From nanoscale to microscale hierarchical multifunctional nano borate bioactive glass for efficient wound healing

The unique biodegradation and mineralization properties of nanosized CO32−- containing hydroxyapatite (HCA)-coated BBG (nano-HCA@BG) make it a promising material for soft tissue repair. However, its single-function solid powder form makes it difficult to control drug release rates, limiting its potential in vivo application. To address this challenge, we designed a hierarchical multifunctional composite by incorporating gelatin with nano-HCA@BG loaded with AgNPs. The hierarchical composite achieved a high degree of structural fit from nanometer to micrometer scale, as demonstrated by structural characterization results. The composite showed improved encapsulation of nanodrug and controlled degradation, as confirmed by degradation and antimicrobial property results. Wound healing experiments in vivo revealed efficient encapsulation of nano-HCA@BG through specific combination of gelatin and nano-HCA@BG, leading to improved controlled degradation and biological activity of the glass. The study also developed a dynamic flowing drug loading method that integrated material preparation and drug loading, thus improving the efficiency of drug loading of the nano-HCA@BG. Overall, our study demonstrates a new method for the preparation of hierarchical functional biomaterials of bioglass, laying the foundation for nano-HCA@BG to play an important role in tissue repair. Moreover, our findings suggest that better understanding of the structure and biological properties of nano-HCA@BG could expand its application in other biomedical fields such as drug delivery.