Development and comparative study of rapid detection methods for Salmonella based on multiple molecular and immunological techniques

The detection of Salmonella in milk is critical for dairy safety, requiring rapid and sensitive methods. This study developed and compared three independent techniques: real-time PCR (qPCR), loop-mediated isothermal amplification (LAMP), and a gold immunochromatographic test strip (GICT), all targeting the invA gene. In artificially contaminated milk, qPCR achieved a detection limit of 10 3 CFU/mL with no cross-reactivity against non-target bacteria. LAMP amplification was completed within 30 min at 63°C, with detection limits of 4.17×10 3 CFU/mL (visual) and 4.17×10 2 CFU/mL (gel electrophoresis). The GICT strip, based on monoclonal antibody 8E7 1C8, showed a detection limit of 10 4 CFU/mL and remained stable for six months at 4°C. While qPCR and LAMP offered high sensitivity suitable for laboratory quantification, GICT provided a rapid, equipment-free option for on-site screening. Together, these methods provide a complementary toolkit for detecting Salmonella across laboratory and field settings.