Preparation and in vitro evaluation of ε-poly(L-lysine) immobilized poly(ε-caprolactone) nanofiber membrane by polydopamine-assisted decoration as a potential wound dressing material

Prevention of infection and elimination of excess reactive oxygen species are the key factors to achieve wound healing. In this study, we have developed a multifunctional poly(ε-caprolactone) nanofiber membrane modified by ε-poly ( L -lysine) (ε-PL) with the assistance of mussel-inspired polydopamine . The morphology of the nanofibrous membrane were observed by scanning electron microscopy and transmission electron microscopy . The chemical structure characterization by Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy demonstrated the successful modification of polydopamine and the immobilization of ε-PL. Photothermal effect assay proved that the temperature of the nanofiber membrane after near infrared photothermal treatment could reach the temperature required for antibacterial effect . The release of ε-PL exhibited an initial burst which was beneficial to achieve rapid bacteria inhibition. By combining ε-PL with near infrared photothermal therapy, a synergistic antibacterial effect was achieved against Escherichia coli and Staphylococcus aureus . The results of antioxidant activity assessment indicated that polydopamine on the nanofiber membranes served as an antioxidant agent to scavenge reactive oxygen species. Additionally, the nanofiber membranes showed good cytocompatibility and suitable mechanical properties close to the skin. In summary, the prepared membrane possessed intrinsically multifunctional properties showing great potential to be used as promising wound dressing materials.