Synthesis of nanofibrous gelatin/silica bioglass composite microspheres using emulsion coupled with thermally induced phase separation

Abstract

This study proposes an innovative way of synthesizing porous gelatin/silica bioglass composite microspheres with a nanofibrous structure using emulsion coupled with thermally induced phase separation (TIPS). In particular, a mixture of the solvent (water) and non-solvent (ethanol) was used to induce a unique phase separation of gelatin/silica mixtures (ie. gelatin/silica hybrid-rich and liquid-rich phases) at -70 degrees C for the creation of a nanofibrous structure. All the composite microspheres synthesized with silica contents of 10 wt%, 15 wt%, and 20 wt% had well-defined spherical shapes between 124 and 136 pm in size. In addition, they were comprised of nanofibrous gelatin/silica composite walls (several tens of nanometers in thickness), where the sol-gel derived silica bioglass phase was uniformly distributed throughout the gelatin matrix. The in vitro apatite-forming ability and biocompatibility of the,nanofibrous gelatin/silica bioglass composite microspheres was significantly enhanced with an increase in silica content, demonstrating their great potential for the promotion of bone tissue regeneration. (C) 2016 Elsevier B.V. All rights reserved.