石墨炉原子吸收光谱法测定生活日用品中铅、镉、钴

GF-AAS Determination of Lead,Cadmium and Cobalt in Daily Necessities

日用品样品置于微波消解罐中,用硝酸及过氧化氢在WP 200 LG微波炉中消解。在所得样品溶液中加入钼酸铵、磷酸氢二铵作基体改进剂后直接进样进行石墨炉原子吸收光谱法测定。在优化的试验条件下,测得铅、镉、钴溶液的吸光度与质量浓度分别在100,50及20μg·L-1以内呈线性关系,方法的检出限(3S/N)分别为6.25,0.50,0.65μg·L-1。对5种样品分别加入铅、镉、钴的标准溶液进行回收试验,结果分别为80%～130%,80%～110%,92%～112%。

Samples of daily necessities were digested in PTFE vessel with HNO3 and H2O2, and heated in WP 200 LG microwave oven under prescribed program. Ammonium molybdate and diammonium hydrogen phosphate solutions were added as matrix modifiers to the sample solution obtained. Under the optimized experimental conditions, linear relationships between values of absorbance and mass concentration of the 3 elements were obtained in the ranges within 100μg·L^-1 for lead, within 50μg·L^-1 for cadmium and within 20 μg·L^-1 for cobalt. Values of detection limit （3S/N） obtained were 6. 25, 0. 50 and 0. 65μg·L^-1 respectively. Tests for recovery were made for the 3 elements by standard addition method using 5 different kinds of samples as matrix, giving results of recovery in the ranges of 80%-130%, 80%-110% and 92%-112% respectively.