Multipurpose polyurethane antimicrobial metal composite films via wet cast technology

We report on the preparation and characterization of polyurethane (PU) film containing metal particles and their antibacterial activity. The utilized PU films containing metal particles were prepared by a simple solvent evaporation method. The surface morphology, structure and optical properties of the resultant products were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy and UV-vis spectroscopy. The antibacterial activity was tested against four common food borne pathogenic bacteria, namely, Staphylococcus aureus, Escherichia coli, Salmonella typhimurium, and Klebsiella pneumoniae by minimum inhibitory concentration (MIC) method. Our results demonstrated that no bactericidal activity was detected for the pristine PU film. Further on, antibacterial activity was observed to be more pronounced for the PU films containing metal particles which were attributed to the presence of metal in the PU thin films. Overall, this study demonstrates the fabrication of cheap, stable and effective material with excellent antimicrobial activity that can be utilized to inhibit the microbial growth associated with food stuff.