title: Contents of selected B vitamins in NIST SRM 3280 multivitamin/multielement tablets by liquid chromatography isotope dilution mass spectrometry.
abstract: There is increased interest in accurately assessing the total dietary intake of vitamins from all sources, including foods and dietary supplements. Consequently, a Dietary Supplement Ingredient Database (DSID), based upon analytical values, is being established by USDA with support of the Office of Dietary Supplements (ODS), NIH. The DSID necessitated the development of a new SRM, 3280--Multivitamin/Multimineral Tablets, by the National Institute of Standards and Technology (NIST), with support from the ODS. As a continuation of a long-term project to develop and validate new methods of determining water-soluble B vitamins in foods and dietary supplements, and as part of a collaborative effort with NIST to characterize SRM 3280, values for the vitamin contents of SRM 3280 have been generated by a liquid chromatographic isotope dilution mass spectrometric (LC/IDMS) method. Isotope-labeled ((13)C and/or (2)H) B vitamins (B1-thiamine, B6-pyridoxine, B3-nicotinamide, and B5-pantothenic acid) were obtained from commercial sources, with the support of the ODS/NIH. Our LC/IDMS method uses a C18 reversed phase column, an Agilent 1100 HPLC system, and a Quattro Micro triple-quad mass spectrometer (MS). B vitamin determination was achieved using a gradient LC profile combined with MS/MS detection in multiple reaction monitoring mode. Stock solutions of the isotope-labeled vitamins were calibrated against USP standard solutions. The SRM tablets, with added amounts of the four isotope-labeled B vitamins, were extracted and the vitamins simultaneously determined in a single LC run, in contrast with the single-component determinations performed via IDMS. Unknown vitamin concentrations were calculated by comparing the ratios of the integrated LC peaks at the different masses of the unlabeled and labeled vitamins.
authors.affiliation: Food Composition Laboratory, USDA-ARS, BHNRC, Beltsville, MD 20705, USA. pei.chen@ars.usda.gov
authors.forename: Pei
authors.initials: P
authors.lastname: Chen
authors.forename: Mustafa
authors.initials: M
authors.lastname: Ozcan
authors.forename: Wayne R
authors.initials: WR
authors.lastname: Wolf
mesh_terms: D002853:Chromatography, Liquid / Q000379:methods*; D019587:Dietary Supplements / Q000032:analysis*; D007201:Indicator Dilution Techniques; D007554:Isotopes / Q000737:chemistry; D013058:Mass Spectrometry / Q000379:methods*; D013607:Tablets / Q000737:chemistry; D037041:United States Government Agencies; D014815:Vitamins / Q000032:analysis* / Q000737:chemistry* / Q000145:classification
chemical_list: D007554:Isotopes; D013607:Tablets; D014815:Vitamins