Waterborne pathogens (bacteria, virus, and protozoa) are significant contributors to the global health burden, resulting in an estimated 2.2 million deaths annually. Repeated disease outbreaks (
Escherichia Coli,
Campylobacter jejuni,
Salmonella,
Vibrio cholerae,
Giandia, etc.) emphasize the dire need for a rapid and inexpensive diagnostic tools for reliable and efficient countermeasures. Although water treatment must continue to be at the forefront of such a countermeasure, it is critical to develop portable and inexpensive systems that scale for widespread deployment and implementation to directly detect the pathogens at the water sources (especially in resource-limited areas). We report an inexpensive and portable smartphone-based fluorescence imaging system for rapid detection of water-borne pathogens via Loop-mediated isothermal amplification (LAMP) of specific nucleic acid targets in disposable microfluidic chips. The microfluidic chips are machined with a desktop CNC machine with several optically clear pockets to house water samples. A low powered thermal management system ensures uniform heating of the samples for 30 minutes after which the fluorescence signals of the amplified targets are quantified with a high degree of confidence using a chromaticity-luminance analysis
1 to determine the presence/absence of pathogenic genetic material. Such low cost integrated nucleic acid amplification and fluorescence imaging system has the potential to simultaneously detect multiple pathogenic microorganisms. When implemented on a larger scale, such a technology could provide quantitative microbial risk assessment that evaluates the location-based likelihood of pathogen contamination resulting in rapid and reliable decision-making around such scenarios.
(1) Priye, A.; Ball, C. S.; Meagher, R. J. Analytical chemistry 2018, 90, 12385-12389.
