HPLC分离-氢化物发生-动态反应池-ICP/MS联用分析废水中砷形态

Fractionation of arsenic in waste water samples by HPLC-hydride generation-dynamic reaction cell-inductively coupled plasma mass spectrometry

采用高效液相色谱(HPLC)分离水中不同的砷物种,将串联进入氢化物发生(HG)-动态反应池(DRC)-电感耦合等离子体质谱仪(HPLC-HG-ICP-DRC-MS)系统进行检测,由此建立了废水中砷形态的分析方法,并探讨了最佳测试条件,最后对宁波部分地区废水中砷形态分布规律进行了初步探讨.结果表明,以0.04mo.lL-1L半胱氨酸(L-cys)、0.132mol·L-1NaBH4和体积分数2%的HCl作为氢化物发生器载液,以H2作为DRC-ICP-MS反应气,控制流速为1.5mL·min-1时,4种As物种都有最佳的氢化物发生效率,且其它金属离子对分析干扰可忽略不计,求得As(Ⅲ)、As(Ⅴ)、单甲基砷(MMA)、双甲基砷(DMA)的检测下限(3倍噪音)分别为0.003、0.001、0.002、0.004μg.L-1.此系统可成功测定废水中砷的形态.

A new method for determination of different species of arsenic in wastewater samples was established by HPLC separation followed by hydride generation-dynamic reaction cell-inductively coupled plasma mass spectrometry.Four species of As have the best hydrogen generation efficiency and the interference with 0.04 mol·L-1 L-cys-0.132 mol·L-1NaBH4-2% HCl as hydrogen generating agent.And H2 was employed as reaction gas and its flow rate was controlled of 1.5 mL·min-1.Under the optimum experimental conditions,the detection limit of As（Ⅲ）、As（Ⅴ）、MMA and DMA were 0.003,0.001,0.002 and 0.004μg·L-1（3δ）respectively.The method was successfully employed to determine different species of As in wastewaters from the Ningbo area and their distribution.