Solvent extraction method for determination of thorium in soft tissues

Journal Article · Thu Feb 01 04:00:00 EST 1979 · Anal. Chem.; (United States)

DOI:https://doi.org/10.1021/ac50038a013· OSTI ID:6215318

Singh, N P; Ibrahim, S A; Cohen, N; Wrenn, M E

A simple, precise and accurate analytical technique has been developed for the determination of thorium isotopes in soft tissues. The method consists of preliminary nitric acid digestion of tissues after adding /sup 229/Th tracer, followed by a mixture of nitric and sulfuric acid with occasional addition of hydrogen peroxide; thorium is then coprecipitated with iron carrier by ammonium hydroxide. The precipitate is washed until free of sulfate ions, dissolved in 1:1 HNO/sub 3/ and finally adjusted to 4 M HNO/sub 3/. Thorium is extracted twice into 25% trilaurylamine (TLA) in xylene (pre-equilibrated with 4 M HNO/sub 3/) and backwashed twice with 10 M HCl. The aqueous phase is evaporated to almost dryness, treated with H/sub 2/SO/sub 4/ with frequent addition of a few drops of HNO/sub 3/, and electrodeposited onto a platinum planchet prior to ..cap alpha.. spectrometry with a surface-barrier silicon detector. The final total recovery ranged from 24 to 93% with a mean of 65% in 28 samples. Yield appeared to be independent of total iron when 10 to 100 mg Fe were added, and independent of total iron when 10 to 100 mg Fe were added, and independent of the amount of added tracer. The natural /sup 228/Th content of three different beef liver samples was 1.3, 1.4, and 3.0 pCi/kg wet weight. 4 tables.

• Research Organization: New York Univ., NY
• OSTI ID: 6215318
• Journal Information: Anal. Chem.; (United States), Journal Name: Anal. Chem.; (United States) Vol. 51:2; ISSN ANCHA
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400103* -- Radiometric & Radiochemical Procedures-- (-1987)
560100 -- Biomedical Sciences
Applied Studies-- Radiation Effects
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
ABSORPTION SPECTRA
ACCURACY
ACTINIDE ISOTOPES
ACTINIDE NUCLEI
ACTINIDES
ALPHA DECAY RADIOISOTOPES
ALPHA SPECTRA
AMINES
AMMONIUM COMPOUNDS
AMMONIUM HYDROXIDES
AROMATICS
BODY
CHEMICAL ANALYSIS
CHEMICAL REACTION YIELD
CHEMICAL REACTIONS
COMPARATIVE EVALUATIONS
COPRECIPITATION
DEPOSITION
DIGESTION
DIGESTIVE SYSTEM
ELECTRODEPOSITION
ELECTROLYSIS
ELEMENTS
ERRORS
EVEN-EVEN NUCLEI
EXTRACTION
GLANDS
HEAVY NUCLEI
HYDROCARBONS
HYDROGEN COMPOUNDS
HYDROGEN PEROXIDE
HYDROXIDES
INORGANIC ACIDS
IRON
ISOTOPE APPLICATIONS
ISOTOPES
LIVER
LYSIS
METALS
NITRIC ACID
NUCLEI
ORGANIC COMPOUNDS
ORGANS
OXYGEN COMPOUNDS
PEROXIDES
PH VALUE
PRECIPITATION
QUANTITATIVE CHEMICAL ANALYSIS
RADIOISOTOPES
SAMPLE PREPARATION
SEPARATION PROCESSES
SOLVENT EXTRACTION
SPECTRA
SULFURIC ACID
SURFACE COATING
THORIUM
THORIUM 228
THORIUM ISOTOPES
TRACER TECHNIQUES
TRANSITION ELEMENTS
TRILAURYLAMINE
XYLENES
YEARS LIVING RADIOISOTOPES
YIELDS