Improved Mechanical Stability and Regulated Gentamicin-Release of Polyvinyl Alcohol/Chitosan Nanofiber Membranes via Heat Treatment

For wound dressing applications, nanofiber membranes must have adequate mechanical strength when cultured in vitro for cell ingrowth and matrix production, and the ability to withstand stresses in vivo. Moreover, effective polymeric drug carriers must also regulate and prolong drug release while preserving drug stability. This study addresses these requirements by utilizing heat treatment (100°C for 2 h) to improve the mechanical stability and regulated drug-release characteristics of electrospun gentamicin-loaded polyvinyl alcohol/chitosan (PVA/CS) nanofiber membranes. Electrospinning solutions with varying gentamicin concentrations produced defect-free and uniform nanofibers. The nanofiber membranes were characterized using scanning electron microscopy, Fourier transform infrared spectroscopy, and tensile testing, and their in vitro biodegradation and drug-release behavior were investigated. Tensile results revealed that heat treatment improved the mechanical strength of PVA and PVA/CS nanofibers, with gentamicin-loaded samples maintaining stability post-treatment. Gentamicin in the heat-treated nanofiber membranes exhibited controlled drug-release profiles, with reduced initial burst release and sustained release for 25 h. Furthermore, drug release was found to occur through the Fickian diffusion mechanism based on the Korsmeyer–Peppas model. These findings demonstrate that heat treatment is effective for achieving mechanical stability and regulated drug release, making it a safe alternative to chemical cross-linking for the biomedical applications of drug-loaded PVA/CS nanofiber membranes.