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Akdeniz B, Wood JA, Lammertink RGH. Diffusiophoretic Behavior of Polyelectrolyte-Coated Particles. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2024; 40:5934-5944. [PMID: 38451220 PMCID: PMC10956496 DOI: 10.1021/acs.langmuir.3c03916] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2023] [Revised: 02/21/2024] [Accepted: 02/23/2024] [Indexed: 03/08/2024]
Abstract
Diffusiophoresis, the movement of particles under a solute concentration gradient, has practical implications in a number of applications, such as particle sorting, focusing, and sensing. For diffusiophoresis in an electrolyte solution, the particle velocity is described by the electrolyte relative concentration gradient and the diffusiophoretic mobility of the particle. The electrolyte concentration, which typically varies throughout the system in space and time, can also influence the zeta potential of particles in space and time. This variation affects the diffusiophoretic behavior, especially when the zeta potential is highly dependent on the electrolyte concentration. In this work, we show that adsorbing a single bilayer (or 4 bilayers) of a polyelectrolyte pair (PDADMAC/PSS) on the surface of microparticles resulted in effectively constant zeta potential values with respect to salt concentration throughout the experimental range of salt concentrations. This allowed a constant potential model for diffusiophoretic transport to describe the experimental observations, which was not the case for uncoated particles in the same electrolyte system. This work highlights the use of simple polyelectrolyte pairs to tune the zeta potential and maintain constant values for precise control of diffusiophoretic transport.
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Affiliation(s)
- Burak Akdeniz
- Soft Matter, Fluidics and Interfaces,
MESA+ Institute for Nanotechnology, University
of Twente, P.O. Box 217, Enschede 7500 AE, The Netherlands
| | - Jeffery A. Wood
- Soft Matter, Fluidics and Interfaces,
MESA+ Institute for Nanotechnology, University
of Twente, P.O. Box 217, Enschede 7500 AE, The Netherlands
| | - Rob G. H. Lammertink
- Soft Matter, Fluidics and Interfaces,
MESA+ Institute for Nanotechnology, University
of Twente, P.O. Box 217, Enschede 7500 AE, The Netherlands
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2
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Akdeniz B, Wood JA, Lammertink RGH. Diffusiophoresis and Diffusio-osmosis into a Dead-End Channel: Role of the Concentration-Dependence of Zeta Potential. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2023; 39:2322-2332. [PMID: 36708332 PMCID: PMC9933534 DOI: 10.1021/acs.langmuir.2c03000] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/02/2022] [Revised: 01/13/2023] [Indexed: 06/18/2023]
Abstract
Chemically induced transport methods open up new opportunities for colloidal transport in dead-end channel geometries. Diffusiophoresis, which describes particle movement under an electrolyte concentration gradient, has previously been demonstrated in dead-end channels. The presence of solute concentration gradients in such channels induces particle motion (phoresis) and fluid flow along solid walls (osmosis). The particle velocity inside a dead-end channel is thus influenced by particle diffusiophoresis and wall diffusio-osmosis. The magnitude of phoresis and osmosis depends on the solute's relative concentration gradient, the electrokinetic parameters of the particle and the wall, and the diffusivity contrast of cations and anions. Although it is known that some of those parameters are affected by electrolyte concentration, e.g., zeta potential, research to date often interprets results using averaged and constant zeta potential values. In this work, we demonstrate that concentration-dependent zeta potentials are essential when the zeta potential strongly depends on electrolyte concentration for correctly describing the particle transport inside dead-end channels. Simulations including concentration-dependent zeta potentials for the particle and wall matched with experimental observations, whereas simulations using constant, averaged zeta potentials failed to capture particle dynamics. These results contribute to the fundamental understanding of diffusiophoresis and the diffusio-osmosis process.
