interfacial cross-linking is derived from interfacial polycondensation, and was developed to avoid the use of toxic diamines, for pharmaceutical or cosmetic applications. in this method, the small bifunctional monomer containing active hydrogen atoms is replaced by a biosourced polymer, like a protein. when the reaction is performed at the interface of an emulsion, the acid chloride reacts with the various functional groups of the protein, leading to the formation of a membrane. the method is very versatile, and the properties of the microcapsules (size, porosity, degradability, mechanical resistance) can be customized. flow of artificial microcapsules in microfluidic channels: