高效液相色谱-电感耦合等离子体质谱法检测水产品中铅的形态

Speciation detection of lead in aquatic products by high performance liquid chromatography-inductively coupled plasma mass spectrometry

目的建立水产品中无机铅、三甲基铅、三乙基铅的高效液相色谱-电感耦合等离子体质谱(HPLC-ICP-MS)测定方法。方法样品经含1%EDTA-2Na的人工胃液微波提取、离心、过滤后,采用HPLC-ICP-MS联用仪,流动相为乙二胺四乙酸二钠-乙酸钠溶液(p H值=4.6)+甲醇(75+25,V/V),经C18反相色谱柱分离,ICP-MS检测,保留时间定性,外标法定量。结果 3种形态铅浓度为0 ng/ml^100 ng/ml时,线性相关系数(r)≥0.999,检出限均为0.01 mg/kg,无机铅、三甲基铅、三乙基铅的加标回收率分别为85.4%~95.7%、84.2%~90.3%和82.1%~88.1%。结论该方法操作简单、准确可靠、适用性强,适用于水产品中无机铅、三甲基铅和三乙基铅的检测要求。

Objective To establish a method of high performance liquid chromatography with inductively coupled plasma mass spectrometry method（ HPLC-ICP-MS） for the detection of inorganic lead,trimethyl lead and triethyl lead in aquatic products. Methods The samples were extracted by microwave with artificial gastric juice containing 1% EDTA-2 Na,centrifuged and filtrated. After connecting HPLC-ICP-MS and mobile phase consisted of ethylenediamine tetraacetic acid disodium-sodium acetate solution（ p H = 4. 6） ＋ methanol（ 75 ＋ 25,V/V）,the sample solution was separated by C18 reversed-phase column and detected by ICP-MS. Retention time was used to keep qualitative and the external standard method was used to quantify.Results Good linearity was obtained when the concentration of 3 speciations of lead were within 0 ng/ml-100 ng/ml,with the correlation coefficient（ r） ≥0. 999 and the detection limit of 0. 01 mg/kg. The recovery rates of inorganic lead,trimethyl lead and triethyl lead were within 85. 4%-95. 7%,84. 2%-90. 3% and 82. 1%-88. 1%,respectively. Conclusion The method is accurate and reliable with good applicability,which is simple to operate and suitable for testing requirements of inorganic lead,trimethyl lead and triethyl lead in aquatic products.