乙醇脱氢酶在聚苯胺-聚丙烯酸修饰电极上的固定及表征

来源期刊：中南大学学报(自然科学版)2006年第4期

论文作者：周德璧 刘丹平 胡丹 吕新坤

文章页码：714 - 719

关键词：聚苯胺;聚苯烯酸;乙醇脱氢酶;循环伏安法; ADH-PAA-PAn/Pt电极

Key words：polyaniline; polyaerylic acid; alcohol dehydrogenase; cyclic voltammetry; ADH-PAA-PAn/Pt electrode

摘    要：采用循环伏安法在铂电极上于0.5 mol/L苯胺-2.5 mol/L HCl-15%(质量分数)聚丙烯酸的水溶液中制备聚丙烯酸掺杂的聚苯胺膜;并在0.25 mol/L磷酸氢二钠-柠檬酸缓冲溶液(pH=7)中测试掺杂后的聚苯胺膜的电化学性能,聚苯胺-聚丙烯酸(PAn-PAA)复合膜修饰电极在电位为-0.2~0.4 V时出现1对稳定的氧化还原峰,与PAn修饰电极相比,它在此中性缓冲溶液中具有更好的导电性和电化学活性,可用作固定酶的载体和酶催化反应的电子传递媒介。实验中采用两步法将乙醇脱氢酶(ADH)固定至PAn-PAA复合膜中,用循环伏安(CV)、交流阻抗(EIS)和扫描电镜(SEM)等方法对固定乙醇脱氢酶前后膜的性能进行表征。结果表明ADH已固定至复合膜中。

Abstract: Polyaniline-polyacrylic acid (PAn-PAA) composite film was electrochemically deposited on Pt electrode in the solution containing 0.5 mol/L aniline, 2.5 mol/L HCl, 15% poly(acrylic acid) by cyclic voltammetry. And the electrochemical properties of this composite film were tested in 0.25 mol/L disodium hydrogen phosphate-citric acid buffer at pH=7. The resulting PAn-PAA composite film has one stable redox peak in the range of -0.2 -0.4 V, and shows better conductivity and electroactivity in comparison with PAn modified electrode. And it can be used as carrier for enzyme immobilization and mediator for enzyme-catalyzed reaction. Alcohol dehydro-genase (ADH) was immobilized on the PAn-PAA composite film by a two-step method. PAn-PAA composite film and PAn-PAA-ADH film were tested by means of cyclic voltammetry, electrochemical impedance spectroscopy and scanning electron microscopy. The results indicate that ADH is assuredly immobilized on PAA-PAn composite film.

基金信息：湖南省自然科学基金资助项目