Influence of curcumin-modified graphene oxide on antibacterial properties of polyurethane coating

This study aims to prepare antibacterial coatings based on polyurethane and curcumin-modified graphene oxide. Curcumin-modified graphene oxide (GO-CU) as an antibacterial agent was prepared using the adsorption method. GO-CU was incorporated in polyurethane (PU) coatings at concentrations of 0.1 and 0.5 wt%. Synthesized GO-CU was characterized by Fourier transform infrared spectroscopy, UV–Vis spectroscopy, transmission scanning electron microscopy, and zeta potential measurement. Curcumin content in GO-CU was determined by thermogravimetric analysis. Antibacterial properties of GO-CU powder and PU coatings containing GO-CU were investigated by counting the colony-forming unit (CFU) of Escherichia coli (E. coli) strain. The results showed that curcumin was attached on GO-CU surface and curcumin content in GO-CU was about 32.9%. GO-CU provided a higher antibacterial effect against E. coli than GO. The antibacterial efficiency of PU coatings containing 0.1 wt% GO-CU was 85.8%; however, the increase in GO-CU concentration did not significantly increase the antibacterial efficiency of PU coating.