偏最小二乘法—分光光度法同时测定多种食用合成色素

Simultaneous determination of synthetic food colors by method of partial least squares

目的:探讨偏最小二乘法(PLS)分光光度法同时测定多种食用合成色素中的应用。方法:柠檬黄、日落黄、胭脂红、苋菜红的λmax分别是4 2 8±2nm、4 82±2nm、5 0 8±2nm、5 2 0±2nm ,表明它们的吸收光谱严重重叠,用PLS法辅助分光光度法,不经分离,同时测定上述四组分混合体系中各组分的含量。结果:四组分混合体系中各组分的平均回收率和RSD分别为10 0 .6 %、10 0 .5 %、99.5 %、10 1.1%和1.2 8%、1.11%、1.0 1%、1.96 %。实测两种样品,均获得较好结果。结论:PLS法为不经分离直接测定的多组分体系分光光度分析提供了一种新的途径。

Objective:To study the application of partial least squares (PLS) in spectrophotometry,and to simultaneously determine four synthetic food colors with PLS.Methods:λ max for Tartrazine,sunset yellow,ponocean 4R and amaranth were 428±2nm,482±2nm,508±2nm,520±2nm respectively,which revealed significant overlapping of simultaneous determination of mixture of four synthetic food colors by spectrophotometry,whithout any preliminary chemical separation.Results:The mean recoveries and relative standard deviation(RSD) for each sample were 100.6%,100.5%,99.5%,101.1% and 1.28%,1.11%,1.01%,1.96%,respectively.The actual results of two kinds of samples were also satisfactory.Conclusion:The patial least squares may provide a new approach to determination of the content from multi-component spectroscpic data whithout any preliminary chemical separation.