Mesoporous phosphate-based glasses prepared via sol-gel

In the present study, a mesoporous phosphate-based glass (MPG) in the P2O5-CaO-Na2O system was synthesised, for the first time, using a combination of sol-gel chemistry and supramolecular templating. A comparison between the structural properties, bioactivity and biocompatibility of the MPG with a non-porous phosphate-based glass (PG) of analogous composition prepared via the same sol-gel synthesis method, but in the absence of a templating surfactant is also presented. Results indicate that the MPG has enhanced bioactivity and biocompatibility compared to the PG, despite having similar local structure and dissolution properties. In contrast to the PG, the MPG shows formation of hydroxyl carbonate apatite (HCA) on its surface after 24 hours of immersion in simulated body fluid. Moreover, MPG shows enhanced viability of Saos-2 osteosarcoma cells after 7 days of culturing. This suggests that textural properties (porosity and surface area) play a crucial role in the kinetics of HCA formation and in interaction with cells. Increased efficiency of drug loading and release over non-porous PG systems was proved using the antimicrobial tetracycline hydrochloride as a drug model. This study represents a significant advance in the field of mesoporous materials for drug delivery and bone tissue regeneration as it reports, for the first time, the synthesis, structural characterisation and biocompatibility of mesoporous calcium phosphate glasses.In the present study, a mesoporous phosphate-based glass (MPG) in the P2O5-CaO-Na2O system was synthesised, for the first time, using a combination of sol-gel chemistry and supramolecular templating. A comparison between the structural properties, bioactivity and biocompatibility of the MPG with a non-porous phosphate-based glass (PG) of analogous composition prepared via the same sol-gel synthesis method, but in the absence of a templating surfactant is also presented. Results indicate that the MPG has enhanced bioactivity and biocompatibility compared to the PG, despite having similar local structure and dissolution properties. In contrast to the PG, the MPG shows formation of hydroxyl carbonate apatite (HCA) on its surface after 24 hours of immersion in simulated body fluid. Moreover, MPG shows enhanced viability of Saos-2 osteosarcoma cells after 7 days of culturing. This suggests that textural properties (porosity and surface area) play a crucial role in the kinetics of HCA formation and in interaction with cells. Increased efficiency of drug loading and release over non-porous PG systems was proved using the antimicrobial tetracycline hydrochloride as a drug model. This study represents a significant advance in the field of mesoporous materials for drug delivery and bone tissue regeneration as it reports, for the first time, the synthesis, structural characterisation and biocompatibility of mesoporous calcium phosphate glasses.