title: Improved isolation of Escherichia coli O157 using large enrichment volumes for immunomagnetic separation.
abstract: The recovery of low numbers of Escherichia coli O157 in foods by immunomagnetic separation (IMS) was improved, on average, ninefold by increasing the enrichment volume tested from 1 to 10 ml while maintaining the volume of immunobeads constant at 0.02 ml. Although 50 ml volumes also gave improved recoveries (approximately threefold), the 50 ml volume cannot be recommended until a suitable magnetic separation apparatus has been developed. By testing 10 ml volumes, the improved sensitivity of the IMS procedure will reduce false-negative E. coli O157 tests and help improve epidemiological studies of this pathogen.
authors.affiliation: Department of Medical Microbiology, University of Aberdeen, Foresterhill, UK. i.ogden@abdn.ac.uk
authors.forename: I D
authors.initials: ID
authors.lastname: Ogden
authors.forename: M
authors.initials: M
authors.lastname: MacRae
authors.forename: N F
authors.initials: NF
authors.lastname: Hepburn
authors.forename: N J
authors.initials: NJ
authors.lastname: Strachan
mesh_terms: D000818:Animals; D001431:Bacteriological Techniques; D002417:Cattle; D003470:Culture Media; D019453:Escherichia coli O157 / Q000254:growth & development / Q000302:isolation & purification*; D018189:Immunomagnetic Separation / Q000379:methods*; D008461:Meat Products / Q000382:microbiology*; D012680:Sensitivity and Specificity
chemical_list: D003470:Culture Media