Ultrafast bacterial cell lysis using a handheld corona treater and loop-mediated isothermal amplification for rapid detection of foodborne pathogens

Abstract

Bacterial foodborne diseases have become a growing global health concern, and nucleic acid-based analysis is considered as a promising approach for rapid identification of foodborne pathogens. Accordingly, nucleic acid isolation becomes the prerequisite first step for subsequent bioanalysis. However, current nucleic acid extraction suffers from operation time delayed, amplification inhibited by chemicals, or bulky instruments required. Here, we presented an ultrafast bacterial cell lysis induced by corona discharge within 40 s and combined it with loop-mediated isothermal amplification (LAMP) for the first time to achieve rapid and convenient detection of foodborne pathogens. Firstly, the viability and morphological changes revealed that corona discharge could destabilize bacterial cell envelope and eliminate more than 90% of Salmonella enterica (S. enterica) or Staphylococcus aureus (S. aureus) within 40 s. More surprisingly, more DNA were released from 100-103 CFU of electrical lysed S. enterica than equivalent thermal lysed ones, manifesting advantages of corona discharge on shorter preparation time and greater yields of DNA. Furthermore, the advantages of this ultrafast bacterial cell lysis were leveraged when collaborating with colorimetric LAMP. After conducting colorimetric LAMP in a water bath at 63 °C for 1 h, we could visually detect released DNA from 100 CFU of electrical lysed S. enterica and 103 CFU of electrical lysed S. aureus, respectively. Finally, we validated the applicability of the electrical lysis combined with LAMP reaction to detect (viable) S. enterica and S. aureus in artificially spiked pork samples. Therefore, we provided a rapid and convenient bioanalysis platform integrating an ultrafast electrical lysis and LAMP detection, opening up its extensive applications for versatile pathogens in resource-limited settings.