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Description
Bioactive glasses (BGs) are widely studied for bone regeneration primarily because of their ability to bond to living bone, which is attributed to the formation of a hydroxyapatite layer on the glass surface in contact with the body fluids. BGs can be used as carriers for inorganic therapeutic ions. One of them is cobalt which is able to target the cellular hypoxia inducible factor 1α (HIF-1α) pathway, resulting in the activation of a number of genes associated with angiogenesis and tissue regeneration.
Understanding the role of glass characteristics (chemical, structural and textural) is the key to control dissolution of therapeutic ions from their structure.
The Co-doped BGs from the basic SiO2–CaO–P2O5 system were produced using melt-quenching and sol-gel techniques. CoO was substituted for CaO in the amounts of 1-5 mol%. S2 and A2 groups of glasses, with the CaO/SiO2 molar ratio varied between 0.20 and 1.35 were obtained. Glasses were analyzed using 29Si and 31P MAS-NMR (magic angle spinning-nuclear magnetic resonance), XPS (X-ray photoelectron spectroscopy) and XANES (X-ray absorption near edge structure), and BET (Brunauer-Emmett-Teller nitrogen adsorption/desorption) methods. The materials were incubated in simulated body fluid (SBF) and deionized water (DW) for 14 days. ICP-OES (inductively coupled plasma optical emission spectrometry) technique was used to evaluate changes in the concentration of the ions in incubation media.
The results showed that CaO/SiO2 ratio, synthesis method, and the presence of Co ions strongly affected structure of glasses. XPS and XANES spectroscopies showed different oxygen coordination number of cobalt in prepared glasses. Significantly, both CaO/SiO2 ratio and synthesis method affected the solubility of ions (Si, Ca, P, Co) from the structure of glasses during incubation in media (SBF and DW).
This work was supported by the National Science Centre, Poland Grants nos. 2019/32/C/ST5/00386 (MD) and 2017/27/B/ST8/00195 (KCK).
| Speaker Country | Poland |
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