Detection of Salmonella by Surface Plasmon Resonance

This study explores the possibility of simultaneous and specific detection ofSalmonella serovars by surface plasmon resonance (SPR). The Plasmonic？ SPR device wasused to develop this rapid assay. The sandwich immunoassay involves the use of apolyclonal anti-Salmonella antibody to simultaneous capture multiple Salmonella serovarspresent in a sample. This is followed by specific detection of the captured serovars usingO-specific anti-Salmonella antibodies. Milk spiked with Salmonella Typhimurium andSalmonella Enteritidis was used as a model system to establish the assay. The assay wasfurther extended to sequentially differentiate between the two Salmonella serovars on asingle SPR chip in a single channel. The assay was proved to work without any additionaldilution or clean-up steps. The sample volume requirement for the assay is only 10 μL. Thelower limits of detection for Salmonella Typhimurium and Salmonella Enteritidis were2.50×105 cells mL-1 and 2.50×108 cells mL-1, respectively.