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Mella M, Tagliabue A, Mollica L, Vaghi S, Izzo L. Inducing pH control over the critical micelle concentration of zwitterionic surfactants via polyacids adsorption: Effect of chain length and structure. J Colloid Interface Sci 2022; 606:1636-1651. [PMID: 34500165 DOI: 10.1016/j.jcis.2021.07.076] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2021] [Revised: 07/12/2021] [Accepted: 07/13/2021] [Indexed: 10/20/2022]
Abstract
HYPOTHESIS The critical concentration above which micelles form from zwitterionic surfactant solutions and their thermodynamic stability is affected by the interaction with weak Brønsted polyacid chains (An) via the formation of charged hydrogen bonds between the latter and anionic moieties. EXPERIMENTS The interaction between zwitterionic micelles and polyacids capable of forming hydrogen bonds, and its dependence on the environmental pH and polymer structure, has been studied with constant-pH simulations and a restricted primitive model for all electrolytes. FINDINGS At low pH, the formation of polyacid/micelle complexes is witnessed independently of the polymer size or structure, so that the concentration above which micelles form is substantially decreased compared to polyacid-free cases. Upon rising pH, polymer desorption takes place within a narrow range of pH values, its location markedly depending on the size and structure of polyacids, and on the relative disposition between headgroup charged moieties. Thus, the desorption onset for long linear polyacids (A60) interacting with sulphobetainic headgroups is roughly two pH units higher than for six decameric chains (6A10) adsorbed onto micelles bearing phosphorylcholinic headgroups. This effect, together with the preferential desorption of chain ends at intermediate pH, may be exploited for drug delivery purposes or building advanced metamaterials.
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Affiliation(s)
- Massimo Mella
- Dipartimento di Scienza ed Alta Tecnologia, Università degli Studi dell'Insubria, via Valleggio 9, 22100 Como, Italy.
| | - Andrea Tagliabue
- Dipartimento di Scienza ed Alta Tecnologia, Università degli Studi dell'Insubria, via Valleggio 9, 22100 Como, Italy
| | - Luca Mollica
- Dipartimento di Biotecnologie Mediche e Medicina Traslazionale, Università degli Studi di Milano, via Vanvitelli 32, 20133 Milano, Italy
| | - Stefano Vaghi
- Dipartimento di Scienza ed Alta Tecnologia, Università degli Studi dell'Insubria, via Valleggio 9, 22100 Como, Italy
| | - Lorella Izzo
- Dipartimento di Biotecnologie e Scienze della Vita, Universitá degli Studi dell'Insubria, via J. H. Dunant 3, 21100 Varese, Italy
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2
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Caetano DLZ, Metzler R, Cherstvy AG, de Carvalho SJ. Adsorption of lysozyme into a charged confining pore. Phys Chem Chem Phys 2021; 23:27195-27206. [PMID: 34821240 DOI: 10.1039/d1cp03185f] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Several applications arise from the confinement of proteins on surfaces because their stability and biological activity are enhanced. It is also known that the way in which a protein adsorbs on the surface is important for its biological function since its active sites should not be obstructed. In this study, the adsorption properties of hen egg-white lysozyme, HEWL, into a negatively charged silica pore is examined by employing a coarse-grained model and constant-pH Monte Carlo simulations. The role of electrostatic interactions is taken into account via including the Debye-Hückel potentials into the Cα structure-based model. We evaluate the effects of pH, salt concentration, and pore radius on the protein preferential orientation and spatial distribution of its residues regarding the pore surface. By mapping the residues that stay closer to the pore surface, we find that the increase of pH leads to orientational changes of the adsorbed protein when the solution pH gets closer to the HEWL isoelectric point. Under these conditions, the pKa shift of these important residues caused by the adsorption into the charged confining surface results in a HEWL charge distribution that stabilizes the adsorption in the observed protein orientation. We compare our observations to the results of the pKa shift for HEWL available in the literature and to some experimental data.
