自制四氧化三锰纳米粒子固相萃取-电感耦合等离子体质谱法测定蔬菜中铅和铜

ICP-MS Determination of Lead and Copper in Vegetables with Solid Phase Extraction of Self Made Nanosized Mn_3O_4

采用自制四氧化三锰纳米粒子固相萃取-电感耦合等离子体质谱法测定蔬菜中铅和铜的含量。优化的固相萃取条件如下:(1)样品溶液的pH为4.0;(2)样品溶液的流量为1.0mL·min^(-1);(3)四氧化三锰纳米粒子的用量为50mg;(4)洗脱剂为3mol·L^(-1)盐酸溶液,用量为2mL;(5)样品溶液的体积为20mL。铅和铜的线性范围依次为0.01~5.0,0.02~1.0μg·L^(-1),检出限(3s/k)依次为4,8ng·L^(-1)。加标回收率为80.0%~108%,测定值的相对标准偏差(n=7)为0.94%~3.2%。

ICP-MS was applied to the determination of lead and copper in vegetables with solid phase extraction of self made nanosized Mn3O4. The optimized conditions of solid phase extraction were as follows： （i） pH of the sample solution was 4. 0; ② flow rate of the sample solution was 1.0 mL·min^-1③ amount of nanosized Mn3O4 was 50 rag; ④ the elumlt was 3 mol·L^-1 HCl solution and its amount was 2 mL; ⑤ volume of the sample solution was 20 mL. Linearity ranges of lead and copper were found in the ranges of 0. 01--5.0, 0. 02--1.0 t^g ~ L-1 respectively, with detection limits （3s/k） of 4, 8 ng ·L^-1 respectively. Values of recovery found by standard addition method were in the range of 80. 0%- 108%, and values of RSDs （n：7） were in the range of 0. 94%-3. 2%.