Rapid and simultaneous detection of Campylobacter spp. and Salmonella spp. in chicken samples by duplex loop-mediated isothermal amplification coupled with a lateral flow biosensor assay

PLoS One. 2021 Jul 1;16(7):e0254029. doi: 10.1371/journal.pone.0254029. eCollection 2021.

Abstract

Development of a simple, rapid and specific assay for the simultaneous detection of Campylobacter spp. and Salmonella spp. based on duplex loop-mediated isothermal amplification (d-LAMP), combined with lateral-flow biosensor (LFB) is reported herein. LAMP amplicons of both pathogens were simultaneously amplified and specifically differentiated by LFB. The specificity of the d-LAMP-LFB was evaluated using a set of 68 target and 12 non-target strains, showing 100% inclusivity and exclusivity. The assay can simultaneously detect Campylobacter and Salmonella strains as low as 1 ng and 100 pg genomic DNA per reaction, respectively. The lowest inoculated detection limits for Campylobacter and Salmonella species in artificially contaminated chicken meat samples were 103 CFU and 1 CFU per 25 grams, respectively, after enrichment for 24 h. Furthermore, compared to culture-based methods using field chicken meat samples, the sensitivity, specificity and accuracy of d-LAMP- LFB were 95.6% (95% CI, 78.0%-99.8%), 71.4% (95% CI, 29.0%-96.3%) and 90.0% (95% CI, 73.4%-97.8%), respectively. The developed d-LAMP-LFB assay herein shows great potentials for the simultaneous detection of the Campylobacter and Salmonella spp. and poses a promising alternative approach for detection of both pathogens with applications in food products.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Biosensing Techniques / standards
  • Campylobacter / genetics
  • Campylobacter / isolation & purification*
  • Campylobacter / pathogenicity
  • Chickens / microbiology*
  • Food Analysis
  • Food Microbiology
  • Humans
  • Limit of Detection
  • Molecular Diagnostic Techniques*
  • Nucleic Acid Amplification Techniques*
  • Salmonella / genetics
  • Salmonella / isolation & purification*
  • Salmonella / pathogenicity

Supplementary concepts

  • LAMP assay

Grants and funding

This study was supported by the International Research Network (IRN) under The Thailand Research Fund (TRF) [grant numbers IRN59W0007]. TS received a research assistantship scholarship from the Faculty of Graduate Studies, Mahidol University, Academic Year 2018.