A novel approach to cold vapor generation for the determination of mercury in biological samples

Journal of the Brazilian Chemical Society

Instituto de Tecnologia do Paraná, Curitiba, Brazil¹  Curtius, Adilson José¹  Sturgeon, Ralph Edward¹  National Research Council Canada, Ottawa, Canada¹  Herrmann, Amanda Beatriz¹  Universidade Federal de Santa Catarina, Florianópolis, Brazil¹  Frescura, Vera Lúcia Azzolin¹  Santos, Eder José dos¹ 

关键词: mercury;    alkaline pH;    inductively coupled plasma optical emission spectrometry;    cold vapor generation;    biological samples;   

DOI  :  10.1590/S0103-50532008000500018

学科分类：化学（综合）

来源: SciELO

【 摘 要 】

A novel approach to the generation of mercury vapor at high pH by the simple addition of NaOH or other base to a solution containing mercury ions is described. Subsequent addition of another reducing agent, such as NaBH4 or SnCl2, is unnecessary. Following total dissolution of sample using HNO3 and H2O2 in a closed microwave vessel, the pH of the sample solution is increased to 13 by the addition of NaOH. After standing for 90 min in a closed vessel, the Hg0 is directed to the plasma by a flow of argon. Emission from mercury is measured at 253.652 nm by an axial view inductively coupled plasma optical emission spectrometer (ICP OES). The procedure was applied to five certified biological samples, yielding a detection limit (3s, n = 10) of 0.04 µg g-1 based on a nominal sample mass of 0.5 g in a final volume of 50 mL. Calibration was achieved using simple aqueous standard solutions containing 0.1 mol L-1 NaOH. The procedure was efficient, with determined values lying in the range of 85-113 % of the certified values, showing good agreement at the 95% confidence level (t-test). The precision was fit for purpose, with relative standard deviations ranging from 7 to 9%. Organomercury species in solution were not detected; only Hg2+ in solution produces a signal. This new procedure provides for a simple approach to quantitation (and potentially speciation).

【 授权许可】

Unknown