Synthesis and bioactivity of sol-gel derived porous, bioactive glass microspheres using chitosan as novel biomolecular template

This article reports a novel, simple route for synthesis of sol-gel derived porous, bioactive glass (BG) microspheres using chitosan (CTS) as a biomolecular template in the acid-catalyzed sol-gel process. The use of CTS, which is a natural biocompatible polymer with a unique molecular structure, allowed the synthesis of BG microparticles with a spherical shape, 5-10 μm in size. Furthermore, pores with a size of 5-40 nm were created entirely throughout BG microspheres, which were formed by removing the network of CTS present initially in the CTS-BG composite microparticles via heat-treatment at 600°C for 2 h. These porous BG microspheres induced the vigorous precipitation of apatite crystals on their surface when immersed in simulated body fluid for 24 h, thus suggesting their excellent bioactivity.