Ultra-sensitive, high-throughput detection of infectious diarrheal diseases by portable chemiluminescence imaging

This paper describes a rapid, ultra-sensitive, and high-throughput pathogenic DNA identification strategy for infectious diarrheal diseases diagnosis. This strategy is based on specific DNA hybridization and horseradish-peroxidase-catalyzed chemiluminescence (CL) detection. Probe DNA strands are covalently immobilized on the aldehyde-group-modified slide and hybridized with biotin-modified target DNA strands. Horseradish-peroxidase (HRP) is then combined with the target DNA via a biotin-streptavidin linkage. The subsequently added mixture of luminol and hydrogen peroxide is catalyzed by HRP and radiates photons. The photons are collected and read out by a portable imager. The specific detection of target DNA strands was realized at a detection limitation of about 0.75nM. This strategy facilitates quantitative detection, as indicated by the fact that the CL signals were consistent well with a linear function. This method was applied to identify a myriad of real diarrheal pathogens samples, including Enterohemorrhagic Escherichia coli (EHEC), Vibrio cholerae (VBC), Shigella (SHLA), and Salmonella (SMLA). Triple-assay of six gene sequences from these pathogens was realized, which facilitates accurate, high-throughput identification of diarrheal pathogens. This CL assay strategy is appropriate for application in disease diagnosis and prevention. •An ultra-sensitive and high-specific DNA detection method was developed for infectious diarrheal diseases diagnosis.•This method is high-throughput based on the microarrays that covalently immobilized on the slide.•The CL signals were consistent well with a linear function, facilitating the quantitative detection.•Multiplex PCR product was used in the diagnosis to save the time and cost.•A portable and cost-effective chemiluminescence imager was developed for point-of-care diagnosis.