Sensitive and high‐accuracy detection of Salmonella based on CRISPR/Cas12a combined with recombinase polymerase amplification.

Salmonella is a crucial food‐borne pathogen causing food poisoning, leading to severe public health events. Here, we developed a technique by integrating recombinase polymerase amplification with CRISPR‐LbCas12a and employing two targets with engineered crRNA for detection of Salmonella (RPA‐LbCas12a‐TTECDS). Our findings revealed that this novel method rapidly detects trace Salmonella in food through fluorescence intensity and provides a template for other food‐borne pathogen detection methods. Further, crRNA was optimized to increase detection sensitivity. Double targets were used to enhance the detection accuracy, reaching the level of qPCR, which was superior to fluorescent RPA. The RPA‐LbCas12a‐TTECDS system specifically detected Salmonella levels as low as 50 CFU per ml at 37°C in 1 h. In summary, a simple, rapid, sensitive and high accuracy detection technique based on CRISPR‐Cas12a was created for Salmonella detection without complicated equipment. Significance and Impact of the Study: The emergence of CRISPR‐Cas12a provides a new technique for detection methods. In this study, we developed a rapid, sensitive, and high accuracy RPA‐LbCas12a‐TTECDS based toolbox for Salmonella detection. This method is easy to operate with a completion span of 50 min by a fluorescence detector. The simple and quick‐to‐read method is potentially useful as point‐of‐care testing for Salmonella. [ABSTRACT FROM AUTHOR]