氢化物发生-原子荧光光谱法测定中药中的痕量砷

Determation of Trace Arsenic in Chinese Traditional Medicine by Hydride Generation-Atomic Fluorscence Spectrometry

建立了氢化物发生-原子荧光光谱法测定中药中痕量砷的测定方法。应用AFS-2202a型双道原子荧光分光光度计和断续流动的氢化物发生技术,研究了不同湿法消解体系对测定结果的影响,选用HNO3-H2O2体系消解中药样品。同时,研究了硼氢化钾浓度、屏蔽气和载气流量、灯电流、原子化器高度等因素对测定结果的影响。在选定实验条件下,砷的检出限为0.069μg/L,桃叶(GBW08501)验证结果与推荐值一致,6次测定结果相对标准偏差为2.46%。该方法简便、快速、灵敏、准确,对实际中药样品进行测定得到了满意的结果。

Hydride generation atomic fluorescence spectrometry method was developed for the determination of trace arsenic in traditional Chinese medicines.High-pressure digestion using HNO3-H2O2 system was applied for the pretreatment of traditional Chinese medicine samples and the interval flow precedure was used.The influence on the determination of trace arsenic by the different wet-digestion systems was studied.The experimental conditions and instrumental operation parameters such as KBH4 concentration ,flow rate of the carrier and shield gas,currents of lamp and height of atomic oven which affect the determination were optimized respectively.Under the optimum conditions,the detection limit is 0.069μg/L.Trace arsenic in the standard reference substance peach leaf （GBW08501） was also determined according to this way and the results of six times are in good agreement with certified value ,the coefficient of varation is not more than 2.46%.This method is simple,rapid,sensitive,convinent and accurate,so it can be successfully used for the determination of trace arsenic in traditional Chinese medicines.