四种稻米中镉检测方法比较研究

Comparative study of four methods for determination of cadmium in rice

采用石墨炉原子吸收法、固体直接进样电热蒸发原子吸收光谱法、电化学阳极溶出伏安法和X射线荧光光谱法测定稻米中镉含量,对4种定量检测方法的准确度、精密度以及相对误差进行了比较分析。研究结果表明,固体直接进样电热蒸发原子吸收光谱法操作简单,无需化学前处理,单样检测时间在3 min左右,快速高效,精密度良好,可信度高。通过4种检测方法对比,固体直接进样电热蒸发原子吸收光谱法的测试结果准确度高,与国家标准方法相比相对误差多数在±10%以内,重复6次测定的RSD为3.9%,可作为一种新型快速检测稻米中镉的方法,具备方便快速、准确度高、重复性好等优点,在基层可广泛应用。

The cadmium content in rice was determined by graphite furnace atomic absorption spectrometry,solid direct injection electrothermal evaporation atomic absorption spectrometry,electrochemical anodic stripping voltammetry and X-ray fluorescence spectrometry.The accuracy,precision and relative error of the four quantitative detection methods were compared and analyzed.The results show that in the rapid detection method,the solid direct injection electrothermal evaporation atomic absorption spectrometry is simple to operate,without chemical pretreatmnt,and the single sample detection time is about 3 minutes.It is fast and efficient,with good precision and high reliability.Compared with the four detection methods,the test results of solid direct sampling electrothermal evaporation atomic absorption spectrometry have high accuracy,and the relative error is mostly within±10%compared with the national standard method,and the RSD of 6 repeated measurements is 3.9%.As a new method for rapid detection of cadmium in rice,it has the advantages of convenience,rapidity,high accuracy and good repeatability,and can be widely used in grassroots.