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Lee S, Lee J, Ault JT. The role of variable zeta potential on diffusiophoretic and diffusioosmotic transport. Colloids Surf A Physicochem Eng Asp 2023. [DOI: 10.1016/j.colsurfa.2022.130775] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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Keh HJ. Diffusiophoresis of charged particles and diffusioosmosis of electrolyte solutions. Curr Opin Colloid Interface Sci 2016. [DOI: 10.1016/j.cocis.2016.05.008] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Li WC, Keh HJ. Diffusiophoretic mobility of charge-regulating porous particles. Electrophoresis 2016; 37:2139-46. [DOI: 10.1002/elps.201600091] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2016] [Revised: 04/02/2016] [Accepted: 05/07/2016] [Indexed: 11/09/2022]
Affiliation(s)
- Wei C. Li
- Department of Chemical Engineering; National Taiwan University; Taipei Taiwan
| | - Huan J. Keh
- Department of Chemical Engineering; National Taiwan University; Taipei Taiwan
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Fang W, Lee E. Diffusiophoretic motion of an isolated charged porous sphere. J Colloid Interface Sci 2015; 459:273-283. [DOI: 10.1016/j.jcis.2015.08.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2015] [Accepted: 08/01/2015] [Indexed: 10/23/2022]
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Mei L, Chou TH, Cheng YS, Huang MJ, Yeh LH, Qian S. Electrophoresis of pH-regulated nanoparticles: impact of the Stern layer. Phys Chem Chem Phys 2015; 18:9927-34. [PMID: 26509958 DOI: 10.1039/c5cp05728k] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
A multi-ion model taking into account the Stern layer effect and the surface chemistry reactions is developed for the first time to investigate the surface charge properties and electrophoresis of pH-regulated silica nanoparticles (NPs). The applicability of the model is validated by comparing its prediction to the experimental data of the electrophoretic mobility of silica NPs available from the literature. Results show that if the particle size is fixed, the Stern layer effect on the surface charge properties of the NP is notable at high pH and background salt concentration; however, that effect on the particle mobility is significant when pH is around neutrality and the salt concentration is medium high (ca. 0.07 M) because of the double-layer polarization effect. Moreover, if pH and the background salt concentration are fixed, the Stern layer effect on the zeta potential and electrophoretic mobility of the NP becomes more significant for smaller particle size. Neglecting the Stern layer effect could result in the overestimation of the zeta potential, surface charge density, and electrophoretic mobility of a NP on the order of several times.
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Affiliation(s)
- Lanju Mei
- Institute of Micro/Nanotechnology, Old Dominion University, Norfolk, VA 23529, USA.
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9
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Electrophoretic mobility and electric conductivity in suspensions of charge-regulating porous particles. Colloid Polym Sci 2015. [DOI: 10.1007/s00396-015-3580-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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10
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Huang HY, Keh HJ. Diffusiophoresis in Suspensions of Charged Porous Particles. J Phys Chem B 2015; 119:2040-50. [DOI: 10.1021/jp510448x] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Hsin Y. Huang
- Department of Chemical Engineering, National Taiwan University, Taipei 10617, Taiwan, Republic of China
| | - Huan J. Keh
- Department of Chemical Engineering, National Taiwan University, Taipei 10617, Taiwan, Republic of China
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11
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Tseng S, Chung YC, Hsu JP. Diffusiophoresis of a soft, pH-regulated particle in a solution containing multiple ionic species. J Colloid Interface Sci 2015; 438:196-203. [DOI: 10.1016/j.jcis.2014.09.069] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2014] [Revised: 09/24/2014] [Accepted: 09/25/2014] [Indexed: 11/24/2022]
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12
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Sedimentation velocity and potential in a concentrated suspension of charged soft spheres. Colloids Surf A Physicochem Eng Asp 2014. [DOI: 10.1016/j.colsurfa.2012.08.069] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Abstract
AbstractProteins and other biomolecules contain acidic and basic titratable groups that give rise to intricate charge distributions and control electrostatic interactions. ‘Charge regulation’ concerns how the proton equilibria of these sites are perturbed when approached by alien molecular matter such as other proteins, surfaces and membranes, DNA, polyelectrolytes etc. Importantly, this perturbation generates a charge response that leads to attractive intermolecular interactions that can be conveniently described by a single molecular property – the charge capacitance. The capacitance quantifies molecular charge fluctuations, i.e. it is the variance of the mean charge and is an intrinsic property on par with the net charge and the dipole moment. It directly enters the free energy expression for intermolecular interactions and can be obtained experimentally from the derivative of the titration curve or theoretically from simulations. In this review, we focus on the capacitance concept as a predictive parameter for charge regulation and demonstrate how it can be used to estimate the interaction of a protein with other proteins, polyelectrolytes, membranes as well as with ligands.
