新型高选择性水杨酸根离子电极的研究

Highly Selective Salicylate Electrode Based on New Complexes of Cobalt(Ⅱ)-as Neutral Carriers

报道了基于乙酰丙酮缩二亚丙基三胺合钴（Ⅱ）（Co（Ⅱ）-BAEDDPA）为载体的溶剂聚合膜阴离子敏感电极，该电极对水杨酸根离子（Sal^-）具有高的电位选择性和灵敏度，且呈现反Hofmeister选择性行为，其选择性序列为Sal^-〉ClO4^-〉SCN^-〉I^-〉Br^-〉NO2^-〉NO3^-〉SO3^2-〉Cl^-〉SO4^2-。该电极电位对水杨酸根离子呈近能斯特响应，其线性范围为2．0×10^-6～1．0×10^-1moL／L Sal^-；斜率为-68．8mV／dec；检出限为6．0×10^-7moL／L Sal^-。采用交流阻抗和光谱分析技术研究了电极的响应机理，并将电极用于药品分析，结果令人满意。

In this study, anion-selective electrode based on bisacetylacetone-ethylene -diaminodipropylammecobalt（Ⅱ ） metallic complex （Co（Ⅱ ）-BAEDDPA） as the neutral carrier is reported. The electrode exhibits unique selectivity and high sensitivity toward salicylate ion, which displays an anti-Hofmeister selectivity pattern. The Selectivity sequence observed is Sal^- 〉 CIO4^- 〉 SCN ^- 〉 I^ - 〉 Br^- 〉 NO2^- 〉 NO3^- 〉 SO3^2- 〉 Cl^- 〉 SO4^2-. The electrode gives linear response over the concentration range of 2.0 ×10^ -6 - 0.1 mol/L Sal^- with a defection limit of 6.0 ×10^ -7 mol/L Sal^- and a slope of - 66.8 mV/dec. In buffer solutions of pH 4.0. The response mechanism is discussed in view of ac impedance technique and ultraviolet （UV） spectroscopy technique. The electrode can be applied to medicine analysis and the result is fair agreement with the result obtained by precipitation method.