Biological investigation of cobalt-containing and curcumin-loaded bioactive glass nanospheres for chronic wound healing applications.

Bioactive glasses have emerged as promising platforms for soft tissue regeneration. However, their effective application in wound healing requires the integration of multiple therapeutic functionalities. In this study, cobalt-doped and curcumin-loaded mesoporous bioactive glass nanospheres (MBGNs) were biologically evaluated as a delivery system designed to combine antimicrobial, antioxidant, anti-inflammatory, and vascularization-associated functionalities. The mesoporous structure allowed for the efficient incorporation of curcumin, with loading efficiencies reaching up to approximately 70%. The release profiles demonstrated sustained release of both cobalt and curcumin, providing a physicochemical basis for the biological responses observed in the present study. Total phenolic content (TPC) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) assays confirmed the presence of curcumin in the system, although the relatively low radical scavenging activity suggests a partial limitation in the accessibility of phenolic groups, possibly due to interactions with cobalt ions. Cytocompatibility assays using human fibroblasts (MRC-5 and NHDF) revealed high cell viability (over 93%) at concentrations ranging from 0.125 to 0.5 mg/mL. Antibacterial tests revealed sustained activity against Gram-positive (Staphylococcus aureus) and Gram-negative (Escherichia coli) strains. Furthermore, the biological performance was evaluated using in vitro wound closure and in ovo chorioallantoic membrane (CAM) assays. The results showed that the developed MBGNs were compatible with keratinocyte migration and that Co-containing formulations exhibited vascularization-related responses in the CAM model. Collectively, these findings suggest biological activities relevant to chronic wound management, including compatibility with cell migration and vascularization-associated responses. These observations support the potential use of cobalt-doped and curcumin-loaded MBGNs as bioactive carriers for chronic wound care applications, although further mechanistic and in vivo investigations are required to fully elucidate their therapeutic effects.