Tailoring the biological response of mesoporous bioactive materials

Mesoporous bioactive glasses (MBGs) in the SiO₂-CaO-P₂O₅ system have been prepared using different non-ionic structure directing agents (SDA): Brij58, F68, P123 and F127. For the first time, the bioactive response of MBGs can be tailored with the kind of SDA incorporated. This is because, in addition to the textural properties, we can use the SDA to tailor the local atomic environment within the MBG struts. These features lead to differences in the in vitro bioactive behaviour of MBGs. Among the different SDAs used in this work, the triblock copolymer F68 leads to MBGs that exhibit the fastest bioactivity and the fastest differentiation induction from a pre-osteoblast to an osteoblast phenotype. These results are explained in terms of a highly ordered mesoporous structure, more free calcium cations acting as silica network modifiers and small mesopores that avoid the formation of CaP nuclei within pores, which could obstruct the ionic exchange with the surrounding fluids.