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Affiliation(s)
- Daniel L Z Caetano
- Institute of Chemistry, State University of Campinas (UNICAMP), Campinas, Brazil.,Center for Computational Engineering and Sciences, State University of Campinas (UNICAMP), Campinas, Brazil
| | - Ralf Metzler
- Institute for Physics & Astronomy, University of Potsdam, 14476 Potsdam-Golm, Germany
| | - Andrey G Cherstvy
- Institute for Physics & Astronomy, University of Potsdam, 14476 Potsdam-Golm, Germany.,Institut für Physik, Humboldt-Universität zu Berlin, 12489 Berlin, Germany
| | - Sidney J de Carvalho
- Department of Physics, São Paulo State University (UNESP), Institute of Biosciences, Humanities and Exact Sciences, São José do Rio Preto, Brazil.
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3
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Affiliation(s)
- Qiuhui Chang
- Beijing National Laboratory for Molecular Sciences, State Key Laboratory of Polymer Physics and Chemistry, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China
- University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Jian Jiang
- Beijing National Laboratory for Molecular Sciences, State Key Laboratory of Polymer Physics and Chemistry, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China
- University of Chinese Academy of Sciences, Beijing 100049, P. R. China
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4
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Jiang J. Non-monotonic Effects of Intrinsic Stiffness and Concentration of Polyelectrolytes on the Electro-Sorption. Macromolecules 2021. [DOI: 10.1021/acs.macromol.0c02472] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Jian Jiang
- Beijing National Laboratory for Molecular Sciences, State Key Laboratory of Polymer Physics and Chemistry, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China
- University of Chinese Academy of Sciences, Beijing 100049, P. R. China
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5
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Mella M, Tagliabue A, Izzo L. On the distribution of hydrophilic polyelectrolytes and their counterions around zwitterionic micelles: the possible impact on the charge density in solution. SOFT MATTER 2021; 17:1267-1283. [PMID: 33300543 DOI: 10.1039/d0sm01541e] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Despite their charge neutrality, micelles composed of surfactants with zwitterionic headgroups selectively accumulate anions at their hydrophobic core/solution interphase due to electrostatic interactions if headgroup positive moieties are the innermost. This tendency may be markedly enhanced if polyions substitute simple ions. To investigate this possibility, solutions composed of zwitterionic micelles and hydrophilic polyanions have been investigated with Monte Carlo simulations representing the studied systems via primitive electrolyte models. Structural and energetic properties are obtained to highlight the impact of connecting simple ions into polyions on the interactions between electrolytes and micelles. Despite the latter, polyanions conserve their conformational properties. A marked increase in the concentration of charged species inside the micellar corona is, instead, found when polyions are present independently of their charge sign or the headgroup structure. Thus, polyelectrolytes act as "shuttle" for all charged species, with the potential of increasing reactions rates involving the latter due to mass effects. Besides, results for the polyions/micelles mixing free energy and Helmholtz energy profiles indicate that the critical micelle concentration is impacted minimally by hydrophilic polyelectrolytes, an outcome agreeing with experiments. This finding is entirely due to weak enthalpic effects while mixing hydrophilic polyions and micelles. A strong reduction in the screening of the micelle negative charge, acquired following the adsorption of anions in the corona and due to counterions layering just outside it (the so called "chameleon effect"), is forecasted when polyanions substitute monovalent anions.
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Affiliation(s)
- Massimo Mella
- Dipartimento di Scienza ed Alta Tecnologia, Università degli Studi dell'Insubria, via Valleggio 11, 22100, Como, Italy.
| | - Andrea Tagliabue
- Dipartimento di Scienza ed Alta Tecnologia, Università degli Studi dell'Insubria, via Valleggio 11, 22100, Como, Italy.
