Logar Martina, Horvat Milena, Akagi Hirokatsu, Pihlar Boris
Jozef Stefan Institute, Jamova 39, 1000 Ljubljana, Slovenija,
Anal Bioanal Chem. 2002 Nov;374(6):1015-21. doi: 10.1007/s00216-002-1501-x. Epub 2002 Sep 25.
The purpose of the present work was to develop a simple, rapid, sensitive and accurate method for the simultaneous determination of inorganic mercury (Hg(2+)) and monomethylmercury compounds (MeHg) in natural water samples at the pg L(-1) level. The method is based on the simultaneous extraction of MeHg and Hg(2+)dithizonates into an organic solvent (toluene) after acidification of about 300 mL of a water sample, followed by back extraction into an aqueous solution of Na(2)S, removal of H(2)S by purging with N(2), subsequent ethylation with sodium tetraethylborate, room temperature precollection on Tenax, isothermal gas chromatographic separation (GC), pyrolysis and cold vapour atomic fluorescence spectrometric detection (CV AFS) of mercury. The limit of detection calculated on the basis of three times the standard deviation of the blank was about 0.006 ng L(-1) for MeHg and 0.06 ng L(-1) for Hg(2+)when 300 mL of water was analysed. The repeatability of the results was about 5% for MeHg and 10% for Hg(2+). Recoveries were 90-110% for both species.
本研究的目的是开发一种简单、快速、灵敏且准确的方法，用于同时测定天然水样中皮克每升（pg L⁻¹）水平的无机汞（Hg(²⁺)）和甲基汞化合物（MeHg）。该方法基于在对约300 mL水样进行酸化后，将MeHg和Hg(²⁺)的双硫腙配合物同时萃取到有机溶剂（甲苯）中，随后反萃取到Na₂S水溶液中，通过用N₂吹扫除去H₂S，接着用四乙基硼酸钠进行乙基化反应，在室温下于Tenax上预富集，进行等温气相色谱分离（GC）、汞的热解和冷蒸气原子荧光光谱检测（CV AFS）。当分析300 mL水样时，基于空白标准偏差的三倍计算得出的检测限，对于MeHg约为0.006 ng L⁻¹，对于Hg(²⁺)约为0.06 ng L⁻¹。结果的重复性对于MeHg约为5%，对于Hg(²⁺)约为10%。两种物质的回收率均为90 - 110%。
