Determination of selenium in blood by pseudo-cyclic instrumental neutron activation analysis

Conference · Tue Jan 01 04:00:00 EST 1991 · Transactions of the American Nuclear Society; (United States)

OSTI ID:5596374

Chatt, A; Holzbecher, J ^[1]

---

1. Dalhousie Univ., Halifax, Nova Scotia (Canada)

There is increasing interest in understanding the role of selenium in human and animal metabolism. Analytical methods are being developed in several laboratories for the determination of total selenium in whole blood, serum, urine, soft and hard tissues, food, water, etc. The levels of selenium in human blood are generally too low for direct determination by most analytical techniques except neutron activation analysis (NAA). Selenium has six stable isotopes that produce seven nuclides on thermal neutron activation. Among these nuclides, {sup 77m}Se and {sup 75}Se are most suitable for measurement by instrumental NAA (INAA). The 264.6-keV gamma ray of {sup 75}Se is free from interference and is commonly employed. The use of this long-lived nuclide generally requires lengthy irradiations at a high neutron flux, decay, and counting periods that could take up to 2 to 3 weeks of experimental time. Obviously, it is a time-consuming and expensive procedure and may not be suitable for routine analysis of a large number of samples for selenium in blood. Alternatively, the short-lived {sup 77m}Se nuclide can be used in routine INAA to considerably reduce the total experimental time and cost. Although the conventional INAA procedure involving a one-shot irradiation-decay-counting scheme can be used, precision and detection limit can be significantly improved by using cyclic INAA (CINAA). In CINAA, a sample is irradiated for a short time and is rapidly transferred to a detector for counting for a short period. The entire process is immediately repeated for an optimum number of cycles. If several days are allowed to elapse between repetitions of the irradiation-decay-counting cycles, then the technique is called pseudo-cyclic INAA (PCINAA). A PCINAA method has been developed in this laboratory for the determination of selenium in human whole blood and serum samples.

• OSTI ID: 5596374
• Report Number(s): CONF-910603--
• Conference Information: Journal Name: Transactions of the American Nuclear Society; (United States) Journal Volume: 63
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400101 -- Activation
Nuclear Reaction
Radiometric & Radiochemical Procedures
560300* -- Chemicals Metabolism & Toxicology
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
ACTIVATION ANALYSIS
ANIMALS
BETA DECAY RADIOISOTOPES
BIOLOGICAL MATERIALS
BLOOD
BODY FLUIDS
CHEMICAL ANALYSIS
DAYS LIVING RADIOISOTOPES
ELECTRON CAPTURE RADIOISOTOPES
ELEMENTS
EVEN-ODD NUCLEI
INTERMEDIATE MASS NUCLEI
ISOMERIC NUCLEI
ISOMERIC TRANSITION ISOTOPES
ISOTOPES
MAMMALS
MAN
MATERIALS
METABOLISM
NEUTRON ACTIVATION ANALYSIS
NUCLEI
PRIMATES
RADIOISOTOPES
SECONDS LIVING RADIOISOTOPES
SELENIUM
SELENIUM 75
SELENIUM 77
SELENIUM ISOTOPES
SEMIMETALS
STABLE ISOTOPES
VERTEBRATES