阴/阳离子交换色谱-电感耦合等离子体质谱法分析鱼和贝类海产品砷的形态

Analysis of Arsenic Speciation in Sea Fish and Shellfish by Anion/Cation Exchange High Performance Chromatography Coupled with Inductively Coupled Plasma-Mass Spectrometry

采用阴(Hamilton PRP-X100柱)阳(Dionex Ionpac CS-10柱)离子交换色谱-电感耦合等离子体质谱联用技术,分别以pH 10.3的20 mmol/L NH4HCO3和pH 2.0的5 mmol/L吡啶溶液为流动相,建立了三价砷As(Ⅲ)、五价砷As(Ⅴ)、一甲基砷酸(MMA)、二甲基砷酸(DMA)、砷甜菜碱(AsB)、砷糖(PO4,OH,SO3,SO4)砷形态的分析方法。采用微波消解法和超声溶剂提取法对我国不同海域9种鱼和贝类海产品进行前处理,对砷含量及其化学形态进行分析。实验表明,鱼和贝海产品主要砷形态为砷甜菜碱AsB,其含量占可提取砷的42.8%～99.4%,大多数贝类样品含有砷糖PO4、砷糖OH,其含量分别占可提取砷的32.5%～57.1%和1.4%～3.3%,少数样品含有DMA,其含量分别占可提取砷的5.7%～25.0%,所有样品无机砷的浓度均低于可提取砷的2.0%。在鱼和贝类海产品中,含砷化合物主要是毒性较低的有机砷,不会对人的健康带来危害。

The separation of arsenic compounds,including As（Ⅲ）,As（Ⅴ）,monomethylarsonate（MMA）,dimethylarsonate（DMA）,arsenobetaine（AsB）,arsenosugar PO4,arsenosugar OH,arsenosugar SO3 and arsenosugar SO4 were carried out in Hamilton PRP-X100 anion-exchange column with a mobile phase of 20 mmol/L NH4HCO3（pH 10.3） and on a Dionex Ionpac CS-10 cation-exchange column with a mobile phase of 5 mmol/L pyridinium（pH 2.0） for their analysis by ICP-MS.Total content of As and its different species of eight types of fish and shellfish in microwave-assisted digestion and ultrasonic solvent extraction were examined.The results showed that main components in all of the extracted fish and shellfish samples were arsenobetain（42.8%-99.4%）,while arsenosugar PO4 and arsenosugar OH were detected in most extracted shellfish samples（32.5%-57.1%,1.4%-3.3%）,DMA was detected in a few extracted samples（5.7%-25.0%）.In contrast,no inorganic arsenic in fish and shellfish samples occurred at levels below 2.0%.