Direct Probing of the Phosphate-Ion Distribution in Bioactive Silicate Glasses by Solid-State NMR: Evidence for Transitions between Random/Clustered Scenarios
2013 (English)In: Chemistry of Materials, ISSN 0897-4756, E-ISSN 1520-5002, Vol. 25, no 9, 1877-1885 p.Article in journal (Refereed) Published
By employing P-31 multiple-quantum coherence-based solid-state nuclear magnetic resonance spectroscopy, we present the first comprehensive experimental assessment of the nature of the orthophosphate ion distributions in silicate based bioactive glasses (BGs). Results are provided both from melt prepared BG and evaporation-induced self-assembly-derived mesoporous bioactive glass (MEBG) structures of distinct compositions. The phosphate species are randomly dispersed in melt-derived BGs (comprising 44-55 mol % SiO2) of the Na2O-CaO-SiO2-P2O5 system, whereas a Si-rich (86 mol % SiO2) and Ca-poor ordered MBG structure exhibits nanometer-sized amorphous calcium phosphate clusters, conservatively estimated to comprise at least nine orthophosphate groups. A Ca-richer MBG (58 mol % SiO2) reveals a less pronounced phosphate clustering. We rationalize the variable structural role of P in these amorphous biomatetials.
Place, publisher, year, edition, pages
2013. Vol. 25, no 9, 1877-1885 p.
bioactive glasses, phosphate distribution, calcium phosphate clusters, multiple quantum coherence, 45S5 Bioglass
Materials Chemistry Physical Chemistry
Research subject Physical Chemistry
IdentifiersURN: urn:nbn:se:su:diva-92027DOI: 10.1021/cm400487aISI: 000319184600055OAI: oai:DiVA.org:su-92027DiVA: diva2:637309
FunderSwedish Research Council, 2009-7551, 2010-4943Knut and Alice Wallenberg Foundation