Preparation of composite membranes with high tensile strength and antibacterial properties based on Ag-nanoparticles deposition on bacterial cellulose/apocynum venetum

Bacterial cellulose (BC), a natural nanofiber synthesized by bacteria, possesses a distinctive three-dimensional structure. Moreover, it exhibits superior properties like high water-holding capacity, high biocompatibility, non-toxicity, and biodegradability, conferring it with tremendous application potential in wound healing. Nevertheless, the lack of antibacterial property of BC restricts the use of pure BC membrane in the biomedical field . In this study, using BC as the substrate, it was compounded with Apocynum venetum (Av) to fabricate Bacterial cellulose-Apocynum venetum membrane (BC-Av). Subsequently, a nanosilver solution was prepared by reducing the AgNO 3 solution with ethylene glycol, and Ag was uniformly deposited on the surface of the BC-Av membrane via supercritical carbon dioxide ( Sc -CO 2 ) fluid. The outcomes revealed that the Ag-loaded BC-Av membrane (BC-Av-Ag) exhibited excellent antibacterial efficacy against S. aureus and E. coli , reaching 99.8% and 99.5% respectively, along with superior mechanical properties such as higher tensile strength (1.65 ± 0.03 MPa), Young's modulus (6.5 ± 0.25 MPa), and fracture strain (32.5 ± 1.5%). Additionally, it was verified that this green composite material not only possesses high thermal stability but also enhances the hydrophilicity of BC. The combination of the biodegradability and biocompatibility of BC-Av and BC-Av-Ag membrane lays a foundation for their future application in medical protective materials.