Novel ion-doped mesoporous glasses for bone tissue engineering: Study of their strctural characteristics influenced by the presence of phosphorous oxide

TL;DR

This study investigates how phosphorous oxide affects the structure of ion-doped mesoporous bioactive glasses, revealing increased mesoporosity order and ion entrapment, which could enhance their suitability for bone tissue engineering.

Contribution

It demonstrates that P2O5 incorporation increases network connectivity and captures metallic ions, improving mesoporous structure and potential bioactivity of the glasses.

Findings

P2O5 increases mesoporosity order.

P2O5 captures dopant ions, preventing network modification.

Glass structure influenced by cation type in phosphate clusters.

Abstract

Ion-doped binary SiO2-CaO and ternary SiO2-CaO-P2O5 mesoporous bioactive glasses were synthesised and characterised to evaluate the influence of P2O5 in the glass network structure. Strontium, copper and cobalt oxides in a proportion of 0.8 mol% were selected as dopants because the osteogenic and angiogenic properties reported for these elements. Although the four glass compositions investigated presented analogous textural properties, TEM analysis revealed that the structure of those containing P2O5 exhibited an increased ordered mesoporosity. Furthermore, 29Si NMR revealed that the incorporation of P2O5 increased the network connectivity and that this compound captured the Sr2+, Cu2+ and Co2+ ions preventing them to behave as modifiers of the silica network. In addition, 31P NMR results revealed that the nature of the cation directly influences the characteristics of the phosphate clusters. In this study, we have proven that phosphorous oxide entraps doping-metallic ions, granting these glasses with a greater mesopores order.