建立了高效液相色谱与原子荧光光谱联用测定汞化合物形态的分析方法.实验对淋洗液组分浓度、氧化剂和还原剂浓度、载气流速及紫外消解管长度等操作条件进行了优化,获得了令人满意的分析结果.在优化的分离检测条件下,20 μg/L的汞化合物标准溶液平行7次进样分析,甲基汞、无机汞和乙基汞的色谱峰高的相对标准偏差(RSD)分别为2.0%、2.9%和2.4%;3种汞化合物的线性范围为10~1000 μg/L,25 μL进样检出限分别为3、2和4 μg/L.用建立的方法测定了脉红螺样品中甲基汞的含量,甲基汞和乙基汞的加标回收率分别为90%和92%.
An interface technique coupled high performance liquid chromatography with atomic fluorescence spectrometry for mercury speciation analysis is established. The separation and determination conditions of methylmercury, inorganic mercury and ethylmercury on high performance liquid chromatography coupled atomic fluorescence detector are discussed. In order to obtain satisfying chromatogram, operational conditions such as mobile phase composition, concentration of oxidant and reducing agent, flow rate of carrier gas, length of UV tube and so on were optimized. Under the optimized conditions, the relative standard deviations (RSD) for the determination of methyl-, ethyl- and organic mercury are 2.0%, 2.4% and 2.9% ( n = 7 ), respectively. The linear range for all the species is between 10 and 1000 μg/L, while the detection limits are: 3 μg/L, 2 μg/L and 4 μg/L respectively. The proposed method has been applied for determination of methylmercury in Rapana Venosa sample and the recovery for methylmercury and ethylmercury is 90% and 92%, respectively.