微波消解-石墨炉原子吸收光谱法测定菜籽及饼粕中铅和镉

Determination of Lead and Cadmium in Rapeseed and Rapeseed Meal with Microwave Digestion by Graphite Furnace Atomic Absorption Spectrometry

目前菜籽及饼粕的综合利用越来越受到人们的重视,同时重金属的污染问题也日益引起人们广泛的关注,因此测定菜籽及饼粕中铅和镉的含量具有十分重要的意义。文章研究了微波消解溶剂、微波时间和压力对样品消解效果的影响,优化了石墨炉原子吸收光谱法测定条件,建立了一种快速检测菜籽及饼粕中铅、镉含量的有效方法。研究表明,铅、镉的检出限分别为2.172μg·L-1(54.30ng.g-1)、0.243μg·L-1(6.075ng.g-1),其线性范围分别为0～100μg·L-1,0～8μg·L-1;样品测定回收率在80.8%～110.7%之间,RSD小于5.3%。该法具有检出限低、灵敏度高、快速、准确的特点,用于实际样品测定的结果令人满意。

Comprehensive utilization of rapeseed and rapeseed meal has been increasingly emphasized, and eontaminative problems of heavy metal have been attracting great attention, so it is of quite important significance to determine the contents of Pb and Cd. An effective method was developed for the rapid determination of Pb and Cd in rapeseed and rapeseed meal. Digestive dissolvent, time and pressure were discussed for sample preparation by rnierowave digestion technique, and the optimum condition of determination by GFAAS was studied. The determination limits were 2. 172 and 0. 243μg·L^-1 , and the linear arranges were 0-100μg·L^-1 and 0-8μg·L^-1 for Pb and Cd, respectively. The recoveries were from 80.8% to 110. 7%. The RSD of determination was lower than 5.3%. The method offers traits of low detection limit, high sensitivity, speediness and exactness, and was applied to the determination of Pb and Cd in samples with satisfactory results.