Structural characterization of bioactive glasses by solid state NMR

Effect of boron incorporation on the bioactivity, structure, and mechanical properties of ordered mesoporous bioactive glasses

“…Moreover, we performed in vitro bioactivity tests and nanoindentation studies and correlated the changes in bioactivity and mechanical properties with the changes in glass structure revealed by in-depth solid-state nuclear magnetic resonance (NMR) spectroscopic studies. While solid state NMR has been widely used for the structural characterization of bioglasses, 20 to date the literature on boron-containing systems is rather limited. Work by the Eden group stands out, in particular reporting detailed compositional dependences and advanced connectivity information on the basis of twodimensional dipolar NMR spectroscopy in traditional meltquenched bioglasses.…”

Structural and thermal behavior of 45S5 Bioglass®‐based compositions containing alumina and strontium

“…In respect of glass network arrangement, both P 5+ and Si 4+ tend to occur in tetrahedral coordination in oxide glasses. However, when the two elements are present in suchlike 45S5 compositions and for bioactive purposes, silicon will always act as network‐former dictating the network‐polymerization and phosphorous predominantly as orthophosphate ions cooperating to ensure the ionic mobility in aqueous medium by an accessible structure . Figure shows 29 Si MAS‐NMR spectra and Table specifies the deconvolution components and their percentages calculated from fractional areas.…”

“…Furthermore, comparing the samples with BioH, it can be noticed that their center presented a slight displacement toward higher ppm values, that is, sodium orthophosphate environment. That throw could suggest a greater contribution of Q Si 2 structure . The 29 Si MAS‐NMR chemical shift previously discussed evidence of this suggestion.…”

“…That throw could suggest a greater contribution of Q Si 2 structure. 38,42 The 29 Si MAS-NMR chemical shift previously discussed evidence of this suggestion. Figure 5B shows 23 Na MAS-NMR spectra of the glasses.…”

“…However, when the two elements are present in suchlike 45S5 compositions and for bioactive purposes, silicon will always act as network-former dictating the network-polymerization and phosphorous predominantly as orthophosphate ions cooperating to ensure the ionic mobility in aqueous medium by an accessible structure. [38][39][40][41] Figure 4 shows 29 Si MAS-NMR spectra and Table 3 . For instance, the fractional area of Q Si 3 changed from 56 for BioH to 77% for BioAlSr.…”