微波消解-原子荧光光谱法测定中药材中痕量镉

Determination of trace amount cadmium in Chinese herbal medicine material with microwave digestion and VG-AFS

目的:建立用微波消解-原子荧光光谱法测定中药材中痕量镉的方法。方法:药材经微波消解后,以二硫腙三氯甲烷溶液、氨基磺酸铵溶液、硫酸钾和氯化钡溶液为掩蔽剂,以硫脲和钴离子溶液为还原催化剂,用原子荧光光谱法对药材中的痕量镉进行测定;同时考察载流盐酸、硼氢化钾浓度及共存元素的干扰。结果:本法线性范围为0.0～4.0ng·mL^(-1)、相关系数大于0.9990,最低检出浓度为0.014 ng·mL^(-1),回收率均在80%以上。结论:本法具有操作简单、灵敏度高、重现性好等优点,能满足痕量镉的测定要求。

Objective：To determine trace amount cadmium in Chinese herbal medicine material with the microwave digest and VG- AFS. Methods：The samples were digested with the microwave,dithizone - trichloromethane, ammonnium sulfamate, potassium sulfate and barium chloride were used for masking some disturbing elements, sulfourea and Co^2＋ were used as reducing agent, and VG - AFS was applied to determine trace amount cadmium in Chinese herbal medicine material. The effect of concentration of hydrochloric acid, potassium borohydride in carrier flow and coexistence interference chemical element on the determination were studied. Results ：The cadmium content showed linearity in the range of 0. 5 - 4. 0 ng· mL^ - 1, the linear correlation coefficient was higher than 0. 9990. The detection limit was 0. 014 ng· mL^-1, the recovery rate of spiked samples ranged above 80%. Conclusion-The method is simple, sensible, accurate and reproducible, and applied for quality control of cadmium in Chinese herbal medicine.