水样经过滤后,直接采用高效液相色谱与电感耦合等离子体质谱联用法(HPLC-ICP-MS)进行分析。液相色谱分析中用Allmatia C18反相色谱柱作固定相,用调节至pH 7.5的1.2 g·L-1 L-半胱氨酸-5 mmol·L-1乙酸铵溶液和甲醇的混合液(98+2)作流动相淋洗,可使二价汞(Hg2+)、甲基汞和乙基汞在4.5 min内很好分离。用电感耦合等离子体质谱法分别测定各形态汞的含量。各形态汞的质量浓度在0.1~5.0 μg·L-1范围内与其峰面积呈线性关系。上述3种形态汞的检出限(3S/N)分别为0.027,0.012,0.013 μg·L-1,其相对标准偏差(n=11)分别为2.1%,1.7%,1.8%。以实际水样为基体对3种形态汞进行回收试验,测得回收率在91.7%~107%之间。

The filtered water sample was used directly for analysis by HPLC in hyphenation with ICP-MS. Allmatia C18 reversed-phase column was used as stationary phase, and mixtures of the mixed solution of 1.2 g·L-1 L-cysteine-5 mmol·L-1 ammonium acetate (predajusted to pH 7.5) and methanol (98+2) were used as mobile phase at a flow-rate of 1.0 mL·min-1 for elution in LC-separation. Inorganic mercury (Hg2+), methyl mercury and ethyl mercury were separated nicely within 4.5 min and determined by MS. Linear relationships between values of peak area and mass concentration of mercury were obtained in the same range of 0.1-5.0 μg·L-1. Detection limits (3S/N) found for the 3 species of mercury were 0.027, 0.012, 0.013 μg·L-1, and values of RSDs (n=11) were 2.1%, 1.7%, 1.8% respectively. Substantial water samples were used as matrixes, and recovery was tested by the standard addition method. Values of recovery found were in the range of 91.7%-107%.