Elucidating the effect of CaF 2 on structure, biocompatibility and antibacterial properties of S53P4 glass

TitleElucidating the effect of CaF 2 on structure, biocompatibility and antibacterial properties of S53P4 glass
Publication TypeJournal Article
Year of Publication2020
AuthorsPrasad, S, Ganisetti, S, Jana, A, Kant, S, Sinha, PK, Tripathy, S, Illath, K, Ajithkumar, TG, Annapurna, K, Allu, AR, Biswas, K
JournalJournal of Alloys and Compounds
Volume831
Pagination154704
Date PublishedAUG
Type of ArticleArticle
ISSN0925-8388
KeywordsFluoride bioactive glasses, In vitro apatite formation and bactericidal action, MAS-NMR spectroscopy, MD simulations
Abstract

The present work focuses on the synthesis and structural elucidation of fluoride containing bioactive glasses in the system (in mol%) given by (53.86) SiO2 – (22.65) Na2O – (21.77-x) CaO – (1.72) P2O5 – x CaF2, where, x = 0, 5.44, 10.885 and 16.33. The role of the incorporated fluoride and its distribution within the glass were interpreted and analyzed using Molecular dynamics (MD) simulations and the results were compared with the modified random network (MRN) model. The interpretations from the model have been verified using the MAS-NMR spectroscopy technique. According to this model, fluoride containing bioactive glasses have been proposed to consist of silicate rich network regions and modifier cation – fluoride rich inter-network regions. The interface region was found to consist of non-bridging oxygen species (NBO) and phosphate cations which are either isolated orthophosphates (Q0P) or bridged with silicates in the form of pyrophosphate (Q1P) units forming Si–O–P bonds. The gradual substitution of CaF2 for CaO in the base glass resulted in an increase in the silicate network connectivity with a reduction in the NBOs and lead to an increase in the association of modifier cations with fluoride ions. However, fluoride ions were found to show a marginal preference to associate with Na+ cations leading to a decrease in the association of Na+ ions with orthophosphate and silicate units. These overall structural findings were correlated with the in vitro ion dissolution behaviour of the bioactive glasses as well as with the thermal properties. The glasses were tested for their in vitro cell viability towards mouse osteoblast type (MC3T3) cells in which fluoride containing bioactive glasses did not show any toxicity and exhibited better cell proliferation. The antibacterial efficacy of the fluoride containing glasses was tested at various concentrations (5, 10 and 20 mg/ml) in E.coli bacterial inoculum in which bactericidal action was evidenced.

DOI10.1016/j.jallcom.2020.154704
Type of Journal (Indian or Foreign)

Foreign

Impact Factor (IF)

5.316

Divison category: 
Central NMR Facility
Physical and Materials Chemistry

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