Fluidic\nMembrane-Bound Protocells Enabling Versatile\nAssembly of Functional Nanomaterials for Biomedical Applications

The\ndevelopment of membrane-bound protocells, which process cascade\nbiochemical reactions in distinct microcompartments, marks a significant\nadvancement in soft systems. However, many synthesized protocells\nwith cell membrane-like structures are prone to rupturing in biological\nenvironments and are challenging to functionalize, limiting their\nbiomedical applications. In this study, we explore the liquid–liquid\nphase separation of tannic acid (TA) and polyethylene glycol (PEG)\nto form coacervate droplets. Upon introducing polyvinylpyrrolidone\n(PVP) molecules, a dense hydrogen bonding network spontaneously forms\nat the surfaces of the coacervate droplets, resulting in robust fluidic\nmembrane-bound protocells (FMPs). These protocells can be flexibly\npostfunctionalized to incorporate functional nanomaterials via electrostatic\nattraction, enabling the design of cascade reactions for biomedical\napplications. To demonstrate this, nanozymes (Pt/CeO<sub>2</sub>)\nare assembled onto Fe<sup>3+</sup>/FMPs, resulting in functional FMPs\n(Pt/CeO<sub>2</sub>@Fe<sup>3+</sup>/FMPs) capable of catalyzing the\ndegradation of uric acid and its harmful byproduct, H<sub>2</sub>O<sub>2</sub>, offering potential treatments for gout.