Commercial silicate-based bioglasses, including 45S5 glass have been subject of vast interest in the biomedical field for many years [1]. Several limitations of those commercial glasses, such as: limited degradability, low porosity and it generates an acidic medium that induce inflammatory response led to the development of silica-borate glass systems for biomedical applications [2-5]. Silica-borate systems can overcome some of the enumerated drawbacks, when used as part of composite systems. They can improve the strength of the composite through the reaction of the glass degradation products (e.g. cartions) with the polymeric matrices. Additionally, controlling the degradation it is possible to increase the porosity of composites.

The main objective of this work was to prepare silica-borate glass compositions by melt quenching. Glass compositions of general formula 0.20B₂O₃:0.40SiO₂:xMgO:yCaO: (0.35-x-y)SrO:0.05Na₂O (molar ratio, where x, y = 0.35 or 0.00, and x ≠ y) were synthesised, and composite fibres were prepared by wet spinning of a PLA solution containing a suspension of the glass particles. Fibre meshes of the processed fibres were prepared and their cytotoxicity was evaluated by direct contact with human osteosarcoma cell line Saos-2, throughout 7 days of incubation (37 ºC and 5 % CO₂ atmosphere). For day 1, 3 and 7, cell proliferation (DNA quantification method) and metabolic activity (MTS method) were monitored. Additionally, it was tested the water uptake and weight loss of the developed systems, as well as their capacity to form a calcium phosphate layer when immersed in simulated body fluid (SBF).

References:

1.         Hench, L., The story of Bioglass. Journal of Materials Science: Materials in Medicine, 2006. 17(11): p. 967-978.

2.         Juhasz, J. and S. Best, Bioactive ceramics: processing, structures and properties. Journal of Materials Science, 2012. 47(2): p. 610-624.

3.         Rahaman, M.N., W. Liang, and D.E. Day, Preparation and Bioactive Characteristics of Porous Borate Glass Substrates, in Advances in Bioceramics and Biocomposites: Ceramic Engineering and Science Proceedings. 2008, John Wiley & Sons, Inc. p. 1-10.

4.         Liang, W., et al., Bioactive borate glass scaffold for bone tissue engineering. Journal of Non-Crystalline Solids, 2008. 354(15-16): p. 1690-1696.

5.         Ning, J., et al., Synthesis and in vitro bioactivity of a borate-based bioglass. Materials Letters, 2007. 61(30): p. 5223-5226.