci 2016. [DOI: 10.1016/j.cocis.2016.05.002] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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17
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Zimmermann R, Werner C, Duval JFL. Recent Progress and Perspectives in the Electrokinetic Characterization of Polyelectrolyte Films. Polymers (Basel) 2015; 8:polym8010007. [PMID: 30979104 PMCID: PMC6432592 DOI: 10.3390/polym8010007] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2015] [Revised: 12/22/2015] [Accepted: 12/23/2015] [Indexed: 11/16/2022] Open
Abstract
The analysis of the charge, structure and molecular interactions of/within polymeric substrates defines an important analytical challenge in materials science. Accordingly, advanced electrokinetic methods and theories have been developed to investigate the charging mechanisms and structure of soft material coatings. In particular, there has been significant progress in the quantitative interpretation of streaming current and surface conductivity data of polymeric films from the application of recent theories developed for the electrohydrodynamics of diffuse soft planar interfaces. Here, we review the theory and experimental strategies to analyze the interrelations of the charge and structure of polyelectrolyte layers supported by planar carriers under electrokinetic conditions. To illustrate the options arising from these developments, we discuss experimental and simulation data for plasma-immobilized poly(acrylic acid) films and for a polyelectrolyte bilayer consisting of poly(ethylene imine) and poly(acrylic acid). Finally, we briefly outline potential future developments in the field of the electrokinetics of polyelectrolyte layers.
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Affiliation(s)
- Ralf Zimmermann
- Leibniz Institute of Polymer Research Dresden, Max Bergmann Center of Biomaterials Dresden, Hohe Strasse 6, 01069 Dresden, Germany.
| | - Carsten Werner
- Leibniz Institute of Polymer Research Dresden, Max Bergmann Center of Biomaterials Dresden, Hohe Strasse 6, 01069 Dresden, Germany.
- Technische Universität Dresden, Center for Regenerative Therapies Dresden, Tatzberg 47, 01307 Dresden, Germany.
| | - Jérôme F L Duval
- Laboratoire Interdisciplinaire des Environnements Continentaux (LIEC), CNRS UMR 7360, 15 avenue du Charmois, B.P. 40, F-54501 Vandoeuvre-lès-Nancy cedex, France.
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Moussa M, Caillet C, Town RM, Duval JFL. Remarkable electrokinetic features of charge-stratified soft nanoparticles: mobility reversal in monovalent aqueous electrolyte. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2015; 31:5656-5666. [PMID: 25939023 DOI: 10.1021/acs.langmuir.5b01241] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
The electrokinetic behavior of G6.5 carboxylate-terminated poly(amidoamine) (PAMAM) starburst dendrimers (8 ± 1 nm diameter) is investigated over a broad range of pH values (3-9) and NaNO3 concentrations (c(∞ )= 2-200 mM). The dependence of nanodendrimer electrophoretic mobility μ on pH and c(∞) is marked by an unconventional decrease of the point of zero mobility (PZM) from 5.4 to 5.5 to 3.8 upon increase in salt concentration, with PZM defined as the pH value at which a reversal of the mobility sign is reached. The existence of a common intersection point is further evidenced for series of mobility versus pH curves measured at different NaNO3 concentrations. Using soft particle electrokinetic theory, this remarkable behavior is shown to originate from the zwitterionic functionality of the PAMAM-COOH particles. The dependence of PZM on c(∞) results from the coupling between electroosmotic flow and dendrimeric interphase defined by a nonuniform distribution of amine and carboxylic functional groups. In turn, μ reflects the sign and distribution of particle charges located within an electrokinetically active region, the dimension of which is determined by the Debye length, varied here in the range 0.7-6.8 nm. In agreement with theory, the electrokinetics of smaller G4.5 PAMAM-COOH nanoparticles (5 ± 0.5 nm diameter) further confirms that the PZM is shifted to higher pH with decreasing dendrimer size. Depending on pH, a mobility extremum is obtained under conditions where the Debye length and the particle radius are comparable. This results from changes in particle structure compactness following salt- and pH-mediated modulations of intraparticle Coulombic interactions. The findings solidly evidence the possible occurrence of particle mobility reversal in monovalent salt solution suggested by recent molecular dynamic simulations and anticipated from earlier mean-field electrokinetic theory.
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Affiliation(s)
- Mariam Moussa
- †LIEC (Laboratoire Interdisciplinaire des Environnements Continentaux), UMR7360, CNRS, Vandoeuvre-lès-Nancy F-54501, France
- ‡LIEC, UMR7360, Université de Lorraine, Vandoeuvre-lès-Nancy F-54501, France
| | - Céline Caillet
- †LIEC (Laboratoire Interdisciplinaire des Environnements Continentaux), UMR7360, CNRS, Vandoeuvre-lès-Nancy F-54501, France
- ‡LIEC, UMR7360, Université de Lorraine, Vandoeuvre-lès-Nancy F-54501, France
| | - Raewyn M Town
- §Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, Campusvej 55, 5230 Odense, Denmark
| | - Jérôme F L Duval
- †LIEC (Laboratoire Interdisciplinaire des Environnements Continentaux), UMR7360, CNRS, Vandoeuvre-lès-Nancy F-54501, France
- ‡LIEC, UMR7360, Université de Lorraine, Vandoeuvre-lès-Nancy F-54501, France
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