Atomic absorption spectrometric determination of selenium with carbon furnace atomization

Direct experimental evidence for in situ graphite and palladium selenide formations with improvement on the sensitivity of selenium in graphite furnace atomic absorption spectrometry

“…Dimethyl selenide and diethyl selenide have very low melting points of 58 °C and 135 °C, respectively. Also formation of smoke and carbon particles causes blocking of the light path through the graphite tube (10). However if some or all of the above could be avoided, the usefulness of the graphite furnace in the determination of Se will be improved.…”

“…Several reports (1,5, 7,10) favoring the addition of nickel claim the formation of a high boiling selenide. Ihnat (10) remarked that reduction by nickel oxide of Se02, formed by decomposition of selenite or selenate, to a less volatile form is another possibility. As an example of a different modifier Henn (11) utilized molybdenum and put forward that the formation of a high molecular weight heteropoly molybdate anion is successful at isolating the selenium.…”

Interlaboratory trial on the determination of total selenium in lyophilized human blood serum

“…Inorganic constituents of the matrix remaining after acid decomposition of foodstuffs were observed (Refs. 18,19) to almost totally obliterate the Se signal from the graphite furnace used. Although recent designs of graphite furnace and general improvements in technique make possible the direct determination of Se in biological fluids, some analysts feel that separation of the analyte from interfering components of the matrix is advantageous.…”

Determination of selenium in the environment and in biological material.

“…Pierce et al (136) Ihnat and Westerby (27) used FAAS for estimation of selenium in tissues and powdered milk after mineralization in a HN03-HC104 mixture, precipitation of selenium with ascorbic acid and dissolution in a mixture of 0.6N HN03 and 4.2N HC104. Then Ihnat reported (24) application of a similar procedure for determination of selenium in the range of and below 1 jig/g in various other materials, including flour and animal tissues with addition of nickel salts (5 mg/ml) into analyzed solutions in order to improve precision of the assay. The detection limit so obtained was 25 ng/g.…”