The coarsening of biomimetic condensates in an active fluid is non-self-similar

Nature Physics (2026)Cite this article Coarsening, the growth of larger structures at the expense of smaller ones, is a fundamental process in multiphase systems. The cell cytoplasm is an example of an out-of-equilibrium multiphase system in which molecular phase-separated condensates nucleate and grow within an active fluid composed of biopolymers and energy-consuming enzymes. Here we uncover the mechanisms that govern the growth of condensates in a self-stirring active fluid. We study the coarsening of synthetic DNA-based condensates embedded within a three-dimensional reconstituted cytoskeleton composed of microtubules and molecular motors. By combining experiments and modelling, we explain the absence of self-similarity in active coarsening and the origin of the continuously varying coarsening exponents for condensates within either active or passive fluids. The coarsening dynamics are set by the statistics of binary collisions among droplets, which depend on their size-dependent motility, irrespective of their active or passive origins. We find that the scaling exponent of the collision kernel is a unifying control parameter for the coarsening and the size distribution of motile condensates. Our results expand our understanding of phase separation in far-from-equilibrium systems, with potential implications in materials science and biology.This is a preview of subscription content, access via your institution Access Nature and 54 other Nature Portfolio journals Get Nature+, our best-value online-access subscription $32.99 / 30 days cancel any timeSubscribe to this journal Receive 12 print issues and online access $259.00 per yearonly $21.58 per issueBuy this articleUSD 39.95Prices may be subject to local taxes which are calculated during checkoutAll data generated or analysed during this study are included in the article and its Supplementary Information. Data are also available from the corresponding author on reasonable request. Source data are provided with this paper.The code used during this study is available via GitHub at http://github.com/Layne28/active-coarsening (ref. 45).Cugliandolo, L. F. Coarsening phenomena.

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GitHub https://github.com/Layne28/active-coarsening (2024).Download referencesThis work was supported primarily by the NSF CAREER award DMR-2047119 (J.L., A.T.C. and G.D.) and by the NSF-funded Brandeis Bioinspired MRSEC award DMR-2011846 (L.B.F., C.A. and A.B.). We thank S. Dalal, director of the Brandeis Biomaterial Facility, for help with protein purification. We also acknowledge the use of the optical, microfluidics and biomaterial facilities supported by the NSF MRSEC award DMR-2011846. W.B.R. acknowledges support from the Human Frontier Science Program (RGP0029).Department of Physics, Brandeis University, Waltham, MA, USAJeremy Laprade, Layne B. Frechette, Christopher Amey, Adrielle T. Cusi, Aparna Baskaran, W. Benjamin Rogers & Guillaume DuclosSearch author on:PubMed Google ScholarSearch author on:PubMed Google ScholarSearch author on:PubMed Google ScholarSearch author on:PubMed Google ScholarSearch author on:PubMed Google ScholarSearch author on:PubMed Google ScholarSearch author on:PubMed Google ScholarJ.L. performed the experiments and the simulations and analysed the data. L.B.F. and C.A. developed the computer codes for the simulations. A.T.C. performed the experiments for the coarsening in a passive fluid. A.B. and W.B.R. contributed materials and analysis tools. G.D. and W.B.R. performed experiments in the early stage of the project. G.D. supervised the project and wrote the paper. All co-authors provided feedback on the paper.Correspondence to Guillaume Duclos.The authors declare no competing interests.Nature Physics thanks Atul Parikh, David Zwicker and the other, anonymous, reviewer(s) for their contribution to the peer review of this work.Publisher’s note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.Discussion about the biological relevance and Supplementary Figs. 1–19.Coarsening of DNA droplets embedded in an active fluid.Tracking droplet trajectories advected by the active flows.Simulations of droplet coarsening in an active fluid.Simulations of coarsening for diffusive droplets with m = 1, 0 or −1.Tables with data points.Tables with data points.Tables with data points.Tables with data points.Tables with data points.Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.Reprints and permissionsLaprade, J., Frechette, L.B., Amey, C. et al. The coarsening of biomimetic condensates in an active fluid is non-self-similar. Nat. Phys. (2026). https://doi.org/10.1038/s41567-026-03191-wDownload citationReceived: 17 December 2024Accepted: 23 January 2026Published: 06 March 2026Version of record: 06 March 2026DOI: https://doi.org/10.1038/s41567-026-03191-wAnyone you share the following link with will be able to read this content:Sorry, a shareable link is not currently available for this article. Provided by the Springer Nature SharedIt content-sharing initiative