HR: 1340h
AN: B13A-0885    [Abstracts]
TI: High Precision Isotopic Reference Material Program
AU: * Mann, J L
EM: jmann@nist.gov
AF: National Institute of Standards and Technology Analytical Chemistry Division, 100 Bureau Drive, MS8391, Gaithersburg, MD 20899, United States
AU: Vocke, R D
EM: rvocke@nist.gov
AF: National Institute of Standards and Technology Analytical Chemistry Division, 100 Bureau Drive, MS8391, Gaithersburg, MD 20899, United States
AB: Recent developments in thermal ionization and inductively coupled plasma multicollector mass spectrometers have lead to "high precision" isotope ratio measurements with uncertainties approaching a few parts in 10⁶. These new measurement capabilities have revolutionized the study of isotopic variations in nature by increasing the number of elements showing natural variations by almost a factor of two, and new research areas are actively opening up in climate change, health, ecology, geology and forensic studies. Because the isotopic applications are impacting very diverse fields, there is at present little effective coordination between research laboratories over reference materials and the values to apply to those materials. NIST had originally developed the techniques for producing accurate isotopic characterizations, culminating in the NIST Isotopic SRM series. The values on existing materials however are insufficiently precise and, in some cases, may be isotopically heterogeneous. A new generation of isotopic standards is urgently needed and will directly affect the quality and scope of emergent applications and ensure that the results being derived from these diverse fields are comparable. A series of new isotopic reference materials similar to the NIST 3100 single element solution series is being designed for this purpose and twelve elements have been selected as having the most pressing need. In conjunction with other expert users and National Metrology Institutes, an isotopic characterization of the respective 12 selected ampoules from the NIST single element solution series is currently underway. In this presentation the preliminary results of this screening will be discussed as well as the suitability of these materials in terms of homogeneity and purity, long term stability and availability, and isotopic relevance. Approaches to value assignment will also be discussed.
DE: 1040 Radiogenic isotope geochemistry
DE: 1041 Stable isotope geochemistry (0454, 4870)
DE: 1094 Instruments and techniques
SC: Biogeosciences [B]
MN: 2007 Fall Meeting