title: Determination of citrinin in barley by indirect and direct enzyme immunoassay.
abstract: Polyclonal antibodies against the mycotoxin citrinin were raised in rabbits after immunization with citrinin conjugated to keyhole limpet hemocyanin. The antibodies were used in a competitive indirect enzyme immunoassay (EIA) with citrinin coupled to glucose oxidase as the solid-phase antigen for coating microtiter plates. Detection limits of this indirect EIA for citrinin ranged from 0.4 to 0.8 ng/mL for buffer solutions. Recoveries of citrinin added to ground barley at 100-2000 ng/g ranged from 105 to 112%, with coefficients of variation between 4.5 and 12%. A direct competitive EIA also was established, with citrinin coupled to horseradish peroxidase as the labeled antigen. Detection limits of this direct EIA for citrinin ranged from 2 to 4 ng/mL for buffer solutions. Recoveries of citrinin added to ground barley at 500-2000 ng/g ranged from 108 to 111%, with coefficients of variation between 8.4 and 26.9%. In naturally contaminated barley samples assayed with the indirect EIA, optimum extraction of citrinin was obtained in 30 min, and only one extraction was necessary to recover 72-76% of the analyte.
authors.affiliation: Agriculture and Agri-Food Canada, Cereal Research Center, Winnipeg, Canada.
authors.forename: D
authors.initials: D
authors.lastname: Abramson
mesh_terms: D000276:Adjuvants, Immunologic / Q000378:metabolism; D000818:Animals; D000900:Anti-Bacterial Agents / Q000032:analysis*; D002953:Citrinin / Q000032:analysis* / Q000097:blood; D019085:Fluorescent Antibody Technique, Direct; D005504:Food Analysis; D005506:Food Contamination; D005557:Formaldehyde / Q000737:chemistry; D005620:Freund's Adjuvant / Q000378:metabolism; D006433:Hemocyanins / Q000378:metabolism; D001467:Hordeum / Q000737:chemistry*; D007124:Immunoenzyme Techniques; D011817:Rabbits
chemical_list: D000276:Adjuvants, Immunologic; D000900:Anti-Bacterial Agents; D005557:Formaldehyde; D002953:Citrinin; D005620:Freund's Adjuvant; D006433:Hemocyanins; C032808:keyhole-limpet hemocyanin