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Development of Standard Reference Material (SRM) 2973 Vitamin D Metabolites in Frozen Human Serum (High Level)



Susan Tai, Michael Nelson, Brian Lang, Karen W. Phinney, Lane C. Sander, James H. Yen, J. M. Betz, Christopher T. Sempos, Stephen Wise


The National Institute of Standards and Technology (NIST), in collaboration with the National Institutes of Health, Office of Dietary Supplements (NIH-ODS) and the Vitamin D Standardization Program (VDSP), has recently issued a new serum-matrix Standard Reference Material (SRM), SRM 2973 Vitamin D Metabolites in Frozen Human Serum (High Level). SRM 2973 was designed to provide a serum material with a total 25-hydroxyvitamin D [25(OH)D] concentration near 100 nmol/L to complement the existing serum-based SRMs with values assigned for total 25(OH)D between 20 nmol/L to 80 nmol/L. Values were assigned for 25-hydroxyvitamin D2 [25(OH)D2], 25-hydroxyvitamin D3 [25(OH)D3], 3-epi-25(OH)D3, and total 25(OH)D3 [sum of 25(OH)D2 + 25(OH)D3] using the NIST liquid chromatography - tandem mass spectrometry (LC-MS/MS) reference measurement procedure (RMP) and related methods. SRM 2973 has a certified value of 98.4 ± 2.1 nmol/L for 25(OH)D3 and reference values of 1.59 ± 0.05 nmol/L for 25(OH)D2 and 5.23 ± 0.20 nmol/L for 3-epi-25(OH)D3. In addition, a candidate RMP for 24R,25-dihydroxyvitamin D3 [24R,25(OH)2D3] based on LC-MS/MS was used to assign values to SRM 2973 and the existing SRM 972a Vitamin D Metabolites in Frozen Human Serum. Reference values for 24R,25(OH)2D3 were assigned to SRM 2973 (7.51 nmol/L ± 0.26 nmol/L) and SRM 972a Level 1 (6.38 nmol/L ± 0.23 nmol/L), Level 2 (3.39 nmol/L ± 0.12 nmol/L), Level 3 (3.88 nmol/L ± 0.013 nmol/L), and Level 4 (6.32 nmol/L ± 0.22 nmol/L). These two SRMs are the first serum-based certified reference materials with values assigned for concentrations of 24R,25(OH)2D3.
Journal of Aoac International


Standard Reference Material (SRM), liquid chromatography – tandem mass spectrometry (LC-MS/MS), 24R, 25-dihydroxyvitamin D3, 25-hydroxyvitamin D3, 25-hydroxyvitamin D2, reference measurement procedure (RMP)


Tai, S. , Nelson, M. , Lang, B. , Phinney, K. , Sander, L. , Yen, J. , Betz, J. , Sempos, C. and Wise, S. (2017), Development of Standard Reference Material (SRM) 2973 Vitamin D Metabolites in Frozen Human Serum (High Level), Journal of Aoac International (Accessed February 22, 2024)
Created July 23, 2017, Updated October 12, 2021