盐酸超声提取-高分辨电感耦合等离子体质谱法测定食用植物油中11种微量金属元素

Determination of 11 Trace Metel Elements in Edible Vegetable Oil by High-Resolution Inductively Coupled Plasma Mass Spectrometry after Ultrasonic Extraction with Hydrochloric Acid

提出了盐酸超声提取-高分辨电感耦合等离子体质谱法(HR-ICP-MS)快速测定食用植物油中铝、钡、镉、铜、铁、镁、锰、镍、铅、钒、锌等微量金属元素的方法。取2.0 g食用植物油样品,置于50 mL塑料离心管中,加入800μL ICP溶剂油,于旋涡混匀器上充分混匀,加入10 mL 2.0 mol·L^(-1)盐酸溶液,于70℃超声30 min,冷却。以转速10000 r·min^(-1)离心5 min,在水相与有机相分离后,收集水相,采用HR-ICP-MS测定其中11种元素含量,待测同位素^(51)V、^(56)Fe、^(27)Al、^(63)Cu、^(24)Mg、^(55)Mn、^(60)Ni、^(66)Zn选择中分辨率模式,而^(137)Ba、^(111)Cd和^(208)Pb选择低分辨率模式。结果表明:11种元素的质量浓度在100μg·L^(-1)以内与对应的信号强度呈线性关系,检出限(3s)为0.012~0.173μg·L^(-1);按照标准加入法对食用植物油进行回收试验,回收率为86.9%~107%,测定值的相对标准偏差(n=7)为1.1%~4.9%;方法用于分析3种植物油样品,本方法测定值与标准方法的测定值基本一致。

A method for the rapid determination of trace metel elements including aluminum,barium,cadmium,copper,iron,magnesium,manganese,nickel,lead,vanadium,and zinc in edible vegetable oil by high-resolution inductively coupled plasma mass spectrometry(HR-ICP-MS)after ultrasonic extraction with hydrochloric acid was proposed.2.0 g of edible vegetable oil sample was taken into a 50 mL-plastic centrifuge tube,and 800μL of ICP solvent oil was added.After thoroughly mixing on a vortex mixer,10 mL of 2.0 mol·L−1 hydrochloric acid solution was added,and the mixture was sonicated at 70℃for 30 min and cooled.The mixture was centrifuged at a rotational speed of 10000 r·min^(-1)for 5 min.After separating the aqueous phase from the organic phase,the aqueous phase was collected,in which 11 elements were determined by HR-ICP-MS,with medium resolution mode for isotopes to be tested of^(51)V,^(56)Fe,^(27)Al,^(63)Cu,^(24)Mg,^(55)Mn,^(60)Ni,and^(66)Zn,and low resolution mode for^(137)Ba,^(111)Cd,and^(208)Pb.As shown by the results,linear relationships between the corresponding response intensity and mass concentrations of 11 elements were found within 100μg·L^(-1),with detection limits(3s)of 0.012-0.173μg·L^(-1).Test for recovery was made on edible vegetable oil sample by standard addition method,giving results in the range of 86.9%-107%.RSDs(n=7)of the determined results were in the range of 1.1%-4.9%.The method was applied to analysis of 3 edible vegetable oil samples,and the determined values of this method were basically consistent with those of the standard methods.