Evaluation of a new electrolytic cold vapor generation system for mercury determination by AFS.
In this study we firstly report a new electrolytic cold vapor generation system for mercury determination on Pt/Ti cathode in the presence of organic acid catholyte. Comparing with the traditional inorganic acid, formic acid increased the signal intensity of Hg vapor from electrolytic generation on Pt cathode and reduced the impact of cathode erosion on the stability of signal intensity. Moreover, formic acid has better interference tolerance. The introduction location for carrier gas is probably the most important factor that influences the signal intensity of Hg from electrolytic vapor generation. The effects of the electrolytic conditions and interference ions on the ECVG have been studied. Under the optimized conditions, the detection limit (3 sigma) of Hg (II) in aqueous solutions is 1.4 ng L(-1); a relative standard deviation of 2.3% for 1 microg L(-1) Hg was obtained. The accuracy of this method was verified by the determination of mercury in the certified reference materials. This system has been applied satisfactorily to the determination of Hg in Traditional Chinese Medicines samples.
Zhang
Wang-bing
WB
Department of Applied Chemistry, Anhui University of Technology, Maanshan, Anhui 243002, PR China. zhangwb@ahut.edu.cn
Su
Zhao-fei
ZF
Chu
Xiang-feng
XF
Yang
Xin-an
XA
D004365:Drugs, Chinese Herbal / Q000032:analysis*; D004566:Electrodes; D004572:Electrolysis / Q000295:instrumentation*; D004867:Equipment Design; D005561:Formates / Q000737:chemistry; D005740:Gases / Q000032:analysis; D057230:Limit of Detection; D008628:Mercury / Q000032:analysis*; D010084:Oxidation-Reduction; D013050:Spectrometry, Fluorescence / Q000379:methods*; D014835:Volatilization
D004365:Drugs, Chinese Herbal; D005561:Formates; D005740:Gases; C030544:formic acid; D008628:Mercury