湿法消解条件对大米中镉定量检测的影响

Effect of wet digestion conditions on the quantitative detection of cadmium in rice

大米中重金属镉(Cd)的定量检测具有重要现实意义。以三种不同镉含量梯度的大米为研究对象,以湿法消解的消解液类型、是否进行赶酸操作和消解时间为研究内容,采用石墨炉原子吸收光谱法对大米中的Cd含量进行测定,确定10 m L HNO_3+10 m L H_2O_2+4滴H_2SO_4对浸泡过夜的1 g样品进行5 h赶酸消解后可准确、快速、简便、相对安全地定量检测大米中的镉。

The quantitative detection of heavy metal cadmium（Cd） in rice has important practicalsignificance. With three kinds of rice with different cadmium concentration gradient as material,three aspects including the type of wet digestion liquid,catching acid or not,and digestion time were researched. The Cd content in rice was determined by graphite furnace atomic absorption spectrometry. The result showed that with 10 m L of nitric acid＋10 m L of sulfuric acid hydrogen peroxide＋4 drops sulfuric acid as wet digestion liquid,quantitative detection of cadmium in rice could be simple,rapid,accurate and relatively safe with 5 h catching acid spectrometry for 1 g sample soaking for one night.