Determination of iodine in oyster tissue by isotope dilution laser resonance ionization mass spectrometry

Journal Article · Thu Feb 15 04:00:00 EST 1990 · Analytical Chemistry (Washington); (USA)

DOI:https://doi.org/10.1021/ac00203a014· OSTI ID:7100785

Fassett, J D; Murphy, T J ^[1]

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1. National Institute of Standards and Technology, Gaithersburg, MD (USA)

The technique of laser resonance ionization mass spectrometry has been combined with isotope dilution analysis to determine iodine in oyster tissue. The long-lived radioisotope, 129I, was used to spike the samples. Samples were equilibrated with the 129I, wet ashed under controlled conditions, and iodine separated by coprecipitation with silver chloride. The analyte was dried as silver ammonium iodide upon a tantalum filament from which iodine was thermally desorbed in the resonance ionization mass spectrometry instrument. A single-color, two-photon resonant plus one-photon ionization scheme was used to form positive iodine ions. Long-lived iodine signals were achieved from 100 ng of iodine. The precision of 127I/129I measurement has been evaluated by replicate determinations of the spike, the spike calibration samples, and the oyster tissue samples and was 1.0%. Measurement precision among samples was 1.9% for the spike calibration and 1.4% for the oyster tissue. The concentration of iodine determined in SRM 1566a, Oyster Tissue, was 4.44 micrograms/g with an estimate of the overall uncertainty for the analysis of +/- 0.12 microgram/g.

• OSTI ID: 7100785
• Journal Information: Analytical Chemistry (Washington); (USA), Journal Name: Analytical Chemistry (Washington); (USA) Vol. 62:4; ISSN 0003-2700; ISSN ANCHA
• Country of Publication: United States
• Language: English

Related Subjects

550501* -- Metabolism-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
ANIMALS
AQUATIC ORGANISMS
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
ELEMENTS
HALOGENS
INTERMEDIATE MASS NUCLEI
INTERNAL CONVERSION RADIOISOTOPES
INVERTEBRATES
IODINE
IODINE 127
IODINE 129
IODINE ISOTOPES
ISOTOPE APPLICATIONS
ISOTOPE DILUTION
ISOTOPE RATIO
ISOTOPES
LASERS
MASS SPECTROSCOPY
METABOLISM
MOLLUSCS
NONMETALS
NUCLEI
ODD-EVEN NUCLEI
OYSTERS
RADIOISOTOPES
SPECTROSCOPY
STABLE ISOTOPES
TRACER TECHNIQUES
YEARS LIVING RADIOISOTOPES