食用油中铜铅锌溶出伏安同时测定的主成分分析模型

食用油中重金属含量是一项重要的安全检测指标。以铜、铅、锌为检测对象,首先用差分脉冲溶出伏安法对三种金属混合溶液进行检测;然后对检测信号进行平滑及平滑求导处理,以降低信号噪声;最后用主成分回归构建食用油中基于两种信号降噪方法的铜、铅、锌不经分离的同时检测模型。预测集浓度预报结果可知,基于信号平滑求导的主成分回归测试模型检测结果较好。通过实际样品检测,并与原子吸收光谱法检测结果对比,该模型的预报结果令人满意。因此,认为该方法是一种适宜食用油生产企业、质检部门进行铜、铅、锌常规检测的有效方法,应用前景较好。

Principal Component Analysis Models for Simultaneous Determination of Copper Lead and Zinc in Edible Oils Using the Stripping Voltammetry Method

The content of heavy metals in edible oils is an important safety indexes.Firstly,the contents of Cu,Pb and Zn were detected in solutions of their different concentrations by differential pulse stripping voltammetry;then the stripping signal was dealt with smoothing and smoothing-derivation so as to reduce the signal-to-noise ratio;finally,regression test models of Cu,Zn and Pb corresponding to the two denoising methods were respectively established by principal component regression without any chemical decomposition.Comparing their prediction values of forecasting samples,the regression model based on smoothing-derivation has a better result.The tests of practical samples show that the forecast results of the model are quite satisfactory than that of flame atomic absorption spectrophotometer.Therefore,the method based on smoothing-derivation regression model for routine determination of Cu,Pb and Zn in edible oil producing enterprises and quality inspection department is effective and has a better prospect.