| | - Lorella Izzo
- Dipartimento di Biotecnologie e Scienze della Vita, Università degli Studi dell'Insubria, via J. H. Dunant 3, 21100, Varese, Italy
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6
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Wang T, Wang S, Tong C. Charge reversal in the collapse of polyelectrolyte star brushes under an electric field. Chem Phys 2020. [DOI: 10.1016/j.chemphys.2020.110810] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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Caetano DLZ, de Carvalho SJ, Metzler R, Cherstvy AG. Critical adsorption of multiple polyelectrolytes onto a nanosphere: splitting the adsorption-desorption transition boundary. J R Soc Interface 2020; 17:20200199. [PMID: 32574545 PMCID: PMC7328387 DOI: 10.1098/rsif.2020.0199] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2020] [Accepted: 06/03/2020] [Indexed: 01/09/2023] Open
Abstract
Employing extensive Monte Carlo computer simulations, we investigate in detail the properties of multichain adsorption of charged flexible polyelectrolytes (PEs) onto oppositely charged spherical nanoparticles (SNPs). We quantify the conditions of critical adsorption-the phase-separation curve between the adsorbed and desorbed states of the PEs-as a function of the SNP surface-charge density and the concentration of added salt. We study the degree of fluctuations of the PE-SNP electrostatic binding energy, which we use to quantify the emergence of the phase subtransitions, including a series of partially adsorbed PE configurations. We demonstrate how the phase-separation adsorption-desorption boundary shifts and splits into multiple subtransitions at low-salt conditions, thereby generalizing and extending the results for critical adsorption of a single PE onto the SNP. The current findings are relevant for finite concentrations of PEs around the attracting SNP, such as the conditions for PE adsorption onto globular proteins carrying opposite electric charges.
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Affiliation(s)
- Daniel L. Z. Caetano
- São Paulo State University (UNESP), Institute of Biosciences, Humanities and Exact Sciences, Campus São José do Rio Preto, 15054-000 Brazil
- Institute of Chemistry, State University of Campinas (UNICAMP), 13083-970 Campinas, Brazil
- Center for Computational Engineering and Sciences, State University of Campinas (UNICAMP), 13083-970 Campinas, Brazil
| | - Sidney J. de Carvalho
- São Paulo State University (UNESP), Institute of Biosciences, Humanities and Exact Sciences, Campus São José do Rio Preto, 15054-000 Brazil
| | - Ralf Metzler
- Institute for Physics and Astronomy, University of Potsdam, 14476 Potsdam-Golm, Germany
| | - Andrey G. Cherstvy
- Institute for Physics and Astronomy, University of Potsdam, 14476 Potsdam-Golm, Germany
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8
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Mella M, Tagliabue A, Mollica L, Izzo L. Monte Carlo study of the effects of macroion charge distribution on the ionization and adsorption of weak polyelectrolytes and concurrent counterion release. J Colloid Interface Sci 2020; 560:667-680. [PMID: 31704002 DOI: 10.1016/j.jcis.2019.10.051] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2019] [Revised: 10/12/2019] [Accepted: 10/14/2019] [Indexed: 01/16/2023]
Abstract
HYPOTHESIS Adsorption of weak polyelectrolytes onto charged nanoparticles, and concurrent effects such as spatial partitioning of ions may be influenced by details of the polyelectrolyte structure (linear or star-like) and size, by the mobility of the nanoparticle surface charge, or the valence of the nanoparticle counterions. EXPERIMENTS Ionization and complexation of weak polyelectrolytes on spherical macroions with monovalent and divalent countrions has been studied with constant-pH Monte Carlo titrations and primitive electrolyte models for linear and star-like polymers capable, also, of forming charged hydrogen bonds. Nanoparticles surface charge has been represented either as a single colloid-centered total charge (CCTC) or as surface-tethered mobile monovalent spherical charges (SMMSC). FINDINGS Differences in the average number of adsorbed polyelectrolyte arms and their average charge, and in the relative amount of macroion counterions (m-CI's) released upon polymer adsorption are found between CCTC and SMMSC nanoparticles. The amount of the counterions released also depends on the polymer structure. As CCTC adsorbs a lower number of star-like species arms, the degree of condensation of polymer counterions (p-CI's) onto the polyelectrolyte is also substantially higher for the CCTC colloid, with a concurrent decrease of the osmotic coefficient values.
