ION RELEASE BEHAVIOR OF SILICOPHOSPHATE GLASSES CONTAINING SIX-FOLD COORDINATED SILICON STRUCTURE

: To facilitate the efficient use of phosphate-based glasses in various biomedical applications, it is essential to understand the effects of ion-releasing in the living body. In this work, the ion-releasing behavior of silicophosphate glass, designed as a supply source of silicate and phosphate ions that are effective for bone formation, was investigated. Two types of P 2 O 5 -SiO 2 -CaO-Na 2 O glasses containing 45–50 mol% of P 2 O 5 with both four- and six-fold coordinated silicon structures were prepared. The glass with ~50 mol% of P 2 O 5 content had a higher proportion of six-fold coordinated silicon structure, and it showed a lower ionic release to a simulated body fluid than that with ~45 mol% P 2 O 5 content. The release of the therapeutic ions from the silicophosphate glass can be effectively controlled by choosing their composition.