Investigation On Electrochemical Sensing Based On Metal Oxide Composites

The combination of the characteristic metal oxide composites and the novel sensing principle for electrochemical sensor can significantly improve the analytical performance of electrochemical sensing.Herein,electrochemical sensing has a wide range of applications in food safety,environmental monitoring,biomedical and other fields.In this thesis,Ni Co₂O₄@Ni Co₂O₄ nanostructures and flower-like Zn O-Au composites have been synthesized through hydrothermal method,water bath method,etc.Based on the prepared materials,an electrochemical sensor and an aptasensor were successfully constructed for the detection of glucose and ochratoxin A(OTA)respectively.Ni Co₂O₄@Ni Co₂O₄ nanoarray exhibited efficient catalytic activity for glucose.The detection limit of the glucose sensor was 1.1×10^-3 m M.The aptasensor relied on Zn O-Au composites can detect OTA in the range of 0.1-3×10⁴ pg·m L^-1,and the detection limit is 5×10^-2 pg·m L^-1.These two sensors could be used to detect glucose and OTA in beverages.Compared with the same type of sensors,these two sensors have been further improved in terms of high sensitivity,high selectivity,wide linear range and high stability.This work provides the reference for the construction of high-performance sensing interface and the detection of disease markers and food contaminants.