石墨炉原子吸收光谱法测定龟苓膏粉中铅含量

Determination of Pb Content in Guiling Jelly Powder by GFAAS

用干法消化处理样品,石墨炉原子吸收光谱法测定龟苓膏粉中铅含量。采用磷酸二氢铵和硝酸镁混合溶液作为基体改进剂,消除消化过程中产生的皂甙对测定结果的干扰。铅的质量浓度在5.0~40.0 ng/L范围内与其吸光度呈线性关系,检出限（3 s/k）为26 pg,相对标准偏差（n=7）为2.82%。应用此法测定龟苓膏粉样品,加标回收率在92.1%~99.0%之间。

The sample of Guiling Jelly-powder was pretreated by dry digestion,and lead content in the sample solution was determined by GFAAS.Mixed solution of NH4H2PO4 and Mg（NO3）2 was used as matrix modifier to offset interference of saponine produced during digestion.Linear relationship between values of absorbance and mass concentration of lead was obtained in the range of 5.0~40.0 ng/L,with detection limit（3s/k） of 26pg and RSD（n=7） of 2.82%.The values of recovery were in the range of 92.1%~99.0%.