Facile fabrication of gelatin and polycaprolactone based bilayered membranes via spin coating method with antibacterial and cyto-compatible properties.

A growth of bacterial infections and over-and inefficient release of antibiotics forces one to search new antibacterial agents and/or strategies. In this study, a novel strategy towards biocompatible and antibacterial bilayer wound dressing was proposed by a two-step spin coating method combined with in-situ crosslinking polymerization. First, through in-situ crosslinking polymerization, [2-(methacryloyloxy) ethyl] trimethylammonium chloride ([MTA][Cl]) was polymerized and crosslinked in polycaprolactone (PCL) solution and PCL/PMTA solution was obtained. Then, the PCL/PMTA solution was spinning-coated as the antibacterial top layer and the mixture of PCL and gelatin (Gel) (PCL/Gel) as the biocompatible bottom layer. The obvious bi-layered structure and boundary between the two layers was distinctly showed in scanning electron microscope (SEM) pictures. X-ray diffraction (XRD), attenuated total reflection flourier transformed infrared spectroscopy (ATR-FTIR), differential scanning calorimeter (DSC), thermo-gravimetric analysis (TGA) and water contact angle (WCA) analysis were used to investigate the physical and chemical properties and obtained results demonstrated the successful preparation of the bi-layered membranes. The prepared bi-layered wound dressing displayed both strong antibacterial activity and good biocompatibility in vitro. The bilayered membranes with biocompatible and antibacterial properties would be next generation of wound dressing.