Integrated LAMP and immunoassay platform for diarrheal disease detection

Biosens Bioelectron. 2018 Nov 30:120:93-101. doi: 10.1016/j.bios.2018.08.005. Epub 2018 Aug 10.

Abstract

The challenges of diagnosing infectious disease, especially in the developing world, and the shortcomings of available instrumentation have exposed the need for portable, easy-to-use diagnostic tools capable of detecting the wide range of causative microbes while operating in low resource settings. We present a centrifugal microfluidic platform that combines ultrasensitive immunoassay and isothermal amplification-based screening for the orthogonal detection of both protein and nucleic acid targets at the point-of-care. A disposable disc with automatic aliquoting inlets is paired with a non-contact heating system and precise rotary control system to yield an easy-to-use, field-deployable platform with versatile screening capabilities. The detection of three enterotoxins (cholera toxin, Staphylococcal enterotoxin B, and Shiga-like toxin 1) and three enteric bacteria (C. jejuni, E. coli, and S. typhimurium) were performed independently and shown to be highly sensitive (limit of detection = 1.35-5.50 ng/mL for immunoassays and 1-30 cells for isothermal amplification), highly exclusive in the presence of non-specific targets, and capable of handling a complex sample matrix like stool. The full panel of toxins and bacteria were reliably detected simultaneously on a single disc at clinically relevant sample concentrations in less than an hour. The ability of our technology to detect multiple analyte types in parallel at the point-of-care can serve a variety of needs, from routine patient care to outbreak triage, in a variety of settings to reduce disease impact and expedite effective treatment.

Keywords: Centrifugal; Enteric pathogens; Immunoassay; Isothermal amplification; LAMP; Microfluidics; Point-of-care.

MeSH terms

  • Biosensing Techniques / instrumentation
  • Biosensing Techniques / methods*
  • Diarrhea / diagnosis*
  • Enterobacteriaceae / genetics
  • Enterobacteriaceae / physiology*
  • Enterotoxins / analysis*
  • Feces / chemistry
  • Feces / microbiology
  • Humans
  • Immunoassay*
  • Limit of Detection
  • Microfluidics
  • Nucleic Acid Amplification Techniques*

Substances

  • Enterotoxins