Hydrothermal synthesis of cobalt-doped vanadium oxides: Antimicrobial activity study

Cobalt-doped vanadium oxide (CoVOx) nanocomposites were synthesized using facile hydrothermal sol-gel method. The final products were annealed at 500 °C in the furnace for 2 h under vacuum and air, which led to Co3(VO4)2, CoV2O6 and pure V2O5 powders respectively. The nanoparticles (NPs) were characterized by X-ray Diffraction and Scanning Electron Microscopy (SEM). The magnetization behavior of the samples shows step-like increase for CoV2O6 material while the magnetic moment is quasi saturated at 2 T for Co3(VO4)2.The antibacterial activity of CoVOx nanocomposites was tested against two gram negative and two gram positive bacterial isolates. The bacterial strains were treated with increasing concentrations of NPs (0-3.5 mg/ml) for 24 h. The cell viability was assessed using Alamar Blue assay to monitor the response and health of the cells in culture after treatment with various pathogens. Among the three NPs tested, Co3(VO4)2 and CoV2O6 showed enhanced anti-bacterial activity on the four isolates compared to V2O5 which manifests an activity on E.coli at the highest dosage.