Rapid and sensitive determination of radiocesium (Cs-135, Cs-137) in the presence of excess barium by electrothermal vaporization-inductively coupled plasma-mass spectrometry (ETV-ICP-MS) with potassium thiocyanate as modifier.

Autor: Song, Ming, Probst, Th. U., Berryman, Natalia G.
Zdroj: Fresenius' Journal of Analytical Chemistry; Jul2001, Vol. 370 Issue 6, p744-751, 8p
Abstrakt: An electrothermal vaporization-inductively coupled plasma-mass spectrometric (ETV-ICP-MS) method based on selective volatilization of cesium with KSCN as modifier has been developed for determination of radiocesium, i.e. 135Cs and 137Cs, in the presence of isobaric barium. A 10000 times excess of barium, which was volatilized at a temperature of 1100 °C, resulted only in a 1% signal increase in the signal of mass 135 amu. The recommended concentration of KSCN is 0.3 mM, and pretreatment and volatilization temperatures are 400 °C and 1100 °C, respectively. A ramp time of 1 s is recommeded for the volatilization step. The achieved limit of detection for 135Cs is 0.2 pg/mL (10 μBq/mL) and 4 fg (0.2 μBq) absolute for a sample volume of 20 μL. This means a limit of detection for 137Cs of 0.2 pg/mL (0.6 Bq/mL) and of 4 fg (0.01 Bq) absolute. Signal variations of 135Cs and 137Cs, respectively, in spiked samples with various matrices were investigated. [ABSTRACT FROM AUTHOR]
Databáze: Complementary Index
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