Relationship between bioactivity and textural parameters in glasses

摘要

Four different glasses in the system SiO_2.p_2O_5.CaO.MgO with different silica and magnesium contents have been prepared by a sol-gel route. The glasses were calcined at 600deg C and characterised by chemical analysis, surface area (BET method), porosity and XPS. The in vitro bioactivity of the calcined samples was determined by immersion in a SBF solution. Surface area and porosity increases with the silica and magnesium content, while a strong inhibitory effect of magnesium on the hydroxyapatite (HA) growth rate is observed. XPS showed strong differences in the chemical composition of the bulk and surface of the glass. The relevance of this chemical heterogeneity and textural properties for the bioactivity behaviour of the glass is discussed.