Enzyme-Linked Immunosorbent Assay of Benomyl and Thiabendazole in Some Foods

Abstract

Enzyme-linked immunosorbent assays were developed for benomyl as its decomposition product, methyl 2-benzimidazoIe carbamate, and thiabendazole in foods. Immunogens consisting of human serum albumin coupled to 2-succinamidobenzimidazole or 2-{2'-succinamido- 4'-thiazolyl)benzimidazole were used in rabbits to raise antisera that were specific for the respective fungicides. Lower limits of quantitation of 0.35 ppm for benomyl and 0.03 ppm for thiabendazole were established without cleanup of the ethyl acetate extract. Recoveries of benomyl from 3 crops spiked at 0.5 to 10 ppm averaged 89% (range 73-109%) and of thiabendazole from 5 crops spiked at 0.1 to 2.0 ppm were 93% (range 81-105%).

A monoclonal antibody-based ELISA for thiabendazole in liver

“…A 10-min extraction of liver samples with water sufficed for good recovery of TBZ, and these conditions appear ideal for a rapid screening method. The use of the 5-succinamidothiabendazole hapten (II) led to the production of groupspecific antibodies with more versatility than previously reported antibodies (Newsome and Collins, 1987). On the basis of the binding data for antibodies 430 and 448 (Tables I and II), the potential sensitivity for cambendazole is even greater than for TBZ, but adaptation of the extraction method for this drug (with a zero tolerance in food animal tissues) remains to be done.…”

“…Two haptens were prepared for eliciting TBZ-binding antibodies. 2-(2-succinamido-4-thiazolyl)benzimidazole (2-succinamidothiabendazole, I, Figure 1) was prepared according to the procedure of Newsome and Collins (1987), but the succinylation step was done at 50 °C for 20 h in order to avoid formation of the succinimide derivative, and some acetonitrile and dimethyl sulfoxide were added to the reaction in an attempt to maintain homogeneity. The mixture was brought to pH 5 with HC1 solution and stirred well.…”

“…Standard analytical methods for residues of benzimidazole anthelmintics in meat products utilize liquid chromatography with UV detection, with mass spectrometry as the confirmatory method (Bogan and Marriner, 1980; Barker et al, 1990; Marti et al, 1990; Wilson et al, 1991). An immunoassay for thiabendazole using polyclonal antibodies was reported by Newsome and Collins (1987), who analyzed TBZ residues in produce. A need persists for a fast and simple multiresidue screening test that could be used to test for TBZ residues (the sum of TBZ plus 5-hydroxythiabendazole in meat.…”

Quantitative Determination of Thiabendazole in Fruit Juices and Bulk Juice Concentrates Using a Thiabendazole Monoclonal Antibody

“…The tolerance ranges from 10 to 25 ppm depending upon the fruit or vegetable, which is much higher than is normally found on produce. Previous enzyme immunoassay procedures used for analysis of TBZ in juices and concentrates demonstrated significant cross-reactivity with carbendazim, the breakdown product of other widely used fungicides, namely benomyl and thiophanate methyl (Newsome and Collins, 1987;Mountford et al, 1994; Bushway et al, 1994). In addition, carbendazim itself is used as a fungicide outside the United States.…”

Analysis of thiabendazole in potatoes and apples by ELISA using monoclonal antibodies

“…Rapid screening tests could permit testing of more samples and produce greater confidence in the safety of the food supply. An immunoassay method for thiabendazole using organic solvent extraction and polyclonal antibodies was reported by Newsome and Collins (1987). Our approach has been to develop monoclonal antibodies specific for thiabendazole and sample workup procedures that eliminate the need for organic solvents and sophisticated laboratory equipment.…”