Microfluidic-Assisted Interfacial Polymerization for Continuous Fabrication of Biomimetic Microreactors

Inspired by the compartmentalized supramolecular structures in living cells for complex metabolic processes, many biomimetic compartmentalized structures including coacervates, emulsion microdroplets, liposomes, proteinosomes, and vesicles driven by non-covalent interactions have been created to serve as biomimetic microreactors. However, because of the intrinsic feature of non-covalent interactions, most of the biomimetic microreactors suffer from underwhelming stability. Here, we show continuous fabrication of robust biomimetic microreactors through microfluidic-assisted interfacial polymerization of polyamide acid (PAA). By distributing anhydride-based monomers and tris-hydrazide monomers in oil and water phases, respectively, PAA films are rapidly formed at the water–oil interface through the formation of amide bonds. By coupling the interfacial polymerization strategy with a microfluidic technique, together with a simple gelation of the encapsulated aqueous phase, robust microreactors protected by PAA films are continuously fabricated. The obtained microreactors show a uniform size of ∼185 μm and are found to be able to effectively load enzymes. As an application, an enzymatic self-assembly of supramolecular fibers in the microreactors that mimic the self-assembly of biological filaments inside living cells is demonstrated. This work may accelerate the scalable fabrication of stable biomimetic microreactors for conversion of chemicals.