Rapid detection of Salmonella and Staphylococcus aureus using a hand-held nucleic acid detection system

Salmonella and Staphylococcus aureus are common pathogens that cause foodborne illnesses. Currently, the detection of these pathogens involves time-consuming procedures, namely isolation, cultivation, and biochemical identification, making it impossible for on-site real-time testing. In this study, we developed a compact hand-held real-time fluorescent nucleic acid testing device and specific lyophilized reagents to achieve rapid detection of Salmonella and S. aureus within 30 min. The detection sensitivity was 100 colony-forming units (CFU)/mL for Salmonella and 125 CFU/mL for S. aureus. This technique significantly reduced the detection time compared with the traditional cultivation method. Even at low initial concentrations of 5 CFU/mL for Salmonella and 15 CFU/mL for S. aureus, it demonstrated superior performance compared with traditional cultivation, detecting the target bacteria more than 2 days earlier than that method. Notably, we achieved 100% in the detection of Salmonella and S. aureus using spiked pastry samples. In addition, the proposed detection system exhibited excellent specificity when tested against 27 bacterial strains. In conclusion, the proposed nucleic acid detection system provides a viable, miniaturized solution for rapid detection of bacteria.