Article

Development and Certification of a Standard Reference Material for Vitamin D Metabolites in Human Serum

Analytical Chemistry Division, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, United States.
Analytical Chemistry (Impact Factor: 5.83). 12/2011; 84(2):956-62. DOI: 10.1021/ac202047n
Source: PubMed

ABSTRACT The National Institute of Standards and Technology (NIST), in collaboration with the National Institutes of Health's Office of Dietary Supplements (NIH-ODS), has developed a Standard Reference Material (SRM) for the determination of 25-hydroxyvitamin D [25(OH)D] in serum. SRM 972 Vitamin D in Human Serum consists of four serum pools with different levels of vitamin D metabolites and has certified and reference values for 25(OH)D(2), 25(OH)D(3), and 3-epi-25(OH)D(3). Value assignment of this SRM was accomplished using a combination of three isotope-dilution mass spectrometry approaches, with measurements performed at NIST and at the Centers for Disease Control and Prevention (CDC). Chromatographic resolution of the 3-epimer of 25(OH)D(3) proved to be essential for accurate determination of the metabolites.

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