Development of a Surface Plasmon Resonance Biosensor for the Indentification of Campylobacter jejuni

Abstract

Bacteria are the most common foodborne pathogens, which can cause common, distressing, sometimes life-threatening foodborne diseases to any human around the world, especially elderly, debilitated, compromised people (cancer, AIDS, and transplant patients) and infants. Therefore, rapid, specific, and sensitive routine monitoring and reliable detection and identification for bacterial pathogens are necessary in order to reduce their impacts upon human health. Campylobacter is one of the most common foodborne pathogens, which can cause acute bacterial enteritis in humans throughout the world. The purpose of this study was to examine the sensitivity and specificity of commercial antibodies against C. jejuni for the development of a biosensor based on surface plasmon resonance. Six Campylobacter strains and six non-Campylobacter bacterial strains were tested for reactivity with the antibodies. Antigen-antibody interactions were studied using enzyme-linked immunosorbent assay (ELISA) and a commercially available surface plasmon resonance (SPR) biosensor platform (Spreeta™). The reactivity to antibody of Campylobacter cells kept in phosphate buffer solution at 4 °C for up to 24 days were similar to the reactivity of 24-h-cultured cells. Campylobacter cells killed with 0.5% formalin had significant lower antibody binding reactivity when compared to live cells, or cells inactivated with 0.5% thimerosal or heat (70 °C for 3 min). The SPR biosensor showed low reactivity with Salmonella serotype Typhimurium and a sensitivity of 103 CFU of C. jejuni per ml. Although the average assay time was 45 min, this time could be easily shortened to an assay time of no more than 30 min. The sensitivity and specificity of SPR biosensor could be enhanced by incorporating a DNA-DNA biorecognition. This SPR biosensor could be further developed for rapid identification of C. jejuni in broiler products.