Digital PCR-Based characterization of a Zhonghuang 6106 soybean genomic DNA reference material for its food and feed detection

The genomic DNA reference material of genetically modified soybean Zhonghuang6106, developed in this study, was prepared by extracting genomic DNA from the leaves of both homozygous transgenic soybean Zhonghuang 6106 and non-transgenic soybean Zhonghuang10, followed by proportional mixing of the genomic DNA. Eight qualified laboratories independently validated the certified reference material (CRM) using the digital polymerase chain reaction (dPCR) method. The certified value for the transgene-specific sequence copy number concentration was determined to be (1.04 ± 0.16)×10³ copies·µL^-1, while the copy number ratio of Zhonghuang 6106 to Lectin was 0.047 ± 0.006.Homogeneity and stability assessments revealed that this batch of CRMs exhibited excellent homogeneity and could be stably stored for up to 10 days at 37 °C. Additionally, it remained stable for up to 6 months at -20 °C. This reference material can be used for qualitative and quantitative detection of genetically modified soybean Zhonghuang 6106 and its related products, as well as for the evaluation of specific detection methods and laboratory quality control.