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Chemotactic particles as strong electrolytes: Debye-Hückel approximation and effective mobility law
Pierre Illien1, Ramin Golestanian2,3
1Laboratoire PHENIX (Physico-Chimie des Électrolytes et Nanosystèmes Interfaciaux), CNRS, Sorbonne Université, 4 Place Jussieu, 75005 Paris, France.
The Journal of Chemical Physics
|April 16, 2024
Summary
Chemically active particles in a binary mixture exhibit effective phoretic mobility that decays with concentration. This finding extends electrolyte conductivity laws to systems with long-range nonreciprocal interactions.
Area of Science:
- Physical Chemistry
- Chemical Physics
- Soft Matter Physics
Background:
- Chemically active particles generate concentration fields, leading to inter-particle interactions.
- Understanding particle transport in complex mixtures is crucial for nanoscale phenomena.
Purpose of the Study:
- To analytically calculate the effective phoretic mobility of a binary mixture of active particles.
- To investigate the concentration dependence of particle mobility under external gradients.
Main Methods:
- Analytical calculation of effective phoretic mobility.
- Leading-order approximation in overall concentration.
- Analogy with strong electrolyte modeling.
Main Results:
- Effective phoretic mobility decays with the square root of concentration.
- Derived a nonequilibrium counterpart to Kohlrausch and Debye-Hückel-Onsager laws.
- Identified a regime of maximal mobility.
Conclusions:
- The study extends electrolyte conductivity laws to active particles with nonreciprocal interactions.
- The derived mobility law offers insights into nanoscale transport.
- Potential applications in biological systems like living cells.
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