Gold nanoparticles-based colorimetric assay for rapid detection of Salmonella species in food samples
ABSTRACT A rapid, sensitive and cost-effective method was developed for detection of foodborne pathogens, particularly Salmonella species. The method utilizes single stranded DNA (ssDNA) probes and non-functionalized gold nanoparticles to provide a colorimetric
assay for the detection of PCR amplified DNA. Different food samples were tested with the PCR-based colorimetric assay parallel
with the conventional culture method. The sensitivity and specificity of colorimetric assay was 89.15 and 99.04% respectively
with reference to conventional culture method. The total time required to detect the Salmonella spp. present in food samples by the developed method is less than 8h, including 6h incubation. It was observed that the
colorimetric assay was 10 times more sensitive than gel-based detection with the same concentration of DNA used for analysis.