Krata Agnieszka Anna
Faculty of Chemistry, University of Warsaw, 1 Pasteura St., Warsaw, 02-093, Poland.
Department of Environmental Chemistry, Faculty of Chemistry, University of Lodz, 163 Pomorska St., Łódź, 90-236, Poland.
J Sep Sci. 2022 Sep;45(18):3624-3634. doi: 10.1002/jssc.202200347. Epub 2022 Aug 21.
Assignment of inorganic mercury and methyl mercury mass fractions at an ultratrace level in soil certified reference material EnvCRM 03 with a complex matrix composition was undertaken. Inorganic mercury and methyl mercury contents by species-specific isotope dilution inductively coupled plasma mass spectrometry with on-line high-performance liquid chromatography or with classical off-line chromatography were established. Different extraction protocols: sequential extraction ((1) H SO /KBr/CuSO ; (2) dichloromethane; (3) Na S O ) or one-step extraction (diluted HCl) in solid-liquid systems were verified. Sequential extraction allowed quantification and separation of inorganic mercury and methyl mercury on HPLC column in one chromatographic run and were found to be (316 ± 10) μg/kg (U = 3.2%, k = 2) and (0.53 ± 0.02) μg/kg (U = 3.8%, k = 2), respectively. Extraction by diluted HCl and application of classical off-line chromatography led to the separation of methyl mercury from predominant inorganic mercury form and was found to be (0.54 ± 0.03) μg/kg (U = 5.4%, k = 2). To the best-obtained literature knowledge, there was no available soil material aimed for speciation analysis of inorganic mercury and methyl mercury so far. Both developed analytical methodologies were found to be equally sensitive and could be successfully applied for mercury species determination in samples with the complex matrix.
对具有复杂基质组成的土壤标准物质EnvCRM 03中超痕量水平的无机汞和甲基汞质量分数进行了测定。采用在线高效液相色谱或经典离线色谱的物种特异性同位素稀释电感耦合等离子体质谱法确定了无机汞和甲基汞的含量。对固液体系中的不同萃取方案进行了验证：顺序萃取（(1) H₂SO₄/KBr/CuSO₄；(2) 二氯甲烷；(3) Na₂S₂O₃）或一步萃取（稀HCl）。顺序萃取可在一次色谱运行中对HPLC柱上的无机汞和甲基汞进行定量和分离，结果分别为(316 ± 10) μg/kg（U = 3.2%，k = 2）和(0.53 ± 0.02) μg/kg（U = 3.8%，k = 2）。用稀HCl萃取并应用经典离线色谱法可将甲基汞与主要的无机汞形态分离，结果为(0.54 ± 0.03) μg/kg（U = 5.4%，k = 2）。据目前所获得的最佳文献知识，迄今为止尚无用于无机汞和甲基汞形态分析的土壤材料。发现这两种开发的分析方法同样灵敏，可成功应用于复杂基质样品中汞形态的测定。
