Preparation of cellulose acetate/polycaprolactone double-layer electrospinning film loaded with AgNPs@CuO particles and its antibacterial application

Cellulose acetate (CA), an essential biocompatible polymer for medical dressings, requires integration with antimicrobial agents (e.g., antibiotics, silver nanoparticles) due to its inherent non-antimicrobial nature. While silver nanoparticles (AgNPs) offer broad-spectrum activity, their cytotoxicity caused by uncontrolled ion release remains a critical challenge. Herein, we report a green synthesis strategy using dopamine hydrochloride as both a reducing agent and interfacial modifier to in situ synthesize AgNPs on copper oxide (CuO) surfaces, achieving precise silver ion regulation through CuO-dopamine coordination. The optimized AgNPs@CuO composites were embedded into CA nanofibers via electrospinning, followed by the construction of a polycaprolactone (PCL) supporting layer to form a bilayer membrane. Remarkably, the PCL/CA/AgNPs@CuO membrane exhibited a significant increase in tensile strength compared to monolayer CA, while maintaining adequate porosity for optimal breathability. The CA/AgNPs@CuO nanofiber membrane achieved inhibition zone diameters of 3.9 mm and 4.7 mm against E. coli and S. aureus , respectively, and demonstrated continuous antimicrobial release over 36 h, ensuring long-term antibacterial efficacy. This hierarchically designed system provides a paradigm for developing robust antimicrobial dressings with balanced biocompatibility and durability.