石墨炉原子吸收光谱法测定水生动物中的铬

Determination of Cr in Aquatic Animals by Graphite Furnace Atomic Absorption Spectrometry

采用硝酸和过氧化氢对匀浆过的水生动物进行微波消解,石墨炉原子吸收光谱法测定鱼肉中的铬含量。首先,对微波消解酸体系和微波程序进行了优化,硝酸用量为2.5 mL、过氧化氢用量为2.0 mL,逐步升温到190℃,消解28 min时试剂用量少,消解效果较好;然后用石墨炉原子吸收分光光度仪对几种水生生物中的铬进行测试,方法检出限为0.02 mg/kg,测定结果的相对标准偏差为0.010%~0.056%（n=6）,加标回收率为83%~105%。结果表明：生长期长,生活在水体底部的水生生物中的铬含量相对较高。

Chromium in fish meat was determined by graphite furnace atomic absorption Spectrometry.The aquatic animal samples after being homogenated were digested with HNO3 and H2O2 by microwave digestion method.The acidic systems and microwave digestion procedures were optimized.Best results were obtained when the samples were digested in the mixture of 2.5 mL HNO3 and 2.0 mL H2O2 at 190℃（Note：the digestion temperature should be stepwise increased up to 190℃） for 28 mins.The detection limit for Cr was 0.02 mg/kg.The relatively standard deviations of the data were 0.068%~0.138%（n=6） and the recovery coefficients were 83%~105%.According to this study,it concluded that due to longer growth cycles of the aquatic animals that lived at the bottom of waters,the contents of Cr in the aquatic animals were relatively higher.