GA/T 1633-2019 in English

Analysis of Standard Technical Framework

Key technical points

The standard adopts a triple quadrupole mass spectrometer, and significantly improves the detection specificity through the multiple reaction monitoring (MRM) mode:

• GC-MS/MS: 261>143 is used as the quantitative ion pair, and the detection limit is reduced by 10 times after derivatization
• LC-MS/MS: 221>75 ion pairs are used to avoid interference from the urine matrix

Recommendations for the implementation of the standard

1. Laboratories should regularly verify the separation efficiency of the HP-1MS column and the Inertsil ODS-3 column
2. It is recommended to use the isotopic internal standard EtG-D5 to control the extraction recovery rate at 85-115%
3. For corrupt samples, false positives should be excluded in combination with LC-MS/MS results

Analysis of technological evolution

Compared with the traditional GC-MS method, this standard:

• Extends the detection window from 8 hours to 12 hours
• Adds LC-MS/MS method to solve the derivatization loss problem of highly polar compounds
• Introduces the quality control indicator of relative phase difference (RD≤20%)