Bioactive glasses (BGs) have been considered attractive materials for bone tissue engineering due to their reactivity with the surrounding biological environment. In addition, their osteoinductive and osteoconductive properties allow them to bond to hard tissue and stimulate bone formation [1]. In this process, the release of leaching products which occurs during the dissolution process of BGs, not only plays a therapeutic role in the osteogenic activation of cells but also influences properties such as antibacterial behavior and angiogenesis. Therefore, several BG compositions are developed containing metallic therapeutic ions, and interestingly less common ions like rare earth elements have been considered to enhance the intrinsic properties of glasses [2,3]. In this study, copper was incorporated in BG due to the reported stimulating effects of copper ions on angiogenesis, antibacterial properties and osteogenic differentiation of mesenchymal stem cells. Similarly, zinc ions have been shown to have anti-inflammatory effects and stimulation of bone formation [2]. This study aimed to evaluate the effect of incorporating different concentrations of copper and zinc ions into the composition of the melt-derived borosilicate 0106-B1 BG in terms of thermal properties, bioactive behaviour, ion release kinetics and antibacterial effect. In vitro bioactivity assessment was performed in simulated body fluid and characterized using SEM, FTIR and XRD. Additionally, antibacterial properties were evaluated against S. aureus and E. coli bacteria and the ion release kinetics was determined with ICP-OES. The results show the potential bioactive behavior of the Zn and Cu-doped bioactive glasses for application in bone tissue regeneration. Moreover, the incorporation of the studied ions led to glasses with concentration-dependent tunable dissolution and antibacterial effect.  
The authors acknowledge the funding of the German Research Foundation  (DFG).
 
1 Hench L.L., The story of Bioglass, J. Mater. Sci. Mater. Med. 2006, 17, 967–978
2 Hoppe A., et al., A review of the biological response to ionic dissolution products from bioactive glasses and glass-ceramics, Biomaterials 2011, 32(11) 2757-2774.
3 Pantulap, U., et al., Bioactive glasses incorporating less-common ions to improve biological and physical properties. Journal of Materials Science: Materials in Medicine 2022, 33(1), 1-41.