Establishment of a Method Combined Immunomagnetic Separation with Colloidal Gold Lateral Flow Assay and Its Application in Rapid Detection of Escherichia. coli O157：H7

• Published in: Fēnxī huàxué Vol. 41; no. 12; pp. 1812 - 1816
• Main Authors: CUI, Xi, XIONG, Qi-Rong, XIONG, Yong-Hua, SHAN, Shan, LAI, Wei-Hua
• Format: Journal Article
• Language: English
• Published: 01.01.2013
• Subjects: Antibodies; Assaying; Beads; Colloids; Escherichia coli; Foods; Gold; Monoclonal antibodies; Separation
• ISSN: 0253-3820
• DOI: 10.3724/SP.J.1096.2013.30494

The immunomagnetic beads were prepared by coupling anti-Escherichia, coli O157:H7 monoclonal antibody with magnetic beads. The colloidal gold test strip was composited with anti-O157:H7 monoclonal antibody marked by colloidal gold as the detection antibody, anti-E. coli O157:H7 polyclonal antibody as the test line and the donkey anti-mouse IgG secondary antibody as the control line. Immunomagnetic separation was combined with colloidal gold lateral flow assay, and this method was applied in the rapid detection of E. coli O157:H7. The results showed that 1 mL of 7.6x10 super(3) CFU/mL of E. coli O157:H7 gave a positive result by using colloidal gold lateral flow after immunomagnetic separation. Food sample spiked with 10 CFU/g of E. coli O157:H7 after 6 h of enrichment could be detected within 72 min of immunomagnetic separation and colloidal gold lateral flow assay. The method is of great value to the rapid on-site detection of harmful substance in food.