肌红蛋白-壳聚糖-金胶纳米复合薄膜修饰电极的电化学性质

在pH=5.4的HAc-NaAc缓冲溶液中, 肌红蛋白-壳聚糖-金胶薄膜修饰电极在-0.20 V(vs. Ag/AgCl) 处有一对准可逆的氧化还原峰, 为Mb血红素辅基Fe(Ⅲ)/Fe（Ⅱ）电对的特征峰. 在壳聚糖 金胶纳米复合薄膜的微环境中， 肌红蛋白与玻碳电极之间的电子传递明显加快. 考察了扫速、 溶液pH值及支持电解质浓度等因素对肌红蛋白电子传递的影响. 紫 外光谱结果表明， 肌红蛋白在壳聚糖 金胶溶液中依然保持其原始构象， 该肌红蛋白-壳聚糖-金胶纳米复合薄膜修饰电极还可用于溶解氧的催化还原.

Electrochemical Property of Myoglobin-chitosan-colloid Gold Film Modified Glass Carbon Electrode

Myoglobin(Mb)-chitosan-colloidal gold films were made by casting a solution of Mb, chitosan and colloidal gold on glass carbon electrodes. Mb incorporated in chitosan colloidal gold films gave a pair of stable, well defined, and quasi reversible cyclic voltammetric peaks at about -0.20 V(vs.Ag/AgCl) in 0.1 mol/L NaAc HAc buffer (pH=5.4), being the characteristic peaks of the Mb heme Fe(Ⅱ)/Fe(Ⅲ) redox couple. The effects of scan rate, pH and concentration of buffer solutions on the electrochemical behavior of Mb were studied in detail. Position of the Soret absorbance band suggests that Mb in chitosan colloidalgold kept its secondary structure similar to the native states. Oxygen was cata lytically reduced by Mb in chitosan colloidal gold films.