On-Site Visualization and Sensing Platform for Detecting Genetically Modified Papaya "55-1" in Papaya-Derived Products.

Genetically modified (GM) papaya "55-1" is the world's first papaya cultivar resistant to Papaya ringspot virus (PRSV). To facilitate government regulation and protect consumers' rights to informed choices, scientists are expected to develop a rapid and straightforward method for detecting "55-1". In this study, we established an on-site visualization and sensing platform based on recombinase polymerase amplification (RPA) to detect "55-1" in papaya-derived products. Amplified signals were generated exclusively in samples containing "55-1", with a detection limit of 20 copies, demonstrating high specificity and sensitivity. The entire process was completed within 40-60 min, indicating high efficiency. The platform was successfully applied to detect "55-1" in papaya leaves and derived products, producing results consistent with those obtained via polymerase chain reaction (PCR) analysis. To the best of our knowledge, this is the first platform enabling on-site visual detection of "55-1", and it provides a technical reference for the rapid detection of other GM plants.