Detection of Salmonella by Surface Plasmon Resonance

Abstract

This study explores the possibility of simultaneous and specific detection of Salmonella serovars by surface plasmon resonance (SPR). The Plasmonic ® SPR device was used to develop this rapid assay. The sandwich immunoassay involves the use of a polyclonal anti-Salmonella antibody to simultaneous capture multiple Salmonella serovars present in a sample. This is followed by specific detection of the captured serovars using O-specific anti-Salmonella antibodies. Milk spiked with Salmonella Typhimurium and Salmonella Enteritidis was used as a model system to establish the assay. The assay was further extended to sequentially differentiate between the two Salmonella serovars on a single SPR chip in a single channel. The assay was proved to work without any additional dilution or clean-up steps. The sample volume requirement for the assay is only 10 µL. The lower limits of detection for Salmonella Typhimurium and Salmonella Enteritidis were 2.50×10 5 cells mL -1 and 2.50×10 8 cells mL -1 , respectively.

Antibody-Based Sensors: Principles, Problems and Potential for Detection of Pathogens and Associated Toxins

“…Capture formats are typically used, involving the immobilisation of an antibody and the subsequent capture of a cell and, if deemed necessary, the addition of secondary antibody to enhance sensitivity [89,101,102]. In Biacore-based analytical systems, the depth at which a SPR-produced evanescent wave can penetrate when TIR occurs is 0.3 μm [28,101].…”

Visualization of submicron Si-rods by SPR-enhanced total internal reflection microscopy

“…This method can find applications in biosensor technology for detection of trace amounts of infectious microorganisms in various media. Feasibility of pathogens detection with the SPRbased biosensors has already been demonstrated [28][29][30][31]. The image quality obtained with the SPR-enhanced TIRM was sufficient for counting the scattering particles of submicron size.…”

Biosensor for detection of bacteria with probiotic potential and food pathogens

“…The assay can be carried out in a competitive mode. High-density particles are having a diameter in the range of 5-100 nm may be suitable [70,71].…”