Development of a visual RAA-LFA Sensor platform for detection of Vibrio cholerae via the OmpW gene

Vibrio cholerae is an important foodborne pathogen that causes severe diarrhea and poses a serious threat to public health. In this study, we developed a novel visual biosensor platform that integrates recombinase-aided amplification (RAA) with lateral flow assay (LFA) technology for the rapid and sensitive detection of the Vibrio cholerae outer membrane protein W (OmpW) gene. The system used multiple phosphorylated primers in the RAA reaction to generate DNA amplicons of different lengths. Subsequently, the amplification products were treated with λ exonuclease, and the resulting single-stranded DNA fragments were hybridized with FAM- and biotin-labeled probes immobilized prior to LFA detection, producing a visible colorimetric signal. The proposed assay achieved a detection limit of 57.2 CFU/mL. Compared to conventional methods, the proposed sensor platform offers several advantages, including rapid detection, the elimination of thermal cycling, and operational simplicity, making it suitable for rapid and specific detection of V. cholerae in resource-limited settings.