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Affiliation(s)
- Massimo Mella
- Dipartimento di Scienza ed Alta Tecnologia, Università degli Studi dell'Insubria, via Valleggio 11, 22100 Como, Italy.
| | - Andrea Tagliabue
- Dipartimento di Scienza ed Alta Tecnologia, Università degli Studi dell'Insubria, via Valleggio 11, 22100 Como, Italy
| | - Luca Mollica
- Dipartimento di Biotecnologie Mediche e Medicina Traslazionale, Università degli Studi di Milano, via Vanvitelli 32, 20133 Milano, Italy; Istituto Nazionale Genetica Molecolare "Romeo ed Enrica Invernizzi", Via F. Sforza 35, 20122 Milano, Italy
| | - Lorella Izzo
- Dipartimento di Biotecnologie e Scienze della Vita, Università degli Studi dell'Insubria, via J. H. Dunant 3, 21100 Varese, Italy.
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9
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Morrin GT, Kienle DF, Schwartz DK. Standalone interferometry-based calibration of convex lens-induced confinement microscopy with nanoscale accuracy. Analyst 2019; 144:2628-2634. [PMID: 30839956 PMCID: PMC6779313 DOI: 10.1039/c8an02300j] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Strongly confined environments (confined dimensions between 1-100 nm) represent unique challenges and opportunities for understanding and manipulating molecular behavior due to the significant effects of electric double layers, high surface-area to volume ratios, and other phenomena at the nanoscale. Convex Lens-induced Confinement (CLiC) can be used to analyze the dynamics of individual molecules or particles confined in a planar slit geometry with continuously varying gap thickness. We describe an interferometry-based method for precise measurement of the slit pore geometry. Specifically, this approach permitted accurate characterization of separation distances as small as 5 nm, with 1 nm precision, without a priori knowledge or assumptions about the contact geometry, as well as a greatly simplified experimental setup that required only a lens, coverslip, and inverted microscope. The interferometry-based measurement of gap height offered a distinct advantage over conventional fluorescent dye-based methods; e.g., accurate interferometric height measurements were made at low gap heights regardless of solution conditions, while the concentration of fluorescent dye was significantly impacted by solution conditions such as ionic strength or pH. The accuracy of the interferometric measurements was demonstrated by comparing the experimentally measured concentration of a charged fluorescent dye as a function of gap thickness with dye concentration profiles calculated using Debye-Hückel theory. Accurate characterization of nanoscale gap thickness will enable researchers to study a variety of practical and biologically relevant systems within the CLiC geometry.
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Affiliation(s)
- Gregory T Morrin
- Department of Chemical and Biological Engineering, University of Colorado Boulder, Boulder, CO 80309, USA.
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10
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Tagliabue A, Izzo L, Mella M. Absorbed weak polyelectrolytes: Impact of confinement, topology, and chemically specific interactions on ionization, conformation free energy, counterion condensation, and absorption equilibrium. ACTA ACUST UNITED AC 2019. [DOI: 10.1002/polb.24806] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Affiliation(s)
- Andrea Tagliabue
- Dipartimento di Scienza ed Alta TecnologiaUniversità degli Studi dell'Insubria via Valleggio 9, 22100, Como Italy
| | - Lorella Izzo
- Dipartimento di Biotecnologie e Scienze della VitaUniversità degli Studi dell'Insubria via J. H. Dunant 3, 21100, Varese Italy
| | - Massimo Mella
- Dipartimento di Scienza ed Alta TecnologiaUniversità degli Studi dell'Insubria via Valleggio 9, 22100, Como Italy
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11
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Affiliation(s)
- W. Nowicki
- Faculty of Chemistry, Adam Mickiewicz University, Umultowska 89b, 61-614 Poznań, Poland
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12
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Shojaei HR, Muthukumar M. Adsorption and encapsulation of flexible polyelectrolytes in charged spherical vesicles. J Chem Phys 2018; 146:244901. [PMID: 28668020 DOI: 10.1063/1.4986961] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We present a theory of adsorption of flexible polyelectrolytes on the interior and exterior surfaces of a charged vesicle in an electrolyte solution. The criteria for adsorption and the density profiles of the adsorbed polymer chain are derived in terms of various characteristics of the polymer, vesicle, and medium, such as the charge density and length of the polymer, charge density and size of the vesicle, electrolyte concentration and dielectric constant of the medium. For adsorption inside the vesicle, the competition between the loss of conformational entropy and gain in adsorption energy results in two kinds of encapsulated states, depending on the strength of the polymer-vesicle interaction. By considering also the adsorption from outside the vesicle, we derive the entropic and energy contributions to the free energy change to transfer an adsorbed chain in the interior to an adsorbed chain on the exterior. In this paper, we have used the Wentzel-Kramers-Brillouin (WKB) method to solve the equation for the probability distribution function of the chain. The present WKB results are compared with the previous results based on variational methods. The WKB and variational results are in good agreement for both the interior and exterior states of adsorption, except in the zero-salt limit for adsorption in the exterior region. The adsorption criteria and density profiles for both the interior and exterior states are presented in terms of various experimentally controllable variables. Calculation of the dependencies of free energy change to transfer an adsorbed chain from the interior to the exterior surface on salt concentration and vesicle radius shows that the free energy penalty to expel a chain from a vesicle is only of the order of thermal energy.
