Synthesis and bioactive properties of macroporous nanoscale SiO₂-CaO-P₂O₅ bioactive glass

A macroporous nanoscale bulk bioactive glass (SiO₂-CaO-P₂O₅ system) was prepared by sol-gel co-template method. Porosimeter analysis showed that the as-synthesized bioactive glasses (BGs) had a porosity of 85% and exhibited a multimodal pore size distribution, nanopores (10-40 nm) and macropores (100 nm-10 μm). Morphological and structural characterizations showed the pores were interconnected with pore walls of about 250 nm in width and 1 μm in length. In vitro bioactivity test indicated that the as-synthesized bulk BGs exhibited faster apatite layer formation capability than the conventional sol-gel BGs. Additionally, the deposited layer was identified as hydroxycarbonate apatite, which is similar to the inorganic part of human bone.