Development, validation and data quality assurance of screening methods: a case study.

Despite the growing importance of qualitative screening tests in routine laboratories involved in the EU official control, their validation is not as deeply explained in Commission Decision 2002/657/EC as the validation of quantitative confirmatory methods. At the same time, the issue of quality assurance of screening assays defining internal quality control (IQC) procedures as required by accreditation bodies is undoubtedly less developed in this analytical field. As an example the present study describes the development, the validation and the IQC implemented for a commercial enzyme linked immunosorbent assay (ELISA) able to detect 17-α-19-nortestosterone (α-NT) and 17-β-19-nortestosterone (β-NT) isomers in bullock urine.

Validation of an enzyme-linked immunosorbent assay screening for quinolones in egg, poultry muscle and feed samples.

Quinolones are a group of chemotherapeutic agents with an excellent efficiency against poultry pathogens. Two commercial enzyme-linked immunosorbent assay (ELISA) tests have been applied in parallel for the qualitative screening analysis of several quinolones in eggs, poultry muscle and feeds at the required levels. During the validation study, carried out according to the Commission Decision 2002/657/EC criteria, two different sample treatments were compared in foods: the simple and fast procedure suggested by the kit producer (Euro-Diagnostica) and a more complex solid-phase extraction (SPE) sample preparation.