A self-driven PET chip-based imprinted electrochemical sensor for the fast detection of Salmonella

Abstract

A portable imprinted electrochemical sensor with a self-driven polyethylene terephthalate (PET) chip was developed for the fast detection of Salmonella. A chip with a siphon inlet connecting the reaction chamber and a capillary connecting the reaction chamber to the press chamber was innovatively designed to achieve self-drive. Based on siphonage and hydrophilicity, the liquid entered the reaction chamber automatically, and quantitative sampling was completed when the liquid reached the capillary. Waste liquid was discharged from the reaction chamber by pressing the press chamber. The self-driven PET electrode chip was prepared by screen-printing and laser-cutting, and Salmonella-imprinted film was then prepared on the chip working electrode via electropolymerization. Characterization studies of the modification of the working electrode were then carried out via SEM, AFM, water contact angle and electrochemistry. The detection of Salmonella was performed by differential pulse voltammetry within the range of 3.0 × 102 to 3.0 × 107 CFU mL−1, and the limit of detection was 100 CFU mL−1 (S/N = 3). The selectivity of the proposed sensor was then examined via the use of interfering bacteria, including E. coli, L. monocytogenes, and P. aeruginosa. The practical application value of the sensor was demonstrated by a recovery rate of 92–109% and a relative standard deviation of less than 2.96% in the detection of Salmonella in milk and orange juice samples. In summary, a self-driven PET chip-based imprinted electrochemical sensor for the detection of Salmonella within 20 min was developed, and has the potential to monitor and quickly control Salmonella contamination in food processing and food circulation.