title: In-house validation of an ELISA method for screening of semicarbazide in eggs.
abstract: An enzyme-linked immunosorbent assay (ELISA) method is described for the semi-quantitative determination of semicarbazide (SEM), the marker residue for the banned nitrofuran drug, nitrofurazone, in chicken eggs. The sample homogenate is subjected to acid hydrolysis and derivatisation with o-nitrobenzaldehyde, followed by ethyl acetate/hexane extraction and detection by ELISA. The ELISA procedure has been validated using 0.3, 1.0 and 3 microg kg(-1) of SEM in fortified samples. Detection capability (CC(ss)) was based on the acceptance of 5% false compliant results for a given concentration level according to Commission Decision 2002/657/EC and was determined to be 0.3 microg kg(-1) with a respective limit of detection of 0.13 microg kg(-1). A validated LC-MS/MS method was used for the analysis of incurred egg samples and the results compared with ELISA. A good correlation between the results obtained from ELISA and LC-MS/MS within the concentration range 0.12-20.3 microg kg(-1) was observed in samples collected from chickens fed with a medicated ration of nitrofurazone (r = 0.992, n = 14). Validated ELISA enabled reliable monitoring of SEM levels in eggs collected from incurred chickens over a 90-day period.
authors.affiliation: Veterinary Research Institute, Brno 62100, Czech Republic.
authors.forename: Maria
authors.initials: M
authors.lastname: Vass
authors.forename: Iva
authors.initials: I
authors.lastname: Diblikova
authors.forename: Eloise
authors.initials: E
authors.lastname: Kok
authors.forename: Kamil
authors.initials: K
authors.lastname: Stastny
authors.forename: Karla
authors.initials: K
authors.lastname: Frgalova
authors.forename: Karel
authors.initials: K
authors.lastname: Hruska
authors.forename: Milan
authors.initials: M
authors.lastname: Franek
mesh_terms: D000818:Animals; D002273:Carcinogens / Q000032:analysis*; D002645:Chickens; D002853:Chromatography, Liquid / Q000379:methods; D004350:Drug Residues / Q000032:analysis; D004335:Drug and Narcotic Control; D004531:Eggs / Q000032:analysis*; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods*; D005260:Female; D005506:Food Contamination / Q000032:analysis*; D013058:Mass Spectrometry / Q000379:methods; D009583:Nitrofurazone; D012663:Semicarbazides / Q000032:analysis*
chemical_list: D002273:Carcinogens; D012663:Semicarbazides; C010059:carbamylhydrazine; D009583:Nitrofurazone