Print Email Facebook Twitter pH-Controlled Coacervate-Membrane Interactions within Liposomes Title pH-Controlled Coacervate-Membrane Interactions within Liposomes Author Last, M.G.F. (TU Delft ImPhys/Microscopy Instrumentation & Techniques; Kavli institute of nanoscience Delft) Deshpande, S.R. (TU Delft BN/Cees Dekker Lab; Kavli institute of nanoscience Delft; Wageningen University & Research) Dekker, C. (TU Delft BN/Cees Dekker Lab; Kavli institute of nanoscience Delft) Date 2020 Abstract Membraneless organelles formed by liquid-liquid phase separation are dynamic structures that are employed by cells to spatiotemporally regulate their interior. Indeed, complex coacervation-based phase separation is involved in a multitude of biological tasks ranging from photosynthesis to cell division to chromatin organization, and more. Here, we use an on-chip microfluidic method to control and study the formation of membraneless organelles within liposomes, using pH as the main control parameter. We show that a transmembrane proton flux that is created by a stepwise change in the external pH can readily bring about the coacervation of encapsulated components in a controlled manner. We employ this strategy to induce and study electrostatic as well as hydrophobic interactions between the coacervate and the lipid membrane. Electrostatic interactions using charged lipids efficiently recruit coacervates to the membrane and restrict their movement along the inner leaflet. Hydrophobic interactions via cholesterol-tagged RNA molecules provide even stronger interactions, causing coacervates to wet the membrane and affect the local lipid-membrane structure, reminiscent of coacervate-membrane interactions in cells. The presented technique of pH-triggered coacervation within cell-sized liposomes may find applications in synthetic cells and in studying biologically relevant phase separation reactions in a bottom-up manner. Subject coacervatesliposomesliquid−liquid phase separationmembranesmicrofluidics To reference this document use: http://resolver.tudelft.nl/uuid:056d1c01-c0b3-4a3f-96fa-3e62634d6f69 DOI https://doi.org/10.1021/acsnano.9b10167 ISSN 1936-086X Source ACS Nano (online), 14 (4), 4487-4498 Part of collection Institutional Repository Document type journal article Rights © 2020 M.G.F. Last, S.R. Deshpande, C. Dekker Files PDF acsnano.9b10167.pdf 7.43 MB Close viewer /islandora/object/uuid:056d1c01-c0b3-4a3f-96fa-3e62634d6f69/datastream/OBJ/view