An electrochemical sensor based on MnO2/ZnO composites for the detection of ciprofloxacin in honey

Long-term consumption of honey containing ciprofloxacin (CIP) residues may harm human health. It is important to establish a sensitive and rapid CIP detection method. This study reports for the first time the development of an electrochemical sensor for rapid determination of CIP in honey, utilizing a MnO2/ZnO composites. Two types of ZnO with different morphologies were prepared, characterized, and compared for their electrocatalytic properties for CIP. The findings indicated that the rod-like ZnO had a better catalytic effect on CIP and was thus selected to combine with MnO2 to form the composite material. Characterization of the resulting composite material was conducted, followed by an investigation of the electrochemical reaction of CIP on the electrode and optimization of the detection conditions of the sensors. The results indicate that the current value of CIP had a linear relationship with its concentration within the range of 0.5 to 120 µM, and the detection limit was 0.21 µM. The MnO2/ZnO/GCE sensor was applied to detect the CIP residues in honey samples, and the recoveries ranged from 95.3% to 97.2%. The results show that the composite material-modified sensor has good sensitivity and can enable rapid detection of CIP content in honey. Therefore, it has a potential application in detecting CIP residues in honey.