| Atomic fluorescence spectrometry is a new analysis technology between atomic absorption spectrometry and atomic emission fluorescence spectrometry. As an special analysis way, AFS offers extending good advantages in terms of high sensitivity, selectivity, convinence and accuracy, then it is widely used in trace-elemental analysis fields in recent years. With the continous and exciting development of the fields of Chinese Traditional Medicine, it is well known that Chinese Traditional Medicine plays a great role in the prevention and cure of some disease and makes a strong impact on our health. Especially , some trace nutritional elements in CTM such as copper, selenium are beneficial to human health . However , owing to the influence of the planting conditions , there are such poisionous elements such as mercury , arsenic in CTM . Then the contents of some poisionous elements in CTM should be controlled rigidly and it is crucial for our country to establish some simple, united, fast and valid analytical method, so we can keep the drugs' trait and take medicines safely.This paper is focused on the determination of trace mercury and arsenic, studied some factors, for example, the atomic fluorescence spectrometry was used in measuring trace mercury and arsenic in CTM, as follows:1. The determination of trace mercury in CTM was studieded by CVAFS. Thepretreatment ways of sample and the experimental conditions have been optimized respectively. Good linearity was observed over 0-2.0μg/L with a detection limit of 0.03μg/L and a correlation coefficient of 0.9996. The recovery was from 89% to 109%. Trace mercury in the standard reference substance was also determined according to this way and the result was in good agreement with certified value. We also studied the mercury contents in ten kinds of CTM sample by the working curve method and contrasted four kinds of them by addition plotting method. It proves to be simple, rapid, sensitive and convinent.2. It was developed for the determination of trace mercury in CTM by CVAFS . A high-pressure digestion way with HNO3-H2O2 system was used for the pretreatment. Good linearity was observed over 0-2.0ug/L with a detection limit of 0.03ug/L and a correlation coefficient of 0.9996. The recovery was from 90% to 110%. We also studied the mercury contents hi six kinds of CTM sample by the working curve method and contrasted four kinds of them by addition plotting method.3. A hydride generation atomic fluorescence spectrometry method has been developed for the determination of trace mercury in CTM . A high-pressure digestion way using HNO3- H2O2 system was applied for the pretreatment of samples and the interval flow procedure was used. The experimental conditions and instrumental operation parameters such as KBHU concentration, flow rate of the carrier and shield gas , currents of lamp and height of atomic oven which affect the determination had been optimized respectively. There was a good linear relationship between the fluorescence intensity and mercury concentration in the range of 0~12μg/l with a correlation coefficient of 0.9999 , while detection limit was 0.02lμg/1 and the recovery from 89.2% to 11.6%. Trace mercury in the standard reference substance peach leaf (GBW08501) was also determined according to this way and the results were in good agreement with certified value , the coefficient of variation was not more than 1.34% simultaneously . We also studied the mercury contents hi eleven lands of CTM sample by the working curve method and contrasted five kinds of them by addition plotting method.4. A hydride generation atomic fluorescence spectrometry method had been developed for the determination of trace arsenic in CTM. A digestion system using HNO3 - H2O2 in the high-pressure was applied for the pretreatment of the samples . The experimental conditions had been optimized respectively . Under the optimum conditions , there was a good linear relationship between the fluorescence intensity and arsenic concentration hi the range of 0~80ug/l...
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