Characterization of aqueous interactions of copper-doped phosphate-based glasses by vapour sorption

45S5 bioactive glass reactivity by dynamic vapour sorption

“…However, recent work has demonstrated a dramatic increase in mass change in vapour sorption isotherm with phosphate based glasses. It was proposed that this was due to deliquescence and the formation of a saturated layer at the surface of dissolution products of glasses [22]. In this study, a similar trend was observed with the BG samples and thus the inflection point can be attributed to the deliquescence RH of BG of distinct surface areas.…”

“…The ion release rates were increased with a decrease in particle size, except for phosphorous, which decreased and may be attributed to the formation of calciumphosphate precipitate [7]. The linear relationship between ion release rates and sorption rates showed the ability of DVS in predicting the reactivity of BG particles, as has been previously described for phosphatebased glasses [22].…”

“…Dynamic vapour sorption (DVS) is a gravimetric technique that measures vapour sorption (i.e., change in mass) by a material under controlled variable relative humidity values. DVS, which has mainly been used in the pharmaceutical [20] and food science [21] fields, has recently been used to analyse the reactivity and aqueous interactions of soluble phosphate based glasses [22]. In addition to more accurately measuring mass changes in real-time, DVS is also more rapid than traditional submersion methods [22].…”

“…DVS, which has mainly been used in the pharmaceutical [20] and food science [21] fields, has recently been used to analyse the reactivity and aqueous interactions of soluble phosphate based glasses [22]. In addition to more accurately measuring mass changes in real-time, DVS is also more rapid than traditional submersion methods [22]. Furthermore, this technique potentially allows for BG-aqueous reactions without the loss of hydrated material that occurs during common reactivity tests, thus enabling the analysis of structural changes occurring at the surface of the glasses.…”

Effect of sodium on bioactive sol-gel-derived borate glasses

“…In terms of textural properties, the observed increase in surface area can be attributed to glasses with higher network connectivity (i.e., less network modifiers such as sodium), as previously observed with SGBGs [40] and other sol-gel systems [16]. DVS has previously been used to examine the reactivity of other bioactive glass systems based on silicate [60] and phosphate [61]. After 6 h, the ~12% mass change in Na0 particles (SSA = 168 ± 8 m 2 /g) was less than the ~48% of the Na24 particles (SSA = 91 ± 4 m 2 /g), which demonstrated that the atomic and molecular structures, not specific surface area, have dominant roles on the chemical durability of multicomponent glasses [19,62].…”