The Development Of The Matrix Reference Materials For Detection Of Genetically Modified Rice TT51-1

In2009, the genetically modified (GM) rice TT51-1got the certificatefor producing by Ministry of Agriculture of China. The research anddevelopment of reference materials of GM rice TT51-1is very important forthe implemention of the genetically modified organism (GMO) labelingregulation in China. In this study, we focused on developing and evaluatingsystem for GM rice matrix reference material.The technical system of the homogeneity assessment, stabilityassessment, assignment of certified value and uncertainty evaluation for GMrice matrix reference materials was established employing the Real-time PCRmethod. Meanwhile, the methods were applied to evaluate the three kinds ofdeveloped TT51-1matrix reference materials.1）Homogeneity study. Within-bottle homogeneity and between-bottlehomogeneity were analyzed and F-test analysis proved the satisfactoryhomogeneity.2）Stability study. Two types of stability testing were performed, the short-term stability testing at elevated temperatures (-20°C，4°C, roomtemperature,37°C,60°C) within8weeks and the long-term stability testingat storage temperatures (-20°C，4°C, room temperature) periodically up to oneyear. T-test analysis showed that the samples were unstable at60°C for8weeks. TT51-1matrix reference materials can be transported at-20°C，4°C,room temperature or37°C within8weeks at least except at extremelytemperature60°C for four weeks. The statistical analysis results of long-termstability proved that TT51-1matrix reference materials can be stored stably at-20°C,4°C and room temperature for at least one year.3）Assignment of certified value and uncertainty evaluation. Based onthe high homogeneity and stability, we invited eight laboratories which wereaccredited in agreement with ISO guide34(2009) to participate in theinter-laboratory collaborative study. The statistical analysis of the valid datafrom seven laboratories showed the true copy number ratio of matrixreference materials were as follows:0.56%±0.10%,1.18%±0.24%,5.10%±0.58%.This study contributed to the establishment of quality assessment systemof four key parameters in the development of GM rice matrix referencematerials and laid the foundation for applicatioin of the reference materialcertificate of TT51-1. This is of positive significance to the development of GM rice reference materials.