Development of a DNA microarray-based method for detection on multiple water and foodborne pathogens
A microarray-based assay was developed and evaluated for simultaneous detection of multiple food and waterborne pathogens. Fifteen oligonucleotide probes and a multiplex PCR assay were developed based on genes of the parasites ' Cryptosporidium parvum, Giardia intestinalis' and ' Cyclospora cayetanensis'. The probes and PCR assay were combined with a previously developed PCR-microarray assay for detection of 'E. coli, Salmonella, Listeria' and 'Campylobacter'. The combined parasite and bacterial detection system was tested for specificity using 95 target and 56 nontarget strains. All strains produced the expected results. The system's detection limit for purified cells and water sediment samples was equivalent to 48 and 91 cells, respectively. Multiple pathogens were also correctly identified in 30 spiked water sediment samples. It was concluded that the microarray system provided rapid and reliable detection of multiple pathogens in a single assay and should potentially be a valuable tool for comprehensive and cost-effective water and food safety testing.