蛋膜固相萃取-石墨炉原子吸收光谱法测定酵母粉中的痕量镉

本文研究了蛋膜固相萃取-石墨炉原子吸收光谱法测定酵母粉中痕量镉的方法,实验中对蛋膜吸附镉的性能、洗脱剂的选择、洗脱液用量和干扰离子的影响等进行了探讨。结果表明在0.1～2.0mol/L氨水介质中,蛋膜能完全吸附镉。吸附的金属离子可以用0.48mol/L盐酸2mL完全洗脱下来。方法的检出限为0.0037ng/mL,回收率为97.8%～102%。该方法操作简单,准确性好,灵敏度高,适用于酵母粉和食品中痕量镉的分析,能获得满意的结果。

Determination of trace cadmium in yeast by solid phase extraction using eggshell membrane and graphite furnace atomic absorption spectrometry

A new method has been developed separation and preconcentration with biomaterial for the determination of trace cadmium based on eggshell membrane （ESM） prior to its determi- nation by graphite furnace atomic absorption spectrometry. The optimum experimental parameters for preconcentration of cadmium, such as ammonia medium, sample flow rate and volume, eluent and interfering ions, have been investigated. Cadmium could be quantitatively retained by ESM in the concentraton range of 0.1--2.0 mol/L ammonia solution, and then eluted completely with 0.48 mol/L HCl. The result showed that the detection limit of cadmium was 0. 0037 ng/ mL. The recovery rates of added standard were 98.7%-102.3%, the relative standard deviation is 1.26%--3.42%. The proposed method has been applied for the determination of trace amounts of Cd in yeast and food samples with satisfactory results.