关键词: 温度效应, 细胞色素c, 扩散系数, 异相反应速率常数

Abstract: 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 different temperatures from 25 °C to 75 °C. In the Fe(CN)63-/4- system, the DO values of Fe(CN)63- were directly proportional to temperature, while DR 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 heme 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 temperature were also calculated and compared with those of Fe(CN)63-/4- system.

Key words: Temperature effect, Cytochrome c, Diffusion coefficients, formal heterogeneous electron-transfer rate constant