Establishment and application of an isotope dilution chromatography tandem mass spectrometry reference method for Hcy quantification / 中华检验医学杂志

ABSTRACT

Objective To establish a reference measurement procedure for the determination of human serum homocysteine by isotope dilution high performance liquid chromatography-tandem mass spectrometry (ID-LC/MS/MS), and to apply it to establish sample target values for external quality assessment (EQA) in clinical laboratories. Methods The reference method of Hcyquantification in our laboratory was establishedaccording to the method recommended by the Joint Committee for Traceability in Laboratory Medicine (JCTLM). The precision, trueness, specificity, residue and matrix effect of the method were evaluated. The reference method was applied to establish Hcy target values for samples of the second EQA in Shanghai of 2018. Results The method detects 12.5μmol/L and 37.4μmol/L samples in three batches in three days, and the CV between batches is 1.03％and 2.10％, respectively. The measured values of Standard reference material (SRM) 1955 of National Institute of Standards and Technology (NIST) were within the specified uncertainty range. No matrix effect and carryover were observed. The second EQA data in 2018 showed that the average value of domestic reagent group was lower than that of reference method, and that of imported reagent group was higher than that of reference method. Conclusion Thereference measurement procedure of ID-LC/MS/MS was successfully established to determine the human serum homocysteine. It is expected to play a role in tracing the quantities of Hcy in clinical laboratories.