| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 867056 | Biosensors and Bioelectronics | 2013 | 7 Pages |
Sensitive and rapid detection of Salmonella is a key to the prevention and identification of problems associated with human health and safety. Enzyme Linked Immunosorbent Assays (ELISAs) are popular and widely implemented technique to detect pathogenic bacteria in routine analysis but a typical ELISA yields a sensitivity of 106–107 cfu/mL. The present study consecrates on the applicability of surface modified polyacrylonitrile (PAN) fibers as a novel matrix of immunoassay for the detection of Salmonella typhimurium in a sandwich ELISA format. Affinity purified antibody against Salmonella common structural antigen (CSA-1-Ab) was immobilized on modified PAN (mPAN) fibers using covalent immobilization via amine–glutaraldehyde chemistry and inactivated S. typhimurium were captured from various samples and detected colorimetrically using peroxidase-labelled common structural antibody (CSA-1-Ab-HRP) against Salmonella. The performance of the developed immunoassay was compared with commercially available immunomagnetic microbeads (Dynabeads® anti-Salmonella), polystyrene (PS) microtitre plate and glutaraldehyde activated PS plate. Limit of detection (LOD) was found to be 10, 105, 106 and 107 cells/mL of bacteria for mPAN, Dynabeads®, glu-plate and PS plate respectively without any pre-enrichment step. The assay was specific for the targeted bacteria when investigated with other cross-reactant food and water-borne pathogens. The developed immunoassay offered undisputed advantages of being simple, sensitive and specific for the detection of S. typhimurium.
► Successful capturing of S. typhimurium on modified PAN fibers from various samples using sandwich ELISA. ► Developed immunoassay is very sensitive compared to conventional ELISA & Dynabeads®. ► Immunoassay is specific even in presence of co-contaminants E. coli and other cross-reactant microbes. ► mPAN based immunoassay shows good recovery and low intra and inter day coefficient of variation. ► Developed mPAN-ELISA is simple, time efficient, inexpensive and can be taken to the field condition.
