rapid detection of staphylococcus aureus via recombinase polymerase amplification combined with lateral flow strip

Food contamination caused by staphylococcus aureus is a major problem worldwide, and more accurate and sensitive methods suitable for field detection are vital for s. aureus surveillance and control. traditional methods for microbiological detection and identification are time-consuming and laborious. although polymerase chain reaction-based methods are effective, the need for sophisticated, expensive equipment, and trained personnel greatly limits their applicability in point-of-care detection. in the present study, a rapid and visual detection method based on the combination of recombinase polymerase amplification (rpa) and lateral flow (lf) strips was developed for the detection of s. aureus. dna products labeled with biotin and digoxin were produced by biotin-modified primers and a digoxin-modified probe, which was visualized on lf strips after interaction with gold nanoparticle-labeled anti-digoxin antibodies and capture by streptavidin. under optimal conditions of 10 min at 40 °c for rpa, followed by 5 min at room temperature for lf, this method could detect 500 fg genomic dna and 1.2 × 101 cfu/ml of s. aureus in pure culture. specificity analysis showed no cross-reaction with other pathogenic bacteria. in actual food samples, 1.2 cfu/ml (g) s. aureus could be detected in chicken breasts, pork, fish, beef, milk, evaporated milk after enrichment for 3 h, and in eggs after enrichment for 4 h. to our knowledge, the present study is the first report to employ rpa-lf to detect s. aureus and provides a potentially useful method for the rapid detection of s. aureus in food samples.