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Tseng S, Hsieh TH, Yeh LH, Wang N, Hsu JP. Electrophoresis of a charge-regulated soft sphere: Importance of effective membrane charge. Colloids Surf B Biointerfaces 2013; 102:864-70. [DOI: 10.1016/j.colsurfb.2012.09.014] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2012] [Revised: 09/06/2012] [Accepted: 09/07/2012] [Indexed: 11/16/2022]
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Joo SW, Qian S. Electrophoretic motion of a nanorod along the axis of a nanopore under a salt gradient. J Colloid Interface Sci 2010; 356:331-40. [PMID: 21277582 DOI: 10.1016/j.jcis.2010.12.062] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2010] [Revised: 12/16/2010] [Accepted: 12/16/2010] [Indexed: 10/18/2022]
Abstract
The phoretic translation of a charged, elongated cylindrical nanoparticle, such as a DNA molecule and nanorod, along the axis of a nanopore driven by simultaneous axial electric field and salt concentration gradient, has been investigated using a continuum model, which consists of the Poisson-Nernst-Planck equations for the ionic concentrations and electric potential, and the Stokes equations for the hydrodynamic field. The induced particle motion includes both electrophoresis, driven by the imposed electric field, and diffusiophoresis, arising from the imposed salt concentration gradient. The particle's phoretic velocity along the axis of a nanopore is computed as functions of the imposed salt concentration gradient, the ratio of the its radius to the double-layer thickness, the nanorod's aspect ratio (length/radius), the ratio of the nanopore size to the particle size, the surface-charge density of the particle, and that of the nanopore in KCl solution. The diffusiophoresis in a nanopore mainly arises from the induced electrophoresis driven by the generated electric field, stemming from the double-layer polarization, and can be used to regulate electrophoretic translocation of a nanorod, such as a DNA molecule, through a nanopore. When both the nanorod and the nanopore wall are charged, the induced electroosmotic flow arising from the interaction of the overall electric field with the double layer adjacent to the nanopore wall has a significant effect on both electrophoresis driven by the imposed electric field and diffusiophoresis driven by the imposed salt gradient.
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Affiliation(s)
- Sang W Joo
- School of Mechanical Engineering, Yeungnam University, Gyongsan, South Korea
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Hsu JP, Liu KL, Hsu WL, Yeh LH, Tseng S. Diffusiophoresis of a soft sphere normal to two parallel disks. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2010; 26:16037-16047. [PMID: 20843051 DOI: 10.1021/la102631q] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
The diffusiophoresis of a soft spherical particle normal to two parallel disks subject to an applied ionic concentration gradient is modeled theoretically. The soft particle, which comprises a rigid core and a porous membrane layer, is capable of simulating a wide class of particles such as biocolloids and particles covered by an artificial membrane layer; a rigid particle can also be recovered as the limiting case where the membrane layer is infinitely thin. The problem considered simulates, for example, the chemotaxis of cells or microorganisms. We show that the presence of the membrane layer is capable of yielding complicated diffusiophoretic behavior when the sign of the charge carried by that layer is different from that on the surface of the rigid core of the particle. Both the sign and the magnitude of the diffusiophoretic velocity of a particle can be adjusted through varying the friction coefficient of its membrane layer. These results are of practical significance, for example, in the case where diffusiophoresis is adopted as a separation operation or as a tool to carry and/or control the rate of drug release.
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Affiliation(s)
- Jyh-Ping Hsu
- Department of Chemical Engineering, National Taiwan University, Taipei, Taiwan 10617.
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Joo SW, Lee SY, Liu J, Qian S. Diffusiophoresis of an Elongated Cylindrical Nanoparticle along the Axis of a Nanopore. Chemphyschem 2010; 11:3281-90. [DOI: 10.1002/cphc.201000433] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Yalcin SE, Lee SY, Joo SW, Baysal O, Qian S. Electrodiffusiophoretic motion of a charged spherical particle in a nanopore. J Phys Chem B 2010; 114:4082-93. [PMID: 20196581 DOI: 10.1021/jp100784p] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The electrodiffusiophoretic motion of a charged spherical nanoparticle in a nanopore subjected to an axial electric field and electrolyte concentration gradient has been investigated using a continuum model, composed of the Poisson-Nernst-Planck equations for the ionic mass transport and the Navier-Stokes equations for the flow field. The charged particle experiences electrophoresis in response to the imposed electric field and diffusiophoresis caused solely by the imposed concentration gradient. The diffusiophoretic motion is induced by two different mechanisms, an electrophoresis driven by the generated electric field arising from the difference of ionic diffusivities and the double layer polarization and a chemiphoresis due to the induced osmotic pressure gradient around the charged nanoparticle. The electrodiffusiophoretic motion along the axis of a nanopore is investigated as a function of the ratio of the particle size to the thickness of the electrical double layer, the imposed concentration gradient, the ratio of the surface charge density of the nanopore to that of the particle, and the type of electrolyte. Depending on the magnitude and direction of the imposed concentration gradient, one can accelerate, decelerate, and even reverse the particle's electrophoretic motion in a nanopore by the superimposed diffusiophoresis. The induced electroosmotic flow in the vicinity of the charged nanopore wall driven by both the imposed and the generated electric fields also significantly affects the electrodiffusiophoretic motion.
