Rapid and sensitive detection of Salmonella in milk based on hybridization chain reaction and graphene oxide fluorescence platform

ABSTRACT Salmonella is a foodborne pathogen that has contributed to numerous food safety accidents worldwide, making it necessary detect contamination at an early stage. A pair of specific primers based on the invA gene was designed for PCR. Target double-stranded DNA (dsDNA) from PCR purified and denatured high temperature obtain target single-stranded (ssDNA). Two carboxyfluorescein-labeled hairpin probes (H1-FAM H2-FAM) were with complementary portions ssDNA sequence so binding could trigger H1-FAM H2-FAM hybridization chain reaction (HCR) produce long dsDNA complex. In this study, graphene oxide (GO) used in development homogeneous fluorescence detection platform Salmonella. Using HCR-GO assay platform, completed 3.5 h. reliably specifically detected limit (LOD) 4.2 × 101 cfu/mL pure culture. Moreover, new successfully applied artificially contaminated milk LOD 102 cfu/mL.