title: Chemotyping the distribution of vitamin D metabolites in human serum.
abstract: Most studies examining the relationships between vitamin D and disease or health focus on the main 25-hydroxyvitamin D3 (25(OH)D3) metabolite, thus potentially overlooking contributions and dynamic effects of other vitamin D metabolites, the crucial roles of several of which have been previously demonstrated. The ideal assay would determine all relevant high and low-abundant vitamin D species simultaneously. We describe a sensitive quantitative assay for determining the chemotypes of vitamin D metabolites from serum after derivatisation and ultra-high performance liquid chromatography-electrospray ionisation-tandem mass spectrometry (UHPLC-ESI-MS/MS). We performed a validation according to the 'FDA Guidance for Industry Bioanalytical Method Validation'. The proof-of-concept of the method was then demonstrated by following the metabolite concentrations in patients with chronic liver diseases (CLD) during the course of a vitamin D supplementation study. The new quantitative profiling assay provided highly sensitive, precise and accurate chemotypes of the vitamin D metabolic process rather than the usually determined 25(OH)D3 concentrations.
authors: Institute of Bioanalytical Chemistry, Saarland University, Saarbrücken, Germany.
authors: Miriam J
authors: MJ
authors: Müller
authors: Department of Medicine II, Saarland University Medical Center, Homburg, Germany.
authors: Caroline S
authors: CS
authors: Stokes
authors: Department of Medicine II, Saarland University Medical Center, Homburg, Germany.
authors: Frank
authors: F
authors: Lammert
authors: Institute of Bioanalytical Chemistry, Saarland University, Saarbrücken, Germany.
authors: Dietrich A
authors: DA
authors: Volmer
mesh_terms: D015650:24,25-Dihydroxyvitamin D 3 / Q000097:blood*; D002112:Calcifediol / Q000097:blood*; D002117:Calcitriol / Q000008:administration & dosage / Q000097:blood*; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D019587:Dietary Supplements; D006801:Humans; D008099:Liver / Q000378:metabolism / Q000473:pathology; D008103:Liver Cirrhosis / Q000097:blood* / Q000178:diet therapy / Q000473:pathology; D012680:Sensitivity and Specificity; D021241:Spectrometry, Mass, Electrospray Ionization; D053719:Tandem Mass Spectrometry; D014808:Vitamin D Deficiency / Q000097:blood* / Q000178:diet therapy / Q000473:pathology
chemical_list: D015650:24,25-Dihydroxyvitamin D 3; D002117:Calcitriol; D002112:Calcifediol