Core–shell alginate@silica microparticles encapsulating probiotics

Abstract

Lactobacillus rhamnosus GG (LGG) was encapsulated in core–shell alginate–silica microcapsules by coating the electrosprayed ionogel with a silica shell via hydrolysis/condensation of alkoxysilane precursors. The viability of encapsulated LGG highly depends on the mineralisation conditions (in aqueous or organic phases), identified as a critical step. More importantly, due to the unswelling of silica and to its mesoporosity that allows nutriment-metabolite diffusion, it was possible to avoid cell leakage and additionally insure bacterial growth inside the microcapsules. The results of this work gave a proof-of-concept for controlled bacterial proliferation in microcompartments, which have straightforward applications in oral delivery of probiotics.