两种基体改进剂对山药中铅元素的测定比较

Comparison of Determination of Lead in Dioscorea opposita by two Matrix Modiffers

比较了磷酸二氢铵,氯化铵两种基体改进剂对石墨炉原子吸收光谱法(GF-AAS)测定了山药中铅元素的含量的研究。两种基体改进剂测得山药中的Pb含量分别为39.2μg.mL-1(氯化铵)、40.0μg.mL-1(磷酸二氢铵),回收率分别为106.5%、95.57%,RSD为均小于5%。最佳测定方法为:以磷酸二氢铵作为基体改进剂,灰化温度为1100℃,原子化温度为1900℃时,用氘灯校正背景进行测定。

The investigation was compared to determine the contents of lead element in Dioscorea opposita by graphite gurnace atomic absorption spectroscopy（GF-AAS） with two matrix modifiers（ammonium dihydrogen phosphate and ammonium chloride）.The contents of lead in Dioscorea opposita were respectively 39.2μg·mL-1（chloride） and 40.0μg·mL-1（ammonium dihydrogen phosphate）,the recoveries were respectively 106.5% and 95.57% and the RSDs were less than 5%.The best method for the determination was follows：ammonium dihydrogen phosphate as matrix modifier,ashing temperature of 1100℃,atomic transition temperature of 1900℃ and correcting the background of deuterium lamp.