The use of isotope dilution mass spectrometry for the certification of standard reference materials

摘要: Abstract Isotope dilution mass spectrometry (IDMS) has been used extensively at the U.S. National Bureau of Standards as an accurate method to determine trace element concentrations in natural materials. Thermal ionization is a single technique capable high accuracy and precision, for “definitive” measurements elements sera with 95% confidence limits less than 0.25%. Spark source complementary multielement, high-sensitivity that up 20 sample, typical accuracies 2%–5%. Together appropriate chemical separations, such anion cation exchange, chelate resins, electrodeposition, extraction, IDMS applied elemental concentration ranging over eight orders magnitude, from decigrams/gram picograms/gram. Many these applications have certification broad spectrum biological environmental Standard Reference Materials, including lead Trace Elements Water (SRM 1643), 15 Coal Fly Ash 1633a), uranium Bovine Liver 1577a), mercury water 1642).