同时测定铜、镍、锌的非线性偏最小二乘分光光度法

Simultaneous Determination of Cu, Ni and Znby Non-linear PLS Spectrophotometry

建立了以1_[(5_溴_2_吡啶 )偶氮]_2,7_萘二酚 (5_Br_PADN)为显色剂 ,TritonX_100为增溶增敏剂 ,用非线性偏最小二乘 (NLPLS) -分光光度法同时测定Cu2 +、Ni2 +、Zn2 +的方法。用迭代偏最小二乘法 (IPLS)选择测定波长 ,用自编的MATLAB计算机程序进行处理。结果表明 ,该法不仅克服了三组分之间的相互干扰 ,而且较好地解决了非线性问题。所拟方法用于人工样品的分析 ,准确度较好 。

The optimum conditions of the colour reaction of copper, nickel and zinc with 1 _ [(5 _ bromo _ 2 _ pyridyl) _ azo] _ 2,7 _ dihydroxy _ naphthalene(5 _ Br _ PADN) have been established in the presence of the sensitizer/solubilizer Triton X _100. The proposed method can be applied for the simultaneous spectrophotometric determination of these three elements with the aid of nonlinear partial least square technique(NLPLS). The selection of optimal wavelength was achieved by using the iterative partial least square method(IPLS). An algorithm MATLAB compiled by the authors gave satisfactory results for synthetic samples, indicating that the method not only overcomes interference among the three elements, but also solves the nonlinear problem between absorptivity and concentration.