%A SHAN Lu-Ying, LI Jun, LI Liang, ZHANG Li, WANG Hao-Qian, GAO Jia-Qi, WU Gang, WU Yu-Hua, ZHANG Xiu-Jie %T Development of genetically modified maize (Zea mays L.) NK603 matrix reference materials %0 Journal Article %D 2022 %J Acta Agronomica Sinica %R 10.3724/SP.J.1006.2022.13025 %P 1059-1070 %V 48 %N 5 %U {https://zwxb.chinacrops.org/CN/abstract/article_7331.shtml} %8 2022-05-12 %X

The implementation of genetically modified organisms (GMO) safety management and labeling system requires standardized testing methods and reference materials (RMs). Furthermore, the RMs are the guarantee of obtaining accurate, reliable and comparable testing results. At present, genetically modified (GM) maize (Zea mays L.) NK603 has been approved to be imported as processing raw material in China, and its safety supervision urgently needs to prepare RMs. In this study, the heterozygous seeds of GM maize NK603 and the non-GM maize counterpart after identification were well milled and then gravimetrically mixed to prepare three levels of powder RMs according to the mass fractions of 60.0, 100.0, and 1000 mg g-1. The homogeneity and stability test by duplex ddPCR method showed that the RMs of GM maize NK603 were homogenous and stable for not less than six months. The property values were collaboratively characterized by eight laboratories using duplex ddPCR method. The certified values together with their expanded uncertainties were (2.75±0.26)%, (4.68±0.39)%, and (51.8±3.7)%, respectively. The minimum sample intake was determined to be 100 mg. This batch of RMs can be used for the qualitative and quantitative detection of NK603 event in food and feed, as well as for the evaluation of GM maize NK603-specific assays and laboratory quality control.