Electrochemical Biosensor Based on Hierarchical Nanoporous Composite Electrode for Detection of Oxytetracycline

A facile and sensitive electrochemical sensor based on hierarchical nanoporous Pd-HSiO1.5/Ni–Co composite electrode for detecting oxytetracycline (OTC) was prepared in this study through the composite electrodeposition method. Electrodeposition conditions and detecting parameters, such as concentration of hierarchical nanoporous Pd-HSiO1.5 particles, detection temperature and scanning rate were also studied. Moreover, the repeatability, accuracy and anti-interference performance of electrochemical biosensor were investigated. Results showed that the hierarchical nanoporous composite electrode had the optimum electrocatalytic activity for OTC when the concentration of hierarchical nanoporous Pd-HSiO1.5 particles was 2 g/L and detection temperature was 25 °C. In addition, the electrochemical biosensor showed good electrocatalytic activity for OTC detection, with a linear relationship between oxidation peak current and concentration of OTC detection from 4.0 × 10–4 to 1.0 × 10–8 M. The limit of detection was as low as 1.0 × 10–8 M. Moreover, practical operations showed that the biosensor had good reproducibility, accuracy, and good anti-interference performance for other antibiotics such as ampicillin sodium and rifampicin.