A Sandwich-type Electrochemical Immunosensor for the Sensitive Determination of Salmonella Typhimurium in Food

A sandwich-type electrochemical immunosensor was developed for sensitive detection of Salmonella Typhimurium (S. Typhimurium) in milk and eggs. According to the antigen-antibody specific binding, Anti-S. Typhimurium antibody was used to recognize the S. Typhimurium, while the HRP-Anti-S. Typhimurium antibody as signal probe was used to catalyze H2O2 with the assistance of thionine. The immunosensor showed wide linear range from 5.6x10(1) to 5.6x10(8) CFU/mL and low detection limit of 35 CFU/mL. The immunosensor also exhibited excellent specificity, reproducibility and stability, indicating that it had practicability in quality control of complex food samples and potential in clinical applications.