Manganese Oxide Deposition on Defective Graphene Oxide Nanosheets for Enhanced Antibacterial Activity Under Monochromated Light
Physical and Biological Sciences
CHEM 199F
At least 2 million people suffer medical conditions related to antibiotic resistant bacteria each year in the United States. About 1% of the infected population have deceased in 2013 from bacteria with conferred resistance. The efficacy of antibiotics targeting resistant bacteria are defined by their structural integrity and genomic composition. Beta-lactam antibiotics target penicillin binding proteins (PBPs), which are a group of proteins responsible for the synthesis of the cell wall. Since resistance to antibiotics are defined mainly by PBPs, changing or increasing the target sites of the molecule will enhance its activity. Manganese dioxide is a useful alternative to beta-lactam antibiotics. The metal oxide is a semi-conducting material which produce reactive oxygen species (ROS) under a photodynamic process. ROS leads to antibacterial activity, which can be enhanced by utilizing Graphene Oxide Quantum Dots (GOQDs) as a substrate for manganese dioxide growth. The concentration of defects on GOQDs and manganese precursor can affect antibacterial efficacy by affecting the surface area of manganese dioxide. In this study, different percentages of Potassium Permanganate were utilized with constant concentrations of Graphene Oxide with similar defects to synthesize MnO2 deposited GOQDs via sol-gel method. Antibacterial activity was measured as a function of MnO2/GOQD concentration by colony forming units (CFU). Photoactivity was measured under a monochromated UV-lamp under various time points via CFU. Nucleation of the MnO2structures on GOQDs was measured by UV-VIS and photoluminescence spectroscopy.
