钙调素修饰金电极的交流阻抗行为研究

The AC Impedance Study of Calmodulin Modified on Au Electrode

利用交流阻抗方法,以Fe(CN)63-/Fe(CN)64-氧化还原对为探针,对自组装到金电极表面的钙调素(CaM)膜的成膜过程、不同pH值的影响以及与钙离子的结合情况进行了较系统的研究.实验结果表明,钙调素可以自组装到金电极表面并且其自组装过程较为明显地分为快、慢两个步骤;还发现钙调素膜的性能结构随体系不同的pH值发生有规律的变化,在其等电点,膜的结构最致密;而且钙调素膜与钙离子的结合也分为较明显的三个阶段.

Calmodulin(CaM)as a major intracellular Ca 2+ receptor,was self-assembled on Au e lectrode and investigated by electrochemical im pedance spectroscopy(EIS).The results demonstrated that the s elf-assembly process of CaM could be divided into r apid and slow steps clearly.The influence of pH value on the new modified electrode was found to be re gular,and the most packed structure appeared at the calmodulin's iso-electric-point,the combining process of calmodulin with Ca 2+ was found to be composed of three stag es.In conclusion,our AC impedance study o f CaM is meaningful to reveal the mech anism of CaM in the real life system.