Rapid and Simple Detection of in Food Matrices Using RPA-CRISPR/Cas12a Method

Pathogenic variants of pose a serious threat to human health and food safety, but there is a lack of rapid and sensitive field detection methods for . In this study, the CRISPR/Cas12a system combined with recombinant enzyme polymerase amplification (RPA) was used to detect in food. The optimized RPA-CRISPR/Cas12a assay was able to specifically and stably detect at a constant 37 °C without the assistance of large equipment. The detection limit of the method was evaluated at two aspects, the genomic DNA (gDNA) level and bacterial quantity, of which there were 10 ng/μL and 10 CFU/mL, respectively. Three kinds of real food samples were tested. The detection limit for rice noodles, fresh white noodles, and glutinous rice flour samples was 10 CFU/mL, 10 CFU/mL, and 10 CFU/mL, respectively, without any enrichment steps. The whole detection process, including sample pretreatment and DNA extraction, did not exceed one hour. Compared with the qPCR method, the established RPA-CRISPR /Cas12a method was simpler and even more sensitive. Using this method, a visual detection of that is suitable for field detection can be achieved quickly and easily.