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Field-Theoretic Simulation Method to Study the Liquid–Liquid Phase Separation of Polymers

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Phase-Separated Biomolecular Condensates

Part of the book series: Methods in Molecular Biology ((MIMB,volume 2563))

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Abstract

Liquid–liquid phase separation (LLPS) is a process that results in the formation of a polymer-rich liquid phase coexisting with a polymer-depleted liquid phase. LLPS plays a critical role in the cell through the formation of membrane-less organelles, but it also has a number of biotechnical and biomedical applications such as drug confinement and its targeted delivery. In this chapter, we present a computational efficient methodology that uses field-theoretic simulations (FTS) with complex Langevin (CL) sampling to characterize polymer phase behavior and delineate the LLPS phase boundaries. This approach is a powerful complement to analytical and explicit-particle simulations, and it can serve to inform experimental LLPS studies. The strength of the method lies in its ability to properly sample a large ensemble of polymers in a saturated solution while including the effect of composition fluctuations on LLPS. We describe the approaches that can be used to accurately construct phase diagrams of a variety of molecularly designed polymers and illustrate the method by generating an approximation-free phase diagram for a classical symmetric diblock polyampholyte.

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Acknowledgements

This research is supported by the National Institutes of Health (NIH) under Grant Number R01AG05605 and by the MRSEC Program of the National Science Foundation under Award No. DMR 1720256. The authors also acknowledge support from the National Science Foundation NSF under Award No. MCB-1716956. This research used resources of the Extreme Science and Engineering Discovery Environment (XSEDE, supported by the NSF Project TG-MCA05S027) and the Center for Scientific Computing from the California NanoSystems Institute UC Santa Barbara (CNSI) available through the Materials Research Laboratory (MRL): an NSF MRSEC (DMR-1720256) and NSF CNS-1725797.

Author information

Authors and Affiliations

  1. Department of Chemistry and Biochemistry, University of California, Santa Barbara, CA, USA

    Saeed Najafi

  2. Materials Research Laboratory, University of California, Santa Barbara, CA, USA

    Saeed Najafi

  3. Department of Chemistry, Western Washington University, Bellingham, WA, USA

    James McCarty

  4. Materials Research Laboratory, University of California, Santa Barbara, CA, USA

    Kris T. Delaney

  5. Materials Research Laboratory, University of California, Santa Barbara, CA, USA

    Glenn H. Fredrickson

  6. Department of Chemical Engineering, University of California, Santa Barbara, CA, USA

    Glenn H. Fredrickson

  7. Department of Chemistry and Biochemistry, University of California, Santa Barbara, CA, USA

    Joan-Emma Shea

  8. Department of Physics, University of California Santa Barbara, Santa Barbara, CA, USA

    Joan-Emma Shea

Authors
  1. Saeed Najafi
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  2. James McCarty
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  3. Kris T. Delaney
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  4. Glenn H. Fredrickson
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  5. Joan-Emma Shea
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Corresponding author

Correspondence to Joan-Emma Shea .

Editor information

Editors and Affiliations

  1. Department of Chemistry, University of Illinois at Chicago, Chicago, IL, USA

    Huan-Xiang Zhou

  2. Department of Physics, University of Illinois at Chicago, Chicago, IL, USA

    Jan-Hendrik Spille

  3. Department of Physics, University at Buffalo, State University, Buffalo, NY, USA

    Priya R. Banerjee

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© 2023 The Author(s), under exclusive license to Springer Science+Business Media, LLC, part of Springer Nature

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Najafi, S., McCarty, J., Delaney, K.T., Fredrickson, G.H., Shea, JE. (2023). Field-Theoretic Simulation Method to Study the Liquid–Liquid Phase Separation of Polymers. In: Zhou, HX., Spille, JH., Banerjee, P.R. (eds) Phase-Separated Biomolecular Condensates. Methods in Molecular Biology, vol 2563. Humana, New York, NY. https://doi.org/10.1007/978-1-0716-2663-4_2

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  • DOI: https://doi.org/10.1007/978-1-0716-2663-4_2

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  • Publisher Name: Humana, New York, NY

  • Print ISBN: 978-1-0716-2662-7

  • Online ISBN: 978-1-0716-2663-4

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