石墨炉原子吸收光谱法同时测定牛奶中铅、铬

Graphite furnace atomic absorption spectrometric method for the simultaneous determination of lead and chromium in milk

建立了一种石墨炉原子吸收光谱法同时测定牛奶中铅、铬,牛奶样品,经高温灰化消解完全,然后使用浓度为0.5 mol/L硝酸溶液溶解灰分,待样液被混匀后上机检测。铅、铬检出限分别为0.005 mg/kg和0.01 mg/kg。在质量浓度为2~20 ng/m L范围内2种重金属元素标准曲线的线性关系良好,加标样品回收率为80.0%~96.7%,相对标准偏差为3.6%~10.5%。本方法样品处理简单、试剂用量少、检测结果准确度高、精密度好,各项技术指标能满足国内外法规的要求,可用于牛奶中铅和铬的确证检测。

A method for the simultaneous determination of lead and chromium in milk by graphite furnace atomic absorption spectrometry（GFAAS） was established. The milk samples were dissolved completely by high-temperature ashing, and then 0.5 mol/L nitric acid solution was used to dissolve ash, when the sample liquid is mixed evenly on the detection. The detection limits of lead and chromium were 0.005 mg/kg and 0.01 mg/kg. The calibration curves for the two heavy metal elements were linear in the mass concentration range of 2-20 ng/mL with correlation coefficients （r） than 0.995. The recoveries of fortified samples ranged from 80.0% ~96.8%,with the relative standard deviation of 3.6%~10.5%.The method has the advantages of simple sample processing, less reagent consumption, high accuracy and good pre- cision, and its performance can meet the requirements of the domestic and international legislations. It is suitable for the detection of lead and chromium residues in milk.