Affiliation: | (1) Center for Analytical Chemistry, Institute for Agrobiotechnology (IFA-Tulln), Konrad Lorenz Strasse 20, 3430 Tulln, Austria;(2) DG Joint Research Centre, Institute for Reference Materials and Measurements, European Commission, Retieseweg, 2440 Geel, Belgium;(3) Central Science Laboratory, Sand Hutton, York, YO41 1LZ, UK;(4) Department of Animal Nutrition and Management, Swedish University of Agricultural Sciences, P.O. Box 7024, 750 07 Uppsala, Sweden |
Abstract: | Several previous interlaboratory studies in the field of mycotoxin analysis have revealed considerable problems, apparent as high between-laboratory standard deviations, or rather non-comparable and non-traceable results. A major reason is lack of proper calibrants for external calibration. Public awareness of substances that mimic or interfere with the activity of natural hormones (endocrine disrupters) has led to increased interest in mycotoxins with estrogenic potential, e.g. zearalenone (ZON). During a large-scale standard measurement and testing (SMT) project of the European Commission (EC) dealing with the preparation and certification of reference materials for determination of the mycotoxin ZON in maize, a ZON calibrant in acetonitrile was prepared and intensively checked for purity, homogeneity, and stability. Preparation of the material, study of its homogeneity and stability, and characterisation of the calibrant on the basis of its preparation, with discussion of the results obtained, are described in this paper. The certified value of 9.95 µg mL–1 for ZON in acetonitrile and its corresponding expanded uncertainty of ±0.30 µg mL–1 were calculated in compliance with the Guide to the Expression of Uncertainty in Measurement (GUM). |