Fe(CN)63-/4-和细胞色素c电化学反应温度影响比较  

Temperature Effects on the Electron-Transfer Reactions of Fe(CN)_6^(3-/4-) and Cytochrome c

作　　者：汤儆[1] 杜琳[1] 肖孝建[1] 张宁[1] 

机构地区：[1]福州大学化学化工学院,教育部暨福建省食品安全和分析检测重点实验室,福建福州350108

出　　处：《电化学》2012年第1期43-50,共8页Journal of Electrochemistry

基　　金：国家自然科学基金项目(No.20873112,No.21073038)资助

摘　　要：应用整体升温的方法结合循环伏安和电位阶跃测试研究了温度对Fe(CN)63-/4-体系电化学反应的影响,计算不同温度下Fe(CN)63-和Fe(CN)64-的扩散系数D以及异相反应速率常数k0.实验发现,在Fe(CN)63-/4-体系中,Fe(CN)63-的扩散系数随着温度的升高而增大,而Fe(CN)64-的扩散系数则因受到Fe(CN)63-影响而出现相反的趋势.同时,异相反应速率常数也随温度升高而呈现下降趋势,推测是由于电极表面生成了普鲁士蓝.细胞色素c的核心是血红素铁卟啉环,电子的得失都关联铁原子的氧化还原,与Fe(CN)63-/4-体系的电化学反应在一定程度上有相似性.本文同时应用整体升温的方法研究了温度对细胞色素c电化学反应的影响,计算不同温度下细胞色素c的动力学参数,并与Fe(CN)63-/4-体系比较.Cyclic voltammetric and chronoamperometric techniques were employed to study the temperature effects on the electrochemical reaction of Fe（CN）63-/4- by self-made thermostatic water bath electrochemical cell. The diffusion coefficient D and the formal heterogeneous electron-transfer rate constant k0 were calculated at dif 3- ferent temperatures from 25 ℃ to 75 ℃. In the Fe（CN）63-/4- system, the DO values of Fe （CN）6 were directly proportional to temperature,while Da of Fe（CN）64- inversely proportional to temperature. The values of k0 decreased with the increase of temperature due possibly to the electrode passivation resulted from the decomposition of Fe（CN）63-/4- to a Prussian blue like film. Since the core of Cytochrome c is the heine iron porphyrin, the redox of Cytochrome c reflects that of the iron atoms, which is, in certain degrees, similar to the electrochemical reactions of Fe（CN）63-/4-. system. Accordingly, the same techniques were used to study the temperature effects on Cytochrome c. The kinetic parameters of Cytochrome c at different temperatures were also calculated and compared with those of Fe（CN）63-/4- system.

关 键 词：温度效应 细胞色素C 扩散系数 异相反应速率常数 

分 类 号：Q559.9[生物学—生物化学] O657.1[理学—分析化学]