原子吸收光谱法测定冬凌草中的矿物元素

用原子吸收光谱法测定冬凌草中影响人体健康的8种矿物元素Cu、Zn、Fe、Mn、Ca、Mg、Se和Pb的含量。样品经硝酸-高氯酸消解后,采用偏振塞曼效应扣除背景吸收,用火焰原子吸收光谱法检测积分吸收测定冬凌草中Cu、Zn、Fe、Mn、Ca和Mg的含量,用石墨炉程序升温原子吸收光谱法检测峰值吸收测定Se和Pb含量。测定结果显示:该方法的精密度RSD为1.22%—5.64%;加标回收率为95.0%—110.5%;8种矿物元素的检出限(P=95%,α=0.5)分别为Cu0.034、Zn0.0028、Fe0.031、Mn0.110、Ca0.367、Mg0.132mg·mL-1,Pb1.40μg.L-1和Se1.86μg.L-1。该方法简便快速、灵敏、准确,适用于中药冬凌草中矿物元素含量的测定。

Determination of Mineral Elements in Rabdosia Rubescens (Hemsl.) Hara by Atomic Adsorption Spectrophotometry

The mineral elements contents of copper,zinc,iron,manganese,calcium,magnesium,selenium and lead in the Rabdosia rubescens effecting human healthiness were determined by atomic absorption spectrophotometry.After the samples were digested by HNO3 and HClO4,the contents of Cu,Zn,Fe,Mn,Ca and Mg were determined by flame atomic absorption spectroscopy with the measurements of integral area of signals,and the measurement of Pb and Se were based on peak area of transient signals,while background signal correction was based on Zeeman effect.The results showed that the relative standard deviation of the method was 1.22%—5.64%;and the recoveries were estimated to be 95.0%—110.5%.The limits of detection were Cu 0.034,Zn 0.0028,Fe 0.031,Mn 0.110,Ca 0.367,Mg 0.132mg·L-1,Pb 1.40μg·L-1 and Se 1.86μg·L-1（P=95%,α=0.5）.The methods are simple-accurate and high-specificity,and can be used for determination of mineral elements in Rabdosia rubescens（Hemsl.）Hara.Hara holds high nutritional value,and has vast prospects for development and applications.