"Bioactive glasses (BGs) are being increasingly investigated as antibacterial materials for developing scaffolds for bone tissue engineering (TE). Such applications are based on the biochemical reactions occurring on the BG surface in contact with the biological environment, which involve the (controlled) release of biologically active ions during BG scaffold degradation. Such ions are capable of stimulating specific cellular responses involved in bone tissue growth . In addition, BGs can induce immunomodulatory effects to trigger bone regeneration and wound healing . Expressing a further functionality of BGs, specific compositions are designed to release ions with antibacterial effect (Ag, Cu, Zn, Ga among other).
In this presentation, ion doped BGs will be discussed in the broad context of their use in bone tissue engineering. In particular, results will be presented to illustrate the osteogenic, angiogenic and antibacterial effect of a series of silicate and borate BGs. Specific concentrations of such ions enhance the secretion of vascular endothelial growth factor and the different mechanisms by which different ions induce angiogenesis will be discussed. The results of vitro studies will be presented that show the effect of ion concentration (following BG dissolution) on stem cell behavior. In an attempt to enhance the mechanical and biological performance of BG scaffolds, the polymer coating approach will be discussed. Such coatings (using synthetic or natural polymers) provide additional functionalities , for example, incorporating mesoporous BG nanoparticles as therapeutic drug carriers. Thus, the dual, simultaneous and tuned release of biologically active ions and therapeutic drugs (both antibiotics and growth factors) from BG scaffolds can be exploited to induce synergistic antibacterial, osteogenic and angiogenic effects.
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 T. Reiter; et al. Bioactive glass based scaffolds coated with gelatin for the sustained release of icariin. Bioactive Mater. 4 (2019) 1-7. "