Nanosized HCA-coated borate bioactive glass with improved wound healing effects on rodent model

Borate bioactive glass (BBG) stimulates angiogenesis and promotes cell growth. However, controlling the degradation rate of BBG and maintaining the critical concentration of bioactive ions suitable for cell promotion and differentiation remain great challenges in soft tissue repair. In this study, a novel approach was proposed to produce nanosized CO₃²⁻-containing hydroxyapatite (HCA)-coated BBG (nano-HCA@BG). Unlike the previously reported hard-to-degrade hydroxyapatite (HA) coating after static soaking treatment of BBG, the nano-HCA@BG, obtained by dynamically immersing the BBG powder in a flowing buffer, had a porous structure and was surface-coated with a layer of amorphous HCA, which improved the biocompatibility and retained the biodegradability of BBG. The effects of nano-HCA@BG were evaluated and compared with those of powdered BBG at the cellular and animal levels. The formation of the HCA-coated nanoporous architecture significantly improves biocompatibility, promotes cell growth and proliferation, and is beneficial for wound healing in rodent skin defects.