Zn DOPED CuO NANOPARTICLES BASED SURFACES AND COMPOUNDS EXHIBIT ENHANCED ANTIBACTERIAL AND ANTIBIOFILM ACTIVITY

Increase in nosocomial infections and bacterial antibiotic resistance raises major concerns world-wide. Many of the hard to treat infections involve biofilm and this raises the need for innovative solutions. In the current study, Zn-CuO (Zn_0.12Cu_0.88O) nanoparticles (NPs) compounds and surfaces were examined for their antibacterial and antibiofilm properties. These included (i) topical ointment, (ii) coated urinary catheters and (iii) a water-soluble PEGylated nano-graphene-oxide formulation to increase the dispersion of the Zn-CuO NPs. The NPs based ointment was able to effectively reduce biofilm formation as well as eradicate existing biofilm. As for the urinary catheters, the NPs were coated on the catheter surface using a sonochemical method. The coated catheters displayed promising biocompatibility as assessed in vitro by low cytotoxicity, negligible associated cytokine secretion and no detectable irritation. The Zn-CuO coated catheters were found to display high antibiofilm activity in an in vitro flow model and in vivo using a rabbit model. Rabbits catheterized with uncoated catheters scored positive for Catheter Associated Urinary Tract Infections (CAUTI) by the fourth day while rabbits catheterized with Zn-CuO coated catheters did not exhibit CAUTI or remained completely uninfected for the whole duration of the 7-day experiment. The rabbit in vivo assay biocompatibility assays also supported the biosafety of the ZnCuO NPs. Finally, we deposit the insoluble ZnCuO on NGO-PEG sheets to generate the NGO-PEG-ZnCuO novel complex, thus increasing their solubility and bioavailability. The soluble NGO-PEG-ZnCuO complex displayed high antibacterial activity with no cytotoxicity. Taken together, these data highlight the potential of Zn-doped CuO nanocomposites to serve as an effective antibacterial and antibiofilm compound for a range of medical applications.