微波消解样品-石墨炉原子吸收光谱法测定食品添加剂中铅和镉含量

GF-AAS Determination of Lead and Cadmium in Food Additives with Microwave Assisted Sample Digestion

摘要: 提出了石墨炉原子吸收光谱法测定食品添加剂中铅和镉含量的方法.样品用硝酸及过氧化氢作溶剂,使用微波消解的方法处理.以磷酸二氢铵为基体改进剂,铅和镉灰化温度分别为600 ℃和400 ℃,原子化温度分别为2 100 ℃和1 800 ℃.在优化的试验条件下,测得铅和镉相对标准偏差(n=6)分别为2.8%~6.5%和2.4%~5.3%,7种食品添加剂中铅和镉的回收率在94%~102%和96%~103%之间.

Abstract: A method of GF-AAS for the determination of Pb and Cd in food additives was proposed.The sample was treated by microwave digestion with HNO3 and H2O2.Ammonium dihydrogen phosphate was used as a matrix modifier.The ashing and the atomization temperature for Pb was 600 ℃ and 2 100 ℃ and for Cd was 400 ℃ and 1 800 ℃ respectively.Under the optimum conditions,values of RSD′s (n=6) was found in the range of 2.8%-6.5% for Pb and 2.4%-5.3% for Cd,with recovery in the range of 94%-102% for Pb and 96%-103% for Cd.