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Affiliation(s)
- Sinan E Yalcin
- Department of Aerospace Engineering, Old Dominion University, Norfolk, Virginia 23529, USA
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Hsu JP, Hsu WL, Liu KL. Diffusiophoresis of a charge-regulated sphere along the axis of an uncharged cylindrical pore. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2010; 26:8648-8658. [PMID: 20184368 DOI: 10.1021/la904726k] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
The diffusiophoresis of a charge-regulated spherical particle along the axis of a cylindrical pore is modeled. The problem considered allows us to examine simultaneously the effects of the presence of a boundary, the charge conditions on the particle surface, the thickness of the double layer, and the nature of a dispersion medium including its pH value and the diffusivities of the ionic species with respect to the diffusiophoretic behavior of a particle. We show that, in addition to the factors of double-layer polarization, electrophoresis, and the osmotic flow of solvent, the diffusiophoretic behavior of the particle can also be affected significantly by the electrical repulsive interaction between the particle and the co-ions immediately outside the double layer as they diffuse through the gap between the double layer and the pore. The last effect, which can influence the diffusiophoretic behavior of a particle both quantitatively and qualitatively, is absent in the diffusiophresis of a sphere in a spherical cavity. The competition of those effects yields many interesting results that are of practical significance in the design of a diffusiophoretic apparatus and/or the interpretation of experimental data.
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Affiliation(s)
- Jyh-Ping Hsu
- Department of Chemical Engineering, National Taiwan University, Taipei, Taiwan 10617.
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Lee SY, Yalcin SE, Joo SW, Baysal O, Qian S. Diffusiophoretic Motion of a Charged Spherical Particle in a Nanopore. J Phys Chem B 2010; 114:6437-46. [DOI: 10.1021/jp9114207] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Sang Yoon Lee
- School of Mechanical Engineering, Yeungnam University, Gyongsan 712-749, South Korea, and Department of Aerospace Engineering, Old Dominion University, Norfolk, Virginia 23529
| | - Sinan E. Yalcin
- School of Mechanical Engineering, Yeungnam University, Gyongsan 712-749, South Korea, and Department of Aerospace Engineering, Old Dominion University, Norfolk, Virginia 23529
| | - Sang W. Joo
- School of Mechanical Engineering, Yeungnam University, Gyongsan 712-749, South Korea, and Department of Aerospace Engineering, Old Dominion University, Norfolk, Virginia 23529
| | - Oktay Baysal
- School of Mechanical Engineering, Yeungnam University, Gyongsan 712-749, South Korea, and Department of Aerospace Engineering, Old Dominion University, Norfolk, Virginia 23529
| | - Shizhi Qian
- School of Mechanical Engineering, Yeungnam University, Gyongsan 712-749, South Korea, and Department of Aerospace Engineering, Old Dominion University, Norfolk, Virginia 23529
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Hsu JP, Liu KL, Hsu WL, Yeh LH, Tseng S. Diffusiophoresis of a Charge-Regulated Spherical Particle Normal to Two Parallel Disks. J Phys Chem B 2010; 114:2766-78. [DOI: 10.1021/jp907696t] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Jyh-Ping Hsu
- Department of Chemical Engineering, National Taiwan University, Taipei, Taiwan 10617
| | - Kuan-Liang Liu
- Department of Chemical Engineering, National Taiwan University, Taipei, Taiwan 10617
| | - Wei-Lun Hsu
- Department of Chemical Engineering, National Taiwan University, Taipei, Taiwan 10617
| | - Li-Hsien Yeh
- Department of Chemical Engineering, National Taiwan University, Taipei, Taiwan 10617
| | - Shiojenn Tseng
- Department of Mathematics, Tamkang University, Tamsui, Taipei, Taiwan 25137
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Hsu JP, Hsu WL, Ku MH, Chen ZS, Tseng S. Diffusiophoresis of a sphere along the axis of a cylindrical pore. J Colloid Interface Sci 2010; 342:598-606. [DOI: 10.1016/j.jcis.2009.10.043] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2009] [Revised: 10/19/2009] [Accepted: 10/20/2009] [Indexed: 11/26/2022]
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Zhang X, Hsu JP, Chen ZS, Yeh LH, Ku MH, Tseng S. Electrophoresis of a Charge-Regulated Soft Sphere in a Charged Cylindrical Pore. J Phys Chem B 2010; 114:1621-31. [DOI: 10.1021/jp9062093] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Xiaogang Zhang
- Department of Chemistry, Renmin University of China, Beijing, 100872, China
