HG—AFS法测定植物和中药中的痕量砷

应用AFS-930型原子荧光分光光度计，采用高压溶样的消解方式，对仪器条件进行了探索优化，建立了氢化物发生-原子荧光法（HG—AFS）测定植物和中药中痕量砷的测定方法。砷的工作曲线在0—10μg·L^-1范围内线性良好，相关系数为0．9999。检出限为0．008μg·L^-1。在选定实验条件下，测定了国家标准物质杨树叶（GBW07604）和茶叶（GBW07605）中As含量，其测定值与推荐值吻合地很好，方法的相对标准偏差〈3％，结果令人满意。采用这种方法对几种中药和植物进行了测定，回收率在97％～106％。

Determination of Trace Arsenic in Plant and CTM by HG-AFS

A hydride generation atomic fluorescence spectrometry method was developed for the determination of trace arsenic. A digestion system using HNO3 -H2O2 under high pressure was applied for the pretreatment of the samples. The experimental conditions were optimized. Under the optimum conditions, there was a good linear relationship between the fluorescence intensity and arsenic concentration in the range of 0 -10μg · L^-1 with a correlation coefficient of 0. 9999, while the detection limit was 0. 008μg · L^-1 Trace arsenic in the standard reference substance （GBW07604 and GBW07605 ） was determined incording this way and the results for four times of analysis were in good agreement with certified value. The relative standard deviation was 〈3%. The authors also studied the arsenic contents in four kinds of plant and Chinese Traditional Medicine（CTM） by the working curve method. The results were satisfactory and the recovery percent is between 97% and 106%.