THE ANTIBACTERIAL ACTIVITY OF GUM ARABIC-COATED Mn-DOPED CuS NANOPRISMS

Novel nanoprism-shaped manganese-doped copper sulfide (Mn-CuS) was fabricated by two-phase colloidal method (Mn percentages = 0%, 1%, 3%, and 5%). The Mn-CuS was analyzed by XRD, FTIR, UV-Vis spectrometer, and TEM. The XRD shows that the hexagonal covellite copper sulfide peaks appeared at 2 theta=47.9 degrees,31.9 degrees,47.8 degrees, and 31.8 degrees for 0%, 1%, 3%, and 5% respectively, and orthorhombic chalcocite copper sulfide appeared at the peaks that are corresponding the planes (412), (275), (029) and (106). According to UV-Vis analysis, the optical absorption of manganese-doped copper sulfide 0%, 1%, 3%, and 5% clearly appeared in the UV-Vis region at 518, 440, 478, and 477nm respectively, and there are broad peaks for localized surface plasmon resonances (LSPR) of CuS located at 970, 1061, 1002, and 1006nm for Mn-CuS 0%, 1%, 3%, and 5%, respectively. The favored nanoprism-shaped sample (manganese-doped copper sulfide 1%) was coated with gum Arabic (GA) in order to decrease the cytotoxicity and enhance the biocompatibility. The antibacterial activity of manganese-doped copper sulfide and GA@Mn-CuS 1% nanostructure toward Staphylococcus aureus and Escherichia coli bacteria was determined by inhibition zone. It was found that the fabrecated Mn-CuS 1% nanoprisms were more active toward both E. coli and S. aureus bacteria and the doping enhanced the antibacterial activity.