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Affiliation(s)
- H R Shojaei
- Department of Polymer Science and Engineering, University of Massachusetts, Amherst, Massachusetts 01003, USA
| | - M Muthukumar
- Department of Polymer Science and Engineering, University of Massachusetts, Amherst, Massachusetts 01003, USA
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13
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Caetano DLZ, de Carvalho SJ, Metzler R, Cherstvy AG. Critical adsorption of periodic and random polyampholytes onto charged surfaces. Phys Chem Chem Phys 2017; 19:23397-23413. [PMID: 28825753 DOI: 10.1039/c7cp04040g] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
How different are the properties of critical adsorption of polyampholytes and polyelectrolytes onto charged surfaces? How important are the details of polyampholyte charge distribution on the onset of critical adsorption transition? What are the scaling relations governing the dependence of critical surface charge density on salt concentration in the surrounding solution? Here, we employ Metropolis Monte Carlo simulations and uncover the scaling relations for critical adsorption for quenched periodic and random charge distributions along the polyampholyte chains. We also evaluate and discuss the dependence of the adsorbed layer width on solution salinity and details of the charge distribution. We contrast our findings to the known results for polyelectrolyte adsorption onto oppositely charged surfaces, in particular, their dependence on electrolyte concentration.
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Affiliation(s)
- Daniel L Z Caetano
- Sao Paulo State University (UNESP), Institute of Biosciences, Humanities and Exact Sciences (Ibilce), Campus Sao Jose do Rio Preto, 15054-000, Brazil.
| | - Sidney J de Carvalho
- Sao Paulo State University (UNESP), Institute of Biosciences, Humanities and Exact Sciences (Ibilce), Campus Sao Jose do Rio Preto, 15054-000, Brazil.
| | - Ralf Metzler
- Institute for Physics & Astronomy, University of Potsdam, 14476 Potsdam-Golm, Germany.
| | - Andrey G Cherstvy
- Institute for Physics & Astronomy, University of Potsdam, 14476 Potsdam-Golm, Germany.
