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氧化还原蛋白质和酶等生物大分子的直接电化学研究是生物电化学界和生物学界非常关注的热点问题。它的研究对于人们获得蛋白质和酶的热力学和动力学性质，深入认识蛋白质和酶等生物大分子在生命体内的生理作用以及开发新型生物传感器、新型生物燃料电池等生物电子器件具有重要的理论和应用指导意义。从某种意义上讲，研究生命过程，实质上就是研究生物体中的电子传递过程。因此，用电化学方法来研究蛋白质的电子传递过程有着特别的优越性。本论文主要以新型纳米材料为生物载体，构筑生物分子／纳米材料的界面，实现氧化还原蛋白质和酶等生物大分子的直接电子传递并获得优良的生物电催化性能。全文共分四个部分：第一章绪论本章主要综述了氧化还原蛋白质的电化学意义和研究进展，简要介绍了纳米材料的特性，制备等，着重介绍了纳米材料修饰电极在生物电化学中的应用。第二章细胞色素c在无机复合纳米材料修饰电极上的直接电化学研究采用超声辅助湿法制备了羟基磷灰石与碳纳米管（HAp／MWNT）无机复合纳米材料，并将其修饰到玻碳电极表面，实现了细胞色素c（Cyt c）的电化学研究。实验结果表明，复合材料对细胞色素c有很好的催化作用，其氧化还原峰峰差（△Ep）为78 mV，式电位为15 mV。在6.0×10-7～5.0×10-5 mol／L浓度范围内，Cyt c的峰电流与其浓度呈良好的线性关系，其检测下限为3.0×10-7mol／L。第三章氧化还原蛋白质在凹凸棒土修饰电极上的直接电子转移通过超声搅拌对凹凸棒土进行纯化，首次将凹凸棒土应用于氧化还原蛋白质的固定及其生物电化学研究。通过XRD和TEM表征了凹凸棒土的结构和形态，UV-Vis、FT-IR表明凹凸棒土具有良好的生物兼容性和较高的稳定性，能快速促进蛋白质的直接电子转移，细胞色素c和血红蛋白在凹凸棒土修饰电极上都有良好的电化学响应，该电极对过氧化氢有良好的催化作用，为第三代生物传感器的开发提供思路。第四章细胞色素c在马铃薯膳食纤维修饰电极上的直接电化学行为研究用水蒸汽爆破和氧化法对马铃薯废渣进行处理制备马铃薯膳食纤维（PDF），并用FT-IR、SEM等方法进行表征。结果表明，马铃薯渣中的半乳聚糖在蒸汽爆破下由长链断成短链，且由原来的块状变成片状、无规则的空间网层结构，断链的半乳糖醛基在氧化作用下生成羧基；所得到的PDF具有比表面积大、吸附位点多等特点。将马铃薯膳食纤维与聚乙烯醇（PVA）制备成水凝胶修饰到玻碳电极表面，研究细胞色素c（Cyt c）在该电极上的直接电化学，探讨了马铃薯膳食纤维与Cyt c间的相互作用，构建了新型过氧化氢生物传感器。用计时电流法测Biomacromolecule including proteins and enzymes are the primary groups of life. Directelectrochemistry of proteins and enzymes has aroused great interest in biological andbioelectrochemical field. Studies on direct electrochemistry of redox proteins/enzymes can be used togain their thermodynamics and the kinetic property, understand the mechanistic of electron exchangeamong proteins in biological systems and physiological action. Moreover, direct electron transferbetween immobilized enzyme and underlying electrode can establish a foundation for fabricating newkinds of mediator-free biosensor, biofuel cell and bioreactors. In a sense, the essence of studying lifeprocess is to study the electron transfer process. Therefore, uses electrochemistry method to study theelectron transfer process of proteins have the special superiority.The present paper mainly take the new nanomaterials as the biological carrier and the molecularwire to construct a biological member/nanomaterials on the nanometer contact surface, thenanostructured materials can promote the electron transfer of redox proteins and enzymes. The fulltext divides four parts:1. IntroductionThis chapter content mainly summarized the significance on the electrochemistry of redoxproteins and their research progresses, introduced briefly the nanomaterials characteristic, thepreparation and so on, emphatically introduced the nanomaterials modified electrode in biologicalelectrochemistry application.2. Direct electrochemistry of cytochrome c at nanocomposite modified electrodeHydroxyapatite/carbon nanotube composite materials was synthesized with the help ofultrasonic agitation and modified on the surface of glass carbon electrode. The electrochemicalbehaviors of cytochrome c on this modified electrode were studied. The results showed thatcytochrome c exhibited good current responses with the linear ranging from 6.0×10-7 to 5.0×10-5mol/L, the calculated detection limits was 3.0×10-7 mol/L at S/N=3.3. Direct electron transfer of redox proteins at attapulgite modified electrodeNatural nano-structure attapulgite clay was purified by mechanical stir with the aid of ultrasonic