| | - Jyh-Ping Hsu
- Department of Chemical Engineering, National Taiwan University, Taipei, Taiwan 10617
| | - Zheng-Syun Chen
- Department of Chemical Engineering, National Taiwan University, Taipei, Taiwan 10617
| | - Li-Hsien Yeh
- Department of Chemical Engineering, National Taiwan University, Taipei, Taiwan 10617
| | - Ming-Hong Ku
- Department of Chemical Engineering, National Taiwan University, Taipei, Taiwan 10617
| | - Shiojenn Tseng
- Department of Mathematics, Tamkang University, Tamsui, Taipei, Taiwan 25137
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Lou J, Shih CY, Lee E. Diffusiophoresis of concentrated suspensions of spherical particles with charge-regulated surface: polarization effect with nonlinear poisson-Boltzmann equation. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2010; 26:47-55. [PMID: 19711921 DOI: 10.1021/la902113s] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Diffusiophoresis in concentrated suspensions of spherical colloids with charge-regulated surface is investigated theoretically. The charge-regulated surface considered here is the generalization of conventional constant surface potential and constant surface charge density situations. Kuwabara's unit cell model is adopted to describe the system and a pseudospectral method based on Chebyshev polynomial is employed to solve the governing general electrokinetic equations. Excellent agreements with experimental data available in literature were obtained for the limiting case of constant surface potential and very dilute suspension. It is found, among other things, that in general the larger the number of dissociated functional groups on particle surface is, the higher the particle surface potential, hence the larger the magnitude of the particle mobility. The electric potential on particle surface depends on both the concentration of dissociated hydrogen ions and the concentration of electrolyte in the solution. The electric potential on particle surface turns out to be the dominant factor in the determination of the eventual particle diffusiophoretic mobility. Local maximum of diffusiophoretic mobility as a function of double layer thickness is observed. Its reason and influence is discussed. Corresponding behavior for the constant potential situation, however, may yield a monotonously increasing profile.
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Affiliation(s)
- James Lou
- Department of Chemical Engineering, Institute of Polymer Science and Engineering, National Taiwan University, Taipei, Taiwan 10617
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Zhang X, Hsu WL, Hsu JP, Tseng S. Diffusiophoresis of a Soft Spherical Particle in a Spherical Cavity. J Phys Chem B 2009; 113:8646-56. [DOI: 10.1021/jp9014417] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Xiaogang Zhang
- Department of Chemistry, Renmin University of China, Beijing, 100872, China
| | - Wei-Lun Hsu
- Department of Chemical Engineering, National Taiwan University, Taipei, Taiwan 10617
| | - Jyh-Ping Hsu
- Department of Chemical Engineering, National Taiwan University, Taipei, Taiwan 10617
| | - Shiojenn Tseng
- Department of Mathematics, Tamkang University, Tamsui, Taipei, Taiwan 25137
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Hsu JP, Hsu WL, Chen ZS. Boundary effect on diffusiophoresis: spherical particle in a spherical cavity. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2009; 25:1772-1784. [PMID: 19123786 DOI: 10.1021/la803334a] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
The boundary effect on the diffusiophoretic behavior of a particle is analyzed theoretically by considering the diffusiophoresis of a charged sphere under arbitrary surface potential and double-layer thickness at an arbitrary position in an uncharged spherical cavity. We show that the phenomenon under consideration is governed by double-layer relaxation, chemiosmotic/diffusioosmotic flow, and two types of competing double-layer polarization. The presence of the cavity has a profound influence on the diffusiophoretic behavior of the particle, especially when the surface potential is high. For instance, the scaled diffusiophoretic velocity of the particle has a local maximum as the position of the particle varies; it may have a local maximum and local minimum as the thickness of the double-layer varies. The significance of the effect of double-layer relaxation depends upon the level of surface potential and magnitude of the electric Peclet number.
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Affiliation(s)
- Jyh-Ping Hsu
- Department of Chemical Engineering; National Taiwan University, Taipei, Taiwan 10617.
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