A new method for rapid, portable, low-cost detection of Clostridium perfringens β2 toxin in animal fecal using smartphone-based electrochemical immunosensor

Clostridium perfringens (Cp) β2 toxin poses a significant threat to the breeding industry because of its potential to cause enterotoxaemia in livestock. However, existing quantitative methods are very scarce. Thus, we developed a rapid, portable, low-cost quantitative detection method for Cp β2 toxin using a smartphone-based electrochemical immunosensor. Recombinant 32a-β2 toxin protein was successfully prepared as an antigen, as well as its monoclonal antibody. As an alternative to the traditional three-electrode system, a ternary nanocomposite-modified commercially integrated three-electrode chip was fabricated. A smartphone-based electrochemical immunosensor was constructed by combining a low-cost handheld potentiostat with a smartphone, and it was compared with a large-scale potentiostat. Under optimal conditions, the portable sensor for identifying Cp β2 strain expression displayed a linear relationship from 0.1 to 100 ng mL−1, a low detection limit of 16.45 pg mL−1, high sensitivity, a low cost, easy operation, outdoor rapid detection, and satisfactory practicability and reliability.