Colloidosomes: "Smart" Materials for Biomedical Applications

Colloidosome-based microgels consist of an aqueous polymer gel core with a shell of colloidal particles adsorbed to the surface by electrostatic interactions. They have a wide range of possible applications including cell encapsulation, imaging and diagnostics, and drug delivery. The distribution and packing of the colloidal particles on the microgel determine the pore size, thereby enabling exact control of transport characteristics. In this study, we use sodium alginate as an aqueous gel scaffold, synthesized into microgels via microfluidics. Internal gelation of the alginate core is achieved by crosslinking with calcium ions while flowing in the microfluidic device. The shell consists of packed polystyrene nanoparticles which are functionalized to yield the appropriate charge.