The detection of Salmonella using a combined immunomagnetic separation and ELISA end-detection procedure

Abstract

The aim of this study was to develop a rapid immunoassay to detect Salmonella bacteria. Skimmed milk powder (SMP) in buffered peptone water was inoculated with six Salmonella strains (Salm. typhimurium, Salm. virchow, Salm. enteritidis, Salm. give, Salm. ealing and Salm. arizonae) at three inoculum levels (about 2–200 cfu 25 g−1 SMP) and incubated (37 °C) overnight. Heat‐treated salmonella cells were immobilized on paramagnetic particles and detected within 3 h using the Salmonella genus‐specific monoclonal antibody M105 in a microtitre plate based assay. The rapid Salmonella detection method combining immunomagnetic separation and ELISA had a total isolation and detection time of less than 24 h, which is significantly shorter than the conventional techniques requiring 72–96 h. The technique had a sensitivity limit of 105−106 cfu ml−1.

Landscape phage probes for Salmonella typhimurium

“…typhimurium, requires probes that specifically bind biological agents and insure their separation, purification and detection (Mansfield and Forsythe, 2000;Petrenko and Sorokulova, 2004). These binding probes can be isolated from diverse peptide or antibody libraries using phage display (Petrenko and Vodyanoy, 2003).…”

“…Since then, numerous molecular recognition methods have been elaborated for detection of bacteria, most attempting to incorporate speed and simplicity (Madonna et al, 2001;Mansfield and Forsythe, 2000;Meckes and MacDonald, 2003), as reviewed in Petrenko and Sorokulova, 2004. Simplified, rapid identification is especially important for pathogenic food-borne bacteria.…”

Modified Bacteriophage S16 Long Tail Fiber Proteins for Rapid and Specific Immobilization and Detection of Salmonella Cells

“…The lowest initial contamination rate tested, i.e., 1 to 10 CFU per 25 g or ml, could be detected in chicken, infant formula, milk, and chocolate milk, meeting the required detection limit for Salmonella according to the methods of the USDA Microbiology Laboratory Guidebook (53) and the FDA Bacteriological Analytical Manual (54) and significantly reducing detection times, from 72 h to 24 h. HRP-conjugated LTF offers a rapid enzyme-linked sandwich detection assay. Colorimetric or fluorescent ELISA-based assays have been successfully combined with IMS for rapid identification and quantification of bacterial contaminations (12,14,15). We therefore assessed the functionality of the phage S16 LTF as a secondary probe to detect bead-bound Salmonella (Fig.…”

A DNA biosensor for molecular diagnosis of <i>Aeromonas hydrophila</i> using zinc sulfide nanospheres

“…Aeromonas hydrophila is transmitted to fish through contaminated water or infected animals, and this bacterium may also cause some human diseases such as gastroenteritis and diarrhoea (Blake et al, 1980;Daskalov, 2006;Ljungh et al, 1977). Many different methods have been used for detection and determination of pathogenic bacteria, including solid and aqueous culture media (Kiyohara et al, 1982;Xie et al, 2005), gram stain (Nugent et al, 1991), biochemical studies (coagulase, oxidase, and catalase) (Hjelm et al, 2004;Raus and Love, 1983;Sumner and Taylor, 1989), impedance measurement (Suehiro et al, 2003), flow cytometry (Gunasekera et al, 2000), adenosine triphosphate (ATP) assessment (Chen and Godwin, 2006), polymerase chain reaction (PCR) (Belgrader et al, 1999), enzyme-linked immunosorbent assay (ELISA), and other novel techniques (Mansfield and Forsythe, 2000;Ruzicka et al, 2016). All conventional methods have at least one of these disadvantages: low detection accuracy, long time of detection, and the high detection cost (de Boer and Beumer, 1999;Gunasekera et al, 2000;Jorgensen and Turnidge, 2015;Megraud, 1996).…”