石墨炉原子吸收光谱法测定柑橘皮中铅

Determination of Trace Lead in Citrus Peels by Graphite Furnace Atomic Absorption Spectrometry

采用加入基体改进剂-石墨炉原子吸收光谱法测定柑橘皮样品中的痕量铅。应用塞曼效应消除背景干扰,以20 g/L的磷酸二氢铵(NH4H2PO4)为基体改进剂,灰化温度为500℃,原子化温度为1900℃。试样消解分别采用了湿法消化法和干法灰化法。铅的质量浓度在0～110μg/L范围内与其吸光度呈线性关系,湿法消化法和干法灰化法的检出限(3 s)分别为12.26μg/kg和3.803μg/kg。应用此建立的石墨炉原子吸收光谱法分析了几种柑橘皮试样中铅,方法快速简便、结果比较准确。

The determination of trace lead in citrus fruits was established by matrix modifier-graphite furnace atomic absorption spectrometry. The Zeeman correction was used to avoid the interfere of background, 20 g/L NH4H2PO4 was used as matrix modifier, and temperatures for ashing and atomization were 500℃ and 1900℃. The wet digestion and dry ashing method were used to handle samples. Linear relationship between values of absorbance and mass concentration of Pb was obtained in the range of 0-110 μg/L. The wet digestion and dry ashing method detection limits （3 s） respectively was 12.26μg/kg and 3.803/ag/kg. The proposed method was used in the analysis of several citrus peels. The method is rapid and accurate.