稀酸温和提取直接进样快速测定大米中镉含量  

Rapid Direct Sampling Detection of Cd in Rice Using Diluted Acid Extraction

作　　者：周明慧[1] 王松雪[1] 伍燕湘[1] 

机构地区：[1]国家粮食局科学研究院,北京100037

出　　处：《中国粮油学报》2015年第2期97-102,共6页Journal of the Chinese Cereals and Oils Association

基　　金：粮食公益性行业科研专项(201313005-2);中央级公益性科研院所基本业务费(ZX1301)

摘　　要：建立了常温条件下利用稀酸温和提取直接进样石墨炉原子吸收光谱法快速测定大米中镉的方法。考察了粉碎粒径、硝酸浓度、提取时间、固液比例等因素的影响，优化了灰化温度和原子化温度等仪器条件，确定了大米中镉元素测定的最佳条件。结果表明，常温条件下采用稀硝酸提取大米中的镉元素，浸提率在98．5％～100％之间，加标回收率达到93．0％～100％之间，精密度小于5％，方法的检出限和定量限分别为0．016μg／L和0．048μg／L，样品处理时间可缩短至20min内，与经典的微波消解原子吸收光谱法和微波消解ICP—MS法比较，各类大米中镉元素的测定值无显著性差异（P〉0．05）。The method for rapid determination of Cd in rice was established under normal temperature using diluted acid mild extraction and direct sampling coupled with graphite furnace atomic absorption spectrophotometer. Some factors were observed including the grain size, nitric acid concentration, extraction time, solid and liquid proportion and the instrument conditions were optimized including ashing temperature and atomizing temperature etc.. The best examination condition of Cd in rice was achieved. Results show that, the exaction rate of Cd in rice by dilu- ted acid was between 98.5% - 100% , and the standard average recoveries of Cd in rice reached 93.0% - 100% at room temperature condition, accuracy was lower than 5 %, the method detection limits and quantification limits were 0. 016 μg/L and 0. 048 μg/L respectively, and the pretreatment time can be reduced to 20 min. Compared with the results of the classic method that microwave digestion atomic absorption spectroscopy and microwave digestion ICP - MS, the detection Cd values in various rice had no significance difference （ P 〉 0.05 ）.

关 键 词：稀酸温和提取 直接进样 石墨炉原子吸收法 大米 镉 

分 类 号：TS201.6[轻工技术与工程—食品科学]