Interfacial Microcompartmentalization by Kinetic Control of Selective Interfacial Accumulation

Reported here is a 2D, interfacial microcompartmentalization strategy governed by 3D phase separation. In aqueous polyethylene glycol (PEG) solutions doped with biotinylated polymers, the polymers spontaneously accumulate in the interfacial layer between the oil‐surfactant‐water interface and the adjacent polymer phase. In aqueous two‐phase systems, these polymers first accumulated in the interfacial layer separating two polymer solutions and then selectively migrated to the oil‐PEG interfacial layer. By using polymers with varying photopolymerizable groups and crosslinking rates, kinetic control and capture of spatial organisation in a variety of compartmentalized macroscopic structures, without the need of creating barrier layers, was achieved. This selective interfacial accumulation provides an extension of 3D phase separation towards synthetic compartmentalization, and is also relevant for understanding intracellular organisation. The phenomenon selective interfacial accumulation (SIA) is reported for an aqueous system. Based on interfacial migration, kinetic control and capture of the spatial organisation in a variety of compartmentalized macroscopic structures, without the need to create barrier layers between compartments, is possible. SIA opens an avenue for 3D phase separation approaches towards synthetic compartmentalized systems, and it is also relevant to understanding and mimicking intracellular organisation.