Dual response mimetic enzyme of novel Co₄S₃/Co₃O₄ composite nanotube for antibacterial application

Novel Co₄S₃/Co₃O₄ composite nanotubes were first time successfully synthesized through the control of Na₂S treatment of Co(CO₃)_0.35Cl_0.20(OH)_1.10 precursor and testified to having both oxidase-like and peroxidase-like catalytic activities. Through nanoscale Kirkendall effect, acicular precursor was vulcanized to form Co₄S₃/Co₃O₄ nanotubes (NTs). Co₄S₃/Co₃O₄ NTs exhibit great properties such as smaller K_m and higher V_max than natural horseradish peroxidase, favorable selectivity and ideal stability. Co₄S₃/Co₃O₄ NTs with promising biocompatibility can realize spectral sterilization towards Escherichia coli and Staphylococcus sciuri in the presence of low level H₂O₂. It turned to be that superoxide anion radical catalyzed by Co₄S₃/Co₃O₄ NTs not only oxidizes 3, 3', 5, 5'-tetramethylbenzidine in the catalytic process but also eliminates gram-bacteria during sterilization. The successful synthesis of biofunctional Co₄S₃/Co₃O₄ NTs can serve as significant applications of new energy and environmental catalysis.