中药材中重金属的测定

Determination of heavy metal in Chinese herbs

采用微波消解样品、石墨炉原子吸收分光光度法测定植物药材中铅和镉 ,冷原子吸收分光光度法测定植物药材中的汞。用此方法测定了美国NBS15 70标准参考物质菠菜粉 ,以及 2 3种 2 6 4份植物药材。铅、镉、汞方法的平均回收率分别为 95 8%、97 5 %、99 2 % ;检出限 (LOD)分别为 0 0 0 6mg kg、0 2 0 8μg kg、0 0 2 6 μg kg;定量限 (LOQ)分别为 0 0 19mg kg、0 6 94μg kg、0 0 87μg kg。此方法同样适用于食物样品中铅。

Microwave digestion system was used in digesting samples. Lead and cadmium were determined by graphite furnace atomic absorption spectrometry. Mercury was determined by cold vapor atomic absorption spectrometry. Standard reference material (NBS1570), spinach powder was used as analysis quality assurance in this method, and 264 Chinese herbs (23 species) and standard reference material were determined, and satisfactory results were obtained by using this method. Averages recovery of lead, cadmium and mercury is 95.0%, 97.5% and 99.2% respectively. Limit of detection (LOD) is 0.006mg/kg, 0.208 μg/kg and 0.026μg /kg respectively for lead, cadmium and mercury. Limit of quantity (LOQ) is 0.019mg/kg, 0.694 μg/kg and 0.087μg/kg respectively for lead, cadmium and mercury. This method is also suitable to determine lead, cadmium and mercury in food.