Certification of reference materials of potato powder with different mass fractions of the event AM04-1020 : certified reference materials ERM®-BF430 (ERM®-BF430a, ERM®-BF430b, ERM®-BF430c, ERM®-BF430d, ERM®-BF430e)

This report describes the processing and certification of five potato powder Certified Reference Materials (CRMs) containing different mass fractions of genetically modified (GM) AM04-1020 potato (ERM-BF430a, b, c, d, e). The materials were prepared and certified in 2010 and 2011 by the European Commission, Joint Research Centre, Institute for Reference Materials and Measurements (IRMM, Geel, Belgium), according to the principles of ISO Guide 34. The five CRMs have been accepted as European Reference Material (ERM®) after peer evaluation by the partners of the European Reference Materials consortium. GM tubers of AM04-1020 potato and of a non-GM potato variety were washed and dried. Afterwards they were ground with a cryo-grinding vibrating mill to obtain a GM and non-GM powder base material. Gravimetric mixtures of non-GM and GM potato powder were made by dry-mixing. A first material was made by mixing non-GM and GM potato powder and two additional ones by further dilution of the mixture with non-GM potato powder. The certified values of these CRMs were calculated from the gravimetric preparations, taking into account the respective purity of the base materials and their water mass fractions. Quantification of the mass fraction of AM04-1020 in the powders by quantitative real-time polymerase chain reaction confirmed the dilution process of the gravimetrically prepared ERM-BF430 (measurements within the scope of accreditation to ISO/IEC 17025).