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14
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Mella M, Izzo L. Modulation of ionization and structural properties of weak polyelectrolytes due to 1D, 2D, and 3D confinement. ACTA ACUST UNITED AC 2017. [DOI: 10.1002/polb.24351] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Affiliation(s)
- Massimo Mella
- Dipartimento di Scienza ed Alta Tecnologia; Università degli Studi dell'Insubria; via Valleggio 9 Como 22100 Italy
| | - Lorella Izzo
- Dipartimento di Chimica e Biologia; Università degli Studi di Salerno; via Giovanni Paolo II, 132 Fisciano 84084 Italy
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15
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de Carvalho SJ, Metzler R, Cherstvy AG. Inverted critical adsorption of polyelectrolytes in confinement. SOFT MATTER 2015; 11:4430-4443. [PMID: 25940939 DOI: 10.1039/c5sm00635j] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
What are the fundamental laws for the adsorption of charged polymers onto oppositely charged surfaces, for convex, planar, and concave geometries? This question is at the heart of surface coating applications, various complex formation phenomena, as well as in the context of cellular and viral biophysics. It has been a long-standing challenge in theoretical polymer physics; for realistic systems the quantitative understanding is however often achievable only by computer simulations. In this study, we present the findings of such extensive Monte-Carlo in silico experiments for polymer-surface adsorption in confined domains. We study the inverted critical adsorption of finite-length polyelectrolytes in three fundamental geometries: planar slit, cylindrical pore, and spherical cavity. The scaling relations extracted from simulations for the critical surface charge density σc-defining the adsorption-desorption transition-are in excellent agreement with our analytical calculations based on the ground-state analysis of the Edwards equation. In particular, we confirm the magnitude and scaling of σc for the concave interfaces versus the Debye screening length 1/κ and the extent of confinement a for these three interfaces for small κa values. For large κa the critical adsorption condition approaches the known planar limit. The transition between the two regimes takes place when the radius of surface curvature or half of the slit thickness a is of the order of 1/κ. We also rationalize how σc(κ) dependence gets modified for semi-flexible versus flexible chains under external confinement. We examine the implications of the chain length for critical adsorption-the effect often hard to tackle theoretically-putting an emphasis on polymers inside attractive spherical cavities. The applications of our findings to some biological systems are discussed, for instance the adsorption of nucleic acids onto the inner surfaces of cylindrical and spherical viral capsids.
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Affiliation(s)
- Sidney J de Carvalho
- Institute of Biosciences, Letters and Exact Sciences, Sao Paulo State University, 15054-000 Sao Jose do Rio Preto, Brazil.
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16
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Shin J, Cherstvy AG, Metzler R. Polymer Looping Is Controlled by Macromolecular Crowding, Spatial Confinement, and Chain Stiffness. ACS Macro Lett 2015; 4:202-206. [PMID: 35596432 DOI: 10.1021/mz500709w] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
We study by extensive computer simulations the looping characteristics of linear polymers with varying persistence length inside a spherical cavity in the presence of macromolecular crowding. For stiff chains, the looping probability and looping time reveal wildly oscillating patterns as functions of the chain length. The effects of crowding differ dramatically for flexible versus stiff polymers. While for flexible chains the looping kinetics is slowed down by the crowders, for stiffer chains the kinetics turns out to be either decreased or facilitated, depending on the polymer length. For severe confinement, the looping kinetics may become strongly facilitated by crowding. Our findings are of broad impact for DNA looping in the crowded and compartmentalized interior of living biological cells.
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Affiliation(s)
- Jaeoh Shin
- Institute
for Physics and Astronomy, University of Potsdam, 14476 Potsdam-Golm, Germany
- Max-Planck Institute
for the Physics of Complex Systems, 01187 Dresden, Germany
| | - Andrey G. Cherstvy
- Institute
for Physics and Astronomy, University of Potsdam, 14476 Potsdam-Golm, Germany
| | - Ralf Metzler
- Institute
for Physics and Astronomy, University of Potsdam, 14476 Potsdam-Golm, Germany
- Department
of Physics, Tampere University of Technology, 33101 Tampere, Finland
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17
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Suh D, Yasuoka K, Zeng XC. Molecular dynamics simulation of heterogeneous nucleation on nanotubes. RSC Adv 2015. [DOI: 10.1039/c5ra04398k] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Condensation rate inside and outside the tube depends on the pore diameter and length.
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Affiliation(s)
- Donguk Suh
- Department of Mechanical Engineering
- Keio University
- Yokohama, Japan
| | - Kenji Yasuoka
- Department of Mechanical Engineering
- Keio University
- Yokohama, Japan
| | - Xiao Cheng Zeng
- Department of Chemistry
- University of Nebraska-Lincoln
- Lincoln, USA
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18
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de Carvalho SJ, Metzler R, Cherstvy AG. Critical adsorption of polyelectrolytes onto charged Janus nanospheres. Phys Chem Chem Phys 2014; 16:15539-50. [DOI: 10.1039/c4cp02207f] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The conditions of critical polyelectrolyte adsorption onto spherical charged Janus nano-particles are exploited by Monte-Carlo computer simulations and theoretically.
