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Determination of 24,25-dihydroxyvitamin D3 in Vitamin D External Quality Assessment Scheme samples using a reference measurement procedure
Published
Author(s)
Stephen Wise, Grace Hahm, Carolyn Burdette, Susan Tai, Johanna Camara, Adam Kuszak, Emma Williams
Abstract
Ninety archived human serum samples from the Vitamin D External Quality Assessment Scheme (DEQAS) were analyzed using a reference measurement procedure (RMP) based on isotope dilution liquid chromatography - tandem mass spectrometry (ID LC-MS/MS) for the determination of 24,25-dihydroxyvitamin D3 [24,25(OH)2D3]. These 24,25(OH)2D3 results, in conjunction with concentration values assigned using RMPs for 25-hydroxyvitamin D2 [25(OH)D2] and 25-hydroxyvitamin D3 [25(OH)D3], provide a valuable resource for assessing the accuracy of measurements for 24,25(OH)2D3 and for investigating the relationship between 24,25(OH)2D3 and 25(OH)D3. Results for 24,25(OH)2D3 using the RMP were compared to DEQAS consensus values demonstrating that the consensus values were not sufficient to assess the accuracy of measurements among different laboratories and methods. A multivariable regression analysis approach using historical DEQAS consensus values for various total 25(OH)D assays was used to assess the contribution of 24,25(OH)2D3 concentration on the assay response. The response of several ligand binding assays for total 25(OH)D was shown to be impacted by the presence of 24,25(OH)2D3.
Citation
Journal of Steroid Biochemistry and Molecular Biology
24, 25-dihydroxyvitamin D(3), Immunoassay, Liquid chromatography – tandem mass spectrometry (LC-MS/MS), Reference measurement procedure (RMP), Standard Reference Material (SRM), Total 25-Hydroxyvitamin D, Vitamin D Standardization Program (VDSP)
Wise, S.
, Hahm, G.
, Burdette, C.
, Tai, S.
, Camara, J.
, Kuszak, A.
and Williams, E.
(2023),
Determination of 24,25-dihydroxyvitamin D3 in Vitamin D External Quality Assessment Scheme samples using a reference measurement procedure, Journal of Steroid Biochemistry and Molecular Biology, [online], https://doi.org/10.1016/j.jsbmb.2023.106318, https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=935668
(Accessed October 13, 2025)