Development of an ELISA screening test for nitroimidazoles in egg and chicken muscle

An antibody was generated that can bind metronidazole (MNZ), a nitroimidazole drug used in veterinary medicine to treat poultry for coccidiosis and histomoniasis. A direct competitive enzyme-linked immunosorbent assay (cELISA) is described. It was used to characterise binding of this antibody to a number of nitroimidazole drugs. It displayed cross-reactivity with dimetridazole (DMZ), ronidazole (RNZ), hydroxydimetridazole (DMZOH), and ipronidazole (IPZ). Egg and chicken muscle samples were extracted with acetonitrile and de-fatted by washing with hexane. Detection capabilities (CC beta) were determined: dimetridazole. < 1 ppb (egg) and < 2 ppb (muscle); metronidazole, < 10 ppb; ronidazole and hydroxydimetridazole, < 20 ppb; ipromdazole, < 40 ppb. (c) 2004 Elsevier B.V. All rights reserved.