An ultrasensitive bacterial imprinted electrochemical sensor for the determination of Lactobacillus rhamnosus GG.

An ultrasensitive label-free electrochemical sensor based on a homemade imprinted polypyrrole (PPy) polymer film was prepared to achieve quantitative determination of Lactobacillus rhamnosus GG (LGG). The LGG-imprinted polymer (LIP) film was deposited on a portable screen-printed electrode (SPE) via electropolymerization, which constituted an independent integrated system. The main preparation parameters of the LIP sensor were investigated to obtain optimal performance. Under optimized conditions, the peak current response of the LIP sensor showed a linear relationship with the logarithmic value of LGG concentration in the range from 10 to 10 CFU mL and a detection limit of 5 CFU mL. The proposed LIP sensor has achieved efficient, ultrasensitive, highly selective, and cost-effective detection of LGG and can be further developed for practical applications in the quality inspection and development of probiotic products.