title: Determination of chemical purity and isotopic composition of natural and carbon-13-labeled arsenobetaine bromide standards by quantitative(1)H-NMR.
abstract: In this study, we report the characterization of three arsenobetaine-certified reference materials by quantitative NMR. We have synthesized an arsenobetaine bromide high-purity standard of natural isotopic composition (ABET-1) and two carbon-13-labeled isotopic standards (BBET-1 and CBET-1). Assignments of the chemical purity and isotopic composition are not trivial in the case of arsenobetaine, and in this study we utilized quantitative(1)H-NMR techniques for the determination of the mass fractions (chemical purity). The isotopic purity of all three standards was also assessed by NMR from the carbon-13 satellite signals. The standards are non-hygroscopic, high-purity (ca. 0.99 g/g), and the carbon-13 enrichment for both isotopic standards is x((13)C)≈0.99. These standards are designed for use as primary calibrators for mass spectrometric determination of arsenobetaine in environmental samples.
authors: Measurement Science and Standards, National Research Council Canada, 1200 Montreal Road, Ottawa, ON K1A 0R6, Canada.
authors: Phuong-Mai
authors: PM
authors: Le
authors: Security and Disruptive Technologies, National Research Council Canada, 1200 Montreal Road, Ottawa, ON K1A 0R6, Canada.
authors: Jianfu
authors: J
authors: Ding
authors: Measurement Science and Standards, National Research Council Canada, 1200 Montreal Road, Ottawa, ON K1A 0R6, Canada.
authors: Donald M
authors: DM
authors: Leek
authors: Measurement Science and Standards, National Research Council Canada, 1200 Montreal Road, Ottawa, ON K1A 0R6, Canada.
authors: Zoltan
authors: Z
authors: Mester
authors: Energy, Mining and Environment, National Research Council Canada, 1200 Montreal Road, Ottawa, ON K1A 0R6, Canada.
authors: Gilles
authors: G
authors: Robertson
authors: Measurement Science and Standards, National Research Council Canada, 1200 Montreal Road, Ottawa, ON K1A 0R6, Canada.
authors: Anthony
authors: A
authors: Windust
authors: Measurement Science and Standards, National Research Council Canada, 1200 Montreal Road, Ottawa, ON K1A 0R6, Canada. juris.meija@nrc-cnrc.gc.ca.
authors: Juris
authors: J
authors: Meija
keywords: Arsenobetaine; Certified reference material; Isotope ratio measurements; NMR; Standard