Abstract:[Objective] A simple and sensitive detection method for Staphylococcus aureus is established for the efficient detection of this pathogen in food.[Method] Targeting Staphylococcus aureus, a simple and sensitive fluorescent detection method for Staphylococcus aureus, EXPAR-P-AgNCs, was developed based on exponential amplification reaction (EXPAR) combined with DNA silver nanoclusters (P-AgNCs). A recognition probe was designed to initiate EXPAR in the presence of Staphylococcus aureus, generating a large amount of target DNA(T). The binding of T to hairpin P displaced the G-rich strand from P-AgNCs, resulting in a decrease in the relative fluorescence intensity of P-AgNCs and enabling the detection of Staphylococcus aureus.[Result] The relative fluorescence intensity showed a good linear relationship with Staphylococcus aureus concentration in the range of 1×102 and 1×10? CFU/mL. The limit of detection was as low as 10 CFU/mL. The method shows high specificity without cross-reactions. The recovery rates for Staphylococcus aureus spiked in milk and pork samples ranged from 94.5% to 115.0%.[Conclusion] The developed detection method demonstrates high sensitivity and excellent specificity, offering a promising approach for the detection of microbial pathogens or other contaminants threatening food safety.
