Dual controlled release nanomicelle-in-nanofiber system for long-term antibacterial medical dressings

Long-term antibacterial medical dressings can prevent infection as skin wounds heal. In this study, we used the hydrophobic antibacterial drug amoxicillin as a model to prepare drug-loaded nanomicelles using a film dispersion-hydration method, and drug-loaded nanomicelles were coaxially electrospun into nanofiber to create a novel nanomicelle-in-nanofiber (NM-in-NF) drug delivery system. Scanning electron microscopy and transmission electron microscopy were used to characterize the morphology of nanomicelles and nanofibers. Thermal property of as-prepared samples was tested using differential scanning calorimetry. The drug release behavior, cytotoxicity, and antibacterial properties of NM-in-NFs were examined in vitro to evaluate the system's potential to be used in the treatment of skin wounds. Experimental results indicated that the novel NM-in-NF system had dual controlled release effect, which greatly reduced burst release and prolonged effective drug duration. Moreover, NM-in-NFs was also found to be safe and non-toxic, with a broad-spectrum antibacterial activity. It thus could potentially be used in long-term antibacterial medical dressings to treat skin wounds.