微波消解样品-石墨炉原子吸收光谱法测定蜂产品中铅、镉、硒
GFAAS Determination of Lead,Cadmium and Selenium in Honey Products with Microwave Assisted Sample Digestion
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摘要: 提出了石墨炉原子吸收光谱法测定4种蜂产品中硒、铅和镉的含量.样品用浓硝酸、过氧化氢浸泡后,加热溶解,补加浓硝酸、过氧化氢进行微波消解.在优化的石墨炉工作条件下,用磷酸二氢铵作基体改进剂测定铅和镉,用PdCl2和Mg(NO3)2作混合基体改进剂测定硒.铅、镉和硒的检出限(3S/N)分别为11.3,1.9,3.7 ng,应用此方法分析了4种蜂产品样品,并用标准加入法作回收试验,测得铅、镉、硒的回收率分别为95.4%~103.8%,89.0%~110.0%,86.8%~96.5%之间,相对标准偏差均小于6%.Abstract: GFAAS with microwave assisted sample digestion was applied to the determination of Pb,Cd and Se in honey products.The sample was first soaked with conc.HNO3 and H2O2,heated to expel oxides of nitrogen,and then digested in a microwave digestor after a supplementary addition of conc.HNO3 and H2O2.Optimum working conditions of the graphite furnace was given and ammonium dihydrogen phosphate was used as matrix modifier in the determination of Pb and Cd,while a mixture of PdCl2 and Mg(NO3)2 was used as matrix modifier in the determination of selenium.Detection limits (3S/N) for Pb,Cd and Se were found to be 11.3,1.9 and 3.7 ng respectively.Samples of honey products were analyzed by the proposed method,and tests for recovery and precision were performed by addition of standards of Pb,Cd and Se to the samples as matrix,giving values of recovery in the ranges of 95.4%-103.8% (for Pb),89.0%-110.0% (for Cd) and 86.8%-96.5% (for Se),with values of RSD′s (n=6) less than 6%.