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Updated: Aug 20, 2026

Combination of Adhesive-tape-based Sampling and Fluorescence in situ Hybridization for Rapid Detection of Salmonella on Fresh Produce
Published on: October 18, 2010
[Detection of the Salmonella invasion gene invA using molecular beacon probe]
Cheng-song Wan1, Jun-ai Li, Jun Luo
1Department of Microbiology, Southern Medical University, Guangzhou 510515, China. gzwcs@fimmu.com
Objective:
To detect Salmonella invasion gene invA.
Methods:
The invA gene of Salmonella was amplified with PCR reaction system containing the molecular beacon probe labeled with 6-carboxy fluorescein (6-FAM) at its 5' end and with (4-dimethylaminophenylazo)benzoic acid (DABCYL) at its 3' end, and the fluorescence signal was read at the end of PCR.
Results:
The fluorescence values of S.enteritidis, S. paratyphi A, S. paratyphi B, S.typhi antigen H, S.typhi, and enteroinvasive E.coli were 161.6, 104.5, 85.9, 83.1, 94.8 and 46.1 respectively. The results of PCR of Salmonella was consistent with that of agarose gel electrophoresis.
Conclusion:
PCR with fluorogenic molecular beacon probe is rapid, specific, sensitive, and convenient for detecting Salmonella with invA gene.
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