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Affiliation(s)
| | - Ralf Metzler
- Institute for Physics and Astronomy
- University of Potsdam
- Potsdam-Golm, Germany
- Department of Physics
- Tampere University of Technology
| | - Andrey G. Cherstvy
- Institute for Physics and Astronomy
- University of Potsdam
- Potsdam-Golm, Germany
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19
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Tong C. The numerical study of the adsorption of flexible polyelectrolytes with the annealed charge distribution onto an oppositely charged sphere by the self-consistent field theory. J Chem Phys 2013; 139:084903. [DOI: 10.1063/1.4819037] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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20
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Kampmann TA, Boltz HH, Kierfeld J. Controlling adsorption of semiflexible polymers on planar and curved substrates. J Chem Phys 2013; 139:034903. [DOI: 10.1063/1.4813021] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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21
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Nunes SCC, Pinto P, Pais AACC. Nonrandom adsorption of polyelectrolyte chains on finite regularly charged surfaces. J Comput Chem 2013; 34:1198-209. [PMID: 23386422 DOI: 10.1002/jcc.23238] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2012] [Revised: 12/20/2012] [Accepted: 12/24/2012] [Indexed: 01/09/2023]
Abstract
Adsorption phenomena are relevant in a wide variety of subjects, from biophysics to technological applications. Different aspects, such as molecular recognition, multilayer deposition, and dynamics of polymer adsorption have been addressed. The methodologies used range from analytical and numerical methods to molecular dynamics or Monte Carlo simulations. In this work, a coarse-grained model is used to explore the adsorption of charged backbones to oppositely charged regions of a surface. These regions encompass those small enough to prevent complete adsorption, but extend to surfaces sufficiently large to promote adsorption with minimal effect on the three-dimensional conformation in bulk. Apart from the different surface areas explored, variations on the surface charge density, polyelectrolyte chain length, and chain stiffness were also considered. The degree of compaction of the polyelectrolyte, on adsorption, is different from that found in the bulk. Also, results indicate an nonuniform adsorption pattern on regularly charged surfaces.
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Affiliation(s)
- Sandra C C Nunes
- Department of Chemistry, University of Coimbra, Rua Larga 3004-535, Coimbra, Portugal
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Strong and Weak Polyelectrolyte Adsorption onto Oppositely Charged Curved Surfaces. POLYELECTROLYTE COMPLEXES IN THE DISPERSED AND SOLID STATE I 2013. [DOI: 10.1007/12_2012_183] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
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Tong C. The interplay of the polyelectrolyte-surface electrostatic and non-electrostatic interactions in the polyelectrolytes adsorption onto two charged objects – A self-consistent field study. J Chem Phys 2012; 137:104904. [DOI: 10.1063/1.4748815] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Cherstvy AG, Winkler RG. Polyelectrolyte adsorption onto oppositely charged interfaces: image-charge repulsion and surface curvature. J Phys Chem B 2012; 116:9838-45. [PMID: 22794191 DOI: 10.1021/jp304980e] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
We analyze theoretically the influence of low-dielectric boundaries on the adsorption of flexible polyelectrolytes onto planar and spherical oppositely charged surfaces in electrolyte solutions. We rationalize to what extent polymer chains are depleted from adsorbing interfaces by repulsive image forces. We employ the WKB (Wentzel-Kramers-Brillouin) quantum mechanical method for the Green function of the Edwards equation to determine the adsorption equilibrium. Scaling relations are determined for the critical adsorption strength required to initiate polymer adsorption onto these low-dielectric supports. Image-force repulsion shifts the equilibrium toward the desorbed state, demanding larger surface charge densities and polyelectrolyte linear charge densities for the adsorption to take place. The effect is particularly pronounced for a planar interface in a low-salt regime, where a dramatic change in the scaling behavior for the adsorption-desorption transition is predicted. For the adsorbed state, polymers with higher charge densities are displaced further from the interface by image-charge repulsions. We discuss relevant experimental evidence and argue about possible biological applications of the results.
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Affiliation(s)
- A G Cherstvy
- Institute for Physics and Astronomy, University of Potsdam, 14476 Potsdam-Golm, Germany.
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