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  • Open Access

Chemotaxis-Induced Phase Separation

Henrik Weyer1,*, David Muramatsu1,*, and Erwin Frey1,2,†

  • *These authors contributed equally to this work.
  • †Contact author: frey@lmu.de
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Phys. Rev. Lett. 135, 208402 – Published 10 November, 2025

DOI: https://doi.org/10.1103/2933-45qc

Abstract

Chemotaxis allows single cells to self-organize at the population level, as classically described by Keller-Segel models. We show that chemotactic aggregation can be understood using a generalized Maxwell construction based on the balance of density fluxes and reactive turnover. This formulation implies that aggregates generically undergo coarsening, which is interrupted and reversed by cell growth and death. Together, both stable and spatiotemporally dynamic aggregates emerge. Our theory mechanistically links chemotactic self-organization to phase separation and reaction-diffusion patterns.

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Coarsening dynamics of chemotactic aggregates

Henrik Weyer, David Muramatsu, and Erwin Frey
Phys. Rev. E 112, 054406 (2025)

Article Text

Supplemental Material

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Phys. Rev. Lett. 135, 208402– Published 10 November, 2025
  • Received 9 September 2024
  • Accepted 22 September 2025
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