硫杂大环希夫碱汞(Ⅱ)配合物为中性载体的碘离子选择性电极的研究  

Studies on Iodide-selective Electrodes Based on Thiomacrocyclic Schiff Base Complex of Binuclear Mercury(Ⅱ)as Neutral Carriers

作　　者：罗恩平[1] 柴雅琴[1] 孙爱丽[1] 袁若[1] 

机构地区：[1]西南师范大学化学化工学院重庆市现代分析化学重点实验室

出　　处：《分析测试学报》2005年第6期25-28,共4页Journal of Instrumental Analysis

基　　金：国家自然科学基金资助项目(29705001);教育部优秀青年教师资助计划[教人司(2002)40号];重庆市自然科学基金资助项目(CSTC-2004BB41490)

摘　　要：研究了以新型硫杂大环希夫碱金属Cu(Ⅱ)、Hg(Ⅱ)、Ni(Ⅱ)配合物为中性载体的电位型阴离子选择性电极,结果表明,该硫杂大环希夫碱的Hg(Ⅱ)配合物作为载体的电极对Ⅰ-具有良好的电位响应特性,且呈现反Hofmeister行为,其选择性序列为Ⅰ-＞Sal-＞ClO4-＞SCN-＞NO3-＞NO2-＞F-＞Br-＞SO32-＞SO42-＞H2PO4.在pH2.5的磷酸盐缓冲体系中该电极具有最佳的电位响应,在0.1～1.0×10-6mol/L范围内呈近能斯特响应,斜率为-57 mV/pI-(25℃),检出限为8.9×10-7mol/L,用交流阻抗及紫外可见光谱技术研究了电极的响应机理,并将电极用于药品分析,结果满意.In this paper, a new thiomacrocyclic Schiff base complex of binuclear mercury（Ⅱ） as neutral carrier is used for preparing an iodide-selective membrane electrode, which exhibits a preferential potentiometric response to iodide and an anti-Hofmeister selectivity pattern in following order： Ⅰ^-〉Sal^-〉ClO4^-〉SCN^-〉 NO3^-〉NO2^-〉 F^-〉Br^-〉SO3^2-〉SO4^2-〉H2PO4^-. The resulting electrode displays a near-Nernstian potentiometric response for 0.1-1.0 × 10^-6 mol/L iodide with a detection limit of 8.9 ×10^-7 mol/L and a slope of - 57 mV/pI^- in phosphate buffer solutions of pH 2.5 at 25℃. Moreover, the response mechanism of the electrode was discussed with the a.c. impedence and spectroscopic techniques. The electrode can be applied to determination of iodide in drug with satisfactory results.

关 键 词：硫杂大环希夫碱合汞(Ⅱ) 中性载体 碘离子 离子选择性电极 

分 类 号：O657.15[理学—分析化学] O613.44[理学—化学]