The certification of reference materials of dry-mixed maize powder with different mass fractions of 59122 maize : certified reference materials ERM-BF424 : ERM-BF424a, ERM-BF424b, ERM-BF424c, ERM-BF424d

This report describes the preparation and certification of maize powder CRMs with different mass fractions of genetically modified (GM) 59122 maize powder (Certified Reference Materials ERM-BF424a, ERM-BF424b, ERM-BF424c and ERM-BF424d). The materials were processed and certified in 2006 by the European Commission, Directorate General Joint Research Centre, the Institute for Reference Materials and Measurements (IRMM) in Geel, Belgium. Seeds of non-modified maize and 59122 maize both supplied by Pioneer Hi-Bred International (Johnston, IA, USA) were rinsed with demineralised water, drained and dried at 30 °C in order to minimise dust contamination from other crops. After a two step grinding process, transforming the seeds into a non-modified maize powder and a 59122 GM maize powder, the mixtures, containing different mass fractions of GM, were gravimetrically prepared by dry-mixing. The CRMs are intended for the quality control and calibration of methods for the detection of genetically modified food. The 59122 mass fractions of ERM-BF424 were verified with the help of DNA-based detection methods. The CRMs are available in glass bottles containing 1 g of maize powder packed under argon atmosphere.