微波消解-石墨炉原子吸收光谱法分析中药中微量元素

采用石墨炉原子吸收光谱法(GFAAS)测定了中药中铜、 铁和锌的含量. 以磷酸二氢铵作为基体改进剂， 对基体改进剂的用量、 灰化温度、 原子化温度等实验参数进行了选择和优化. 实验结果表明， 加入基体改进剂后不仅能提高测定的灵敏度， 还能有效地消除共存离子的干扰. 在选定的实验条件下， 利用标准加入法分析测定了中药当归(Ra dix angelicae sinensis)、 槐花(Flos sophorae)、 桑寄生(Herba taxilli)、 罗布麻叶 (Folium apocyni veneti)和黄芩(Radix scutellarae)等中药中的铜、 铁和锌的含 量， 回收率为90%~110%， 方法的相对标准偏差小于5%. 该法快速、 可靠， 为中药中微量元素的测定提供了一种简便的方法.

Determination of Trace Elements in Traditional Chinese Medicines by Microwave Digestion-graphite Furnace Atomic Absorption Spectrometry

A method for the determination of trace elements in traditional Chinese medicines by graphite furnace atomic absorption spectrometry(GFAAS) is described.The matrix modifier used in this work was NH_4H_2PO_4.The effects of matrix quantity,ashing temperature and atomization temperature were investigated.Matrix modifier NH_4H_2PO_4 can not only improve the sensitivity of determination but also eliminate the matrix effect.Under the optimum experimental conditions,copper,iron and zinc in traditional Chinese medicines such as radix angelicae sinensis,flos sophorae,herba taxilli,folium apocyni veneti and radix scutellarae were determined.The recoveries are between 90% and 110%,the relative standard deviation is less than 5%,and the experimental results are satisfactory.This method is rapid and reliable.It provides a simple method for the determination of trace elements in traditional Chinese medicines.