冷原子吸收法测定人发和中成药中汞

Determination of Mercury in Hair and Traditional Chinese Medicines by Cold Vapour Atomic Absorption Spectrometry

本文以空气作载气考察了各种实验条件对冷原子吸收法测定汞的影响 ,在最佳实验条件下 ,汞的灵敏度为 1 1μg·L-1,检出限为 0 5 μg·L-1,校正曲线线性范围 0～ 4 0 μg·L-1。采用密封式压力消解样品 ,以HNO3、H2 SO4和H2 O2 ( 4 + 1+ 1)为氧化剂 ,SnCl2 为还原剂 ,成功地用于人发标样和不同种类中成药中汞的测定 ,相对标准偏差分别为 3 2 % ,1 5 %和 0 2 4 % ,回收率 94 6%～ 10 2 % ,用方便节省的空气代替高纯氩气作载气完全可行。

The effects of various experimental conditions on the determination of mercury by cold vapour atomic absorption spectrometry were investigated. Under the optimum conditions, the detection limit of mercury was 0.5 ng(.)mL(-1), and the sensitivity was 1.1 ng(.)mL(-1). The calibration curve was linear in the range of 0-40 ng(.)mL(-1). The analytical procedure of mercury by pressure dissociation method was established by using HNO3, H2SO4 and H2O2(4+1+1) as oxidant, SnCl2 as reductant in acid medium. The analysis method was successfully applied to the determination of mercury in certified reference material of hair and traditional Chinese medicines, the relative standard deviations were 3.2%, 1.5% and 0.24% respectively. The recovery of mercury was 94.6% - 102%. The results obtained were satisfactory. Air can been used as carrier gas instead of high purity argon.