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Synthesis of Functionalized Magnetic Nanoparticles, Their Conjugation with the Siderophore Feroxamine and its Evaluation for Bacteria Detection
Published on: June 16, 2020
Multicolor colorimetric visual detection of Staphylococcus aureus based on Fe3O4-Ag-MnO2 composites nano-oxidative
Yushen Liu1, Mengyue Sun2, Wenteng Qiao2
1College of Food Engineering, Ludong University, Yantai, 264025, Shandong, China; Bio-Nanotechnology Research Institute, Ludong University, Yantai, 264025, Shandong, China.
Abstract:
Novel Fe3O4-Ag-MnO2 composites were successfully synthesized. It was noteworthy that the obtained Fe3O4-Ag-MnO2 composites were found to possess three types of enzyme-mimicking activities, including peroxidase-like, catalase-like and oxidase-like activities. Taking advantage of the oxidase properties of Fe3O4-Ag-MnO2, the direct oxidation of TMB could be catalyzed to generate blue oxidation products without H2O2. The oxidase-like activity of Fe3O4-Ag-MnO2 were carefully studied. Based on the Fe3O4-Ag-MnO2-TMB system, a fast, sensitive and intuitive multicolor colorimetric method for Staphylococcus aureus (S. aureus) detection was established under the optimized conditions. The proposed method allows the detection of S. aureus with a detection limit of 3.7 cfu mL-1 and a linear range of 10-106 cfu mL-1. This new colorimetric method has been successfully proved to be applicable to the detection S. aureus of food samples.

