Brownian aggregation rate of colloid particles with several active sites
Abstract
We theoretically analyze the aggregation kinetics of colloid particles with several active sites. Such particles (socalled “patchy particles”) are well known as chemically anisotropic reactants, but the corresponding rate constant of their aggregation has not yet been established in a convenient analytical form. Using kinematic approximation for the diffusion problem, we derived an analytical formula for the diffusioncontrolled reaction rate constant between two colloid particles (or clusters) with several small active sites under the following assumptions: the relative translational motion is Brownian diffusion, and the isotropic stochastic reorientation of each particle is Markovian and arbitrarily correlated. This formula was shown to produce accurate results in comparison with more sophisticated approaches. Also, to account for the case of a low number of active sites per particle we used Monte Carlo stochastic algorithm based on Gillespie method. Simulations showed that such discrete model is required when this number is less than 10. Finally, we applied the developed approach to the simulation of immunoagglutination, assuming that the formed clusters have fractal structure.
 Authors:
 Institute of Chemical Kinetics and Combustion, Institutskaya 3, 630090 Novosibirsk (Russian Federation)
 (Russian Federation)
 JSC “VECTORBEST”, PO BOX 492, Novosibirsk 630117 (Russian Federation)
 Publication Date:
 OSTI Identifier:
 22420026
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Journal of Chemical Physics; Journal Volume: 141; Journal Issue: 6; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; ANISOTROPY; COLLOIDS; DIFFUSION; MONTE CARLO METHOD; PARTICLES; REACTION KINETICS; SIMULATION
Citation Formats
Nekrasov, Vyacheslav M., Yurkin, Maxim A., Chernyshev, Andrei V., Email: chern@ns.kinetics.nsc.ru, Physics Department, Novosibirsk State University, Pirogova 2, 630090 Novosibirsk, Polshchitsin, Alexey A., JSC “VECTORBEST”, PO BOX 492, Novosibirsk 630117, Yakovleva, Galina E., Maltsev, Valeri P., Physics Department, Novosibirsk State University, Pirogova 2, 630090 Novosibirsk, and Department of Preventive Medicine, Novosibirsk State Medical University, Krasny Prospect 52, 630091 Novosibirsk. Brownian aggregation rate of colloid particles with several active sites. United States: N. p., 2014.
Web. doi:10.1063/1.4892163.
Nekrasov, Vyacheslav M., Yurkin, Maxim A., Chernyshev, Andrei V., Email: chern@ns.kinetics.nsc.ru, Physics Department, Novosibirsk State University, Pirogova 2, 630090 Novosibirsk, Polshchitsin, Alexey A., JSC “VECTORBEST”, PO BOX 492, Novosibirsk 630117, Yakovleva, Galina E., Maltsev, Valeri P., Physics Department, Novosibirsk State University, Pirogova 2, 630090 Novosibirsk, & Department of Preventive Medicine, Novosibirsk State Medical University, Krasny Prospect 52, 630091 Novosibirsk. Brownian aggregation rate of colloid particles with several active sites. United States. doi:10.1063/1.4892163.
Nekrasov, Vyacheslav M., Yurkin, Maxim A., Chernyshev, Andrei V., Email: chern@ns.kinetics.nsc.ru, Physics Department, Novosibirsk State University, Pirogova 2, 630090 Novosibirsk, Polshchitsin, Alexey A., JSC “VECTORBEST”, PO BOX 492, Novosibirsk 630117, Yakovleva, Galina E., Maltsev, Valeri P., Physics Department, Novosibirsk State University, Pirogova 2, 630090 Novosibirsk, and Department of Preventive Medicine, Novosibirsk State Medical University, Krasny Prospect 52, 630091 Novosibirsk. 2014.
"Brownian aggregation rate of colloid particles with several active sites". United States.
doi:10.1063/1.4892163.
@article{osti_22420026,
title = {Brownian aggregation rate of colloid particles with several active sites},
author = {Nekrasov, Vyacheslav M. and Yurkin, Maxim A. and Chernyshev, Andrei V., Email: chern@ns.kinetics.nsc.ru and Physics Department, Novosibirsk State University, Pirogova 2, 630090 Novosibirsk and Polshchitsin, Alexey A. and JSC “VECTORBEST”, PO BOX 492, Novosibirsk 630117 and Yakovleva, Galina E. and Maltsev, Valeri P. and Physics Department, Novosibirsk State University, Pirogova 2, 630090 Novosibirsk and Department of Preventive Medicine, Novosibirsk State Medical University, Krasny Prospect 52, 630091 Novosibirsk},
abstractNote = {We theoretically analyze the aggregation kinetics of colloid particles with several active sites. Such particles (socalled “patchy particles”) are well known as chemically anisotropic reactants, but the corresponding rate constant of their aggregation has not yet been established in a convenient analytical form. Using kinematic approximation for the diffusion problem, we derived an analytical formula for the diffusioncontrolled reaction rate constant between two colloid particles (or clusters) with several small active sites under the following assumptions: the relative translational motion is Brownian diffusion, and the isotropic stochastic reorientation of each particle is Markovian and arbitrarily correlated. This formula was shown to produce accurate results in comparison with more sophisticated approaches. Also, to account for the case of a low number of active sites per particle we used Monte Carlo stochastic algorithm based on Gillespie method. Simulations showed that such discrete model is required when this number is less than 10. Finally, we applied the developed approach to the simulation of immunoagglutination, assuming that the formed clusters have fractal structure.},
doi = {10.1063/1.4892163},
journal = {Journal of Chemical Physics},
number = 6,
volume = 141,
place = {United States},
year = 2014,
month = 8
}

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