Solvent-free strategy yields size and shape-uniform capsules

Abstract

Capsules with a liquefied core were fabricated via the assembly of polymeric droplets induced by superamphiphobic surfaces. These highly repellent substrates exhibit distinct features such as (i) an easy and precise control over the particle size and shape, (ii) a high encapsulation efficiency, (iii) mild processing conditions, and (iv) the possibility to include any object in either a water or oil-based liquid core, which are not found on the current available strategies. As proof of concept, a photo-cross-linkable derivative of chitosan was used to produce the polymeric shell while a wealth variety of template cores were tested using a reversible cross-linking mechanism, interfacial gelation process or ice. Owing to the widespread application of polymeric capsules, the developed strategy is poised to usher the development of the next generation of materials not only for biomedical purposes but also for cosmetics, agriculture and electronics.