Synthesis and cytocompatibility of porous chitosan–silicate hybrids for tissue engineering scaffold application

Chitosan–silicate hybrids with 3D porous structures were prepared with freeze-drying precursor solutions derived from chitosan and γ-glycidoxypropyltrimethoxysilane (GPTMS). They were formed easily in any shape, such as sheets, pellets, disks, granules, and even roll-cakes. The pore size was strongly dependent on the freezing temperature: lower freezing temperature resulted smaller pores, about 110 μm for the hybrids frozen at −20 °C, and about 50 μm for those at −85 °C. The pore size was little dependent on the GPTMS content. In contrast, the GPTMS content affected porosity a littlie: ∼80% for chitosan, and ∼90% for the GPTMS-containing hybrids. Thus, their porous microstructure was controllable due to the freezing temperature and composition. MG63 osteoblastic cells were cultured up to 7 days on the porous hybrids. The cells adhered on the pore walls, proliferated, and migrated deep into the pore structure. It was thus concluded that the present chitosan–silicate hybrids were promising for tissue engineering scaffold applications.