Rapid detection of P-35S and T-nos in genetically modified organisms by recombinase polymerase amplification combined with a lateral flow strip

Recombinase polymerase amplification (RPA) was first reported in 2006 and has recently been shown to improve the detection of genetically modified organisms (GMOs). This study developed a more efficient RPA-based and lateral flow test strip (LFD)-based platform for the detection of P-35S and T-nos for GMOs, circumventing the need for expensive instruments and technicians. Other methods were compared to our assay. The RPA forward and reverse primers were labeled with the fluorophore biotin, digoxin, and FITC at the 5' end and quickly determined whether the sample contains P-35S and T-nos of GMOs using the RPA-LFD method at room temperature. Nine events of GMOs were collected to determine the specificity of the RPA-LFD method, including KMD1, MON531, Rf1, Kefeng6, RRS, Bt11, MON863, Bt176, and Ms1. The results showed that the limit of detection of RPA-LFD was 50 copies and 100 copies, which was consistent with the limit of detection of RPA-AGE. The specificity and stability among the nine events were consistent, respectively. Finally, the perfect fitness for the detection of the nine double-blind samples indicated that the detection method is practical. In conclusion, we developed a more sensitive, specific, and stable field screening method for determining the GMO content with large-scale field applications.