电热解-塞曼原子吸收光谱法快速测定南药中总汞

Rapid determination of total mercury in south China herbal medicine by pyrolysis-Zeeman atomic absorption spectrometry

建立了热解-塞曼原子吸收光谱法测定南药中总汞的快速分析方法。样品冻干后,利用热解技术直接测定南药固体样品中的汞,并利用塞曼效应对杂质信号进行背景校正,提高了测量的灵敏度。方法检出限为0.96μg·kg^(-1),定量限为3.18μg·kg^(-1),线性范围为0~15ng,线性相关系数r^2=0.9999。对4种标准物质进行分析,相对标准偏差(RSD)为2.4%~4.7%,表明该方法具有较高的准确度和精密度。经对实际样品分析,8种南药样品汞含量为5.22~25.30μg·kg^(-1),加标回收率90.6%~106.6%,RSD为1.1%~5.7%,该测定结果与热分解齐化原子吸收光谱法和微波消解-ICP-MS的检测结果基本一致。该方法准确、可靠,定量限满足《中国药典》(2015版)中的汞限量要求,可用于南药质量控制。

The samples were dried prior to detection. The sensitivity of method was considerably improved by Zeeman background correction technique. The method showed good linearity （ r2 =0. 9999） in the range of 0 to 15 ng using aqueous mercury standard solutions. The detection limit was 0. 96μg·kg-1 and quantification （LOQs） limit was 3.18μg·kg-1. The method was validated by analysis of four certified reference material samples, RSDs ranged from 2.4% to 4.7%, （n=5）. The total mercury contents in eight types of south China herbal medicine samples were from 5.22 to 25.30μg·kg-1 , achieving spike recoveries were between 90. 6% and 106.6%, RSD was 1.1%-5.7%. The results were consistent with those obtained by thermal decomposition atomic absorption spectrophotometry and microwave digestion- ICP-MS methods. The method can meet the requirement of mercury limit in Chinese Pharmacopoeia （2015 Edition）, and can be used for the quality control of south China herbal medicine.