电聚合卟啉衍生物修饰的碘离子选择性电极  

Chemically Modified Electrode Sensitive to Iodide Based on Electropolymerized Porphyrin Derivative

作　　者：袁若[1] 柴雅琴[1] 俞汝勤[1] 

机构地区：[1]湖南大学化学化工系,长沙410082

出　　处：《化学学报》1994年第2期192-198,共7页Acta Chimica Sinica

基　　金：国家自然科学基金;中国科学院长春应用化学研究所电化学开放研究实验室资助课题

摘　　要：用电化学方法将α,β,γ,δ-四(4-氨基苯基)卟啉单体聚合在铂丝电极上,可制备化学修饰型I-选择性电极.质子化卟啉衍生物的立体交联高聚大环与I-的作用具有强的主客体效应,使电极对I-具有高的选择性,并呈现与经典Hofmeister系列及一般金属卟啉中性载体膜电极不同的阴离子选择性次序:I^-》SCN^-》ClO_4^->NO_2^->Br^->NO_3^->Cl^->SO_4^(2-).电极对1×10^(-1)～2.6×10^(-6)mol·dm^(-3)呈线性响应,检测下限8.2×1O^(-7)mol·dm^(-3),斜率61±0.2mV/pl^-(27℃).测试了电极膜的交流阻抗行为.电极具有内阻小、响应快、抗毒化能力强、制备简便等优点.A chemically modified platinum electrode with coated poly[tetra(4-aminophenyl) porphyrin] (PTAPP)was to be used as a new potentiometric iodide selective electrode. The mechanism of the electrode potential response is based on strong host-guest effect between protonized threedimensional cross linked polycyclic PTAPP film and I- ion. The resulting electrode demonstrates a selectivity sequence different from the conventional Hofmeister series and the behavier of ordinary metal porphyrin complexes: I-》SCN-》ClO4 > Br- > NO2- > NO3- > Cl- > SO42-. The response of the electrode is linear in the 10-1 to 2.6×10-6·dm-3I-with a detection limit of 8.2×10-7 mol×dm-3and a slope 61±0.2mV/pI-(n = 5, 27℃). The PTAPP electrode has the advantages of simplicity, low resistance, fast response, fair stability and reproducibility, and resistance to poison. The a. c. impedance spectra of the polymer membrane have also been studided.

关 键 词：卟啉 碘离子 选择电极 膜修饰电极 

分 类 号：O646.54[理学—物理化学]