A convenient electrochemical biosensor mediated by filtration-assisted pretreatment and multi-TEs amplification system for Staphylococcus aureus detection in complex matrices

Rapid detection of foodborne pathogens plays a more and more significant role in the field of public health. In this research, we developed a convenient electrochemical biosensor mediated by filtration-assisted pretreatment and multiple thermostatic enzymes (Multi-TEs) amplification system for the detection of Staphylococcus aureus (S. aureus) in complex matrices. Firstly, the designed filtration-assisted pretreatment could simultaneously collect and enrich target bacterium from various actual samples within 5 min. Then, the target bacterial genome template was reacted at 37 degrees C in Multi-TEs amplification system to obtain specific double stranded products. Finally, the specific double stranded products were fixed on the surface of the electrode and the electrochemical indicators (Methylene blue, MB) was combined for the quantitative one-step electrochemical analysis of S. aureus. This assay has great linear calibration curves with the concentration ranging from 101 CFU/mL to 106 CFU/mL. The limit of detections (LOD) was defined as 1.28 CFU/mL, which performance is superior to some commercial ELISA kits. Meanwhile, amazingly, it has excellent specificity for S. aureus against other foodborne pathogens and could be applied for S. aureus analysis in human serum samples with the great recoveries and associated relative standard deviations (RSDs). These features do make the ideal facile electrochemical analytical platform for on-site detection of S. aureus.