Hafnium/copper co-modified bioactive glass-ceramics: Physicochemical characteristics, in vitro bioactivity, antibacterial activity, and cytocompatibility

Bioactive glasses' innate capacity to form a link with bone and promote regeneration has drawn interest in bone tissue engineering. Hafnium, a minimally explored dopant and copper, an effective antimicrobial agent, were added to a silicate-based bioactive glass matrix. We have explored the physicochemical characteristics, biological performance and antibacterial properties of hafnium- and copper co-doped bioglass. The surface morphology and structural features of the prepared samples were investigated using scanning electron microscopy (SEM) and transmission electron microscopy (TEM), confirming the coexistence of micro- and nanoscale structural features. The improved apatite layer development in hafnium- and copper-doped bioglass [HC/BG-5 (hafnium 0.5 mol% and copper 1 mol% co-doped bioglass) sample was confirmed by in vitro bioactivity evaluation. Due to the interference of hafnium and copper with bacterial metabolism, the doped materials demonstrated significant antibacterial activity. Using MC3T3-E1 pre-osteoblast cells, research on cell survival and proliferation (CCK-8 and flow cytometry) showed that hafnium incorporation triggered the cellular response. Wound healing assays using MC3T3 pre-osteoblast and 3T3 fibroblast cells demonstrated that HC/BG-5 exhibited promising in-vitro wound-healing potential. These results emphasise the potential for advanced orthopaedic applications by showing that hafnium and copper doping improved the bioactivity and antibacterial efficacy of bioglass.