【作者】 张波；

【导师】 艾仕云； 曲祥金；

【作者基本信息】 山东农业大学 ， 应用化学， 2007， 硕士

【摘要】 纳米粒子由于其独特的光学、电学、催化等性质,在修饰电极上的应用研究已引起人们极大的关注。本文将纳米技术同电化学方法结合,以纳米金/丝素复合材料修饰电极,制备了多种电化学生物传感器,研究了蛋白质和酶的直接电化学响应,并以环境污染物对苯二酚、过氧化氢为对象对制备的传感器的应用进行了研究。首先以丝素原位还原氯金酸合成了纳米金/丝素复合溶胶,对其光谱性质进行了表征。实验表明制得的纳米金粒子包埋在丝素胶体中,引起了丝素的荧光和共振光散射的增强。制得的复合溶胶具有很好的分散性和稳定性,可长期保存。其次,探讨了纳米金/丝素复合膜修饰电极的制备和应用。以纳米金/丝素复合材料修饰金电极,制备出对对苯二酚具有电催化作用的电化学传感器。实验证明丝素纳米金修饰电极可用于废水样中对苯二酚的测定,应用结果令人满意。第三,探讨了纳米金/丝素修饰电极对生物大分子的直接电化学作用。以纳米金/丝素复合膜固定细胞色素C修饰玻碳电极,制备了对细胞色素C具有电催化氧化作用的电化学生物传感器。表明纳米金/丝素复合膜对细胞色素c具有直接电化学作用。第四,以纳米金/丝素复合膜固定辣根过氧化物酶(HRP)修饰玻碳电极的生物传感器,实现了对H2O2的测定。实验结果表明,HRP在纳米金/丝素复合膜表面能进行有效的直接电子转移反应。对H2O2的还原具有很好的电催化活性,能快速地响应H2O2浓度的变化。本文制备的丝素纳米金修饰电极及固定酶的生物传感器,具有方法简单、易于操作的优点,可用于生物氧化还原蛋白质和酶的直接电子转移及生物燃料电池,也可实现对生物及环境痕量物质的检测,具有广阔的应用前景。更多还原

【Abstract】 Due to the unique character of nanoparticles such as optical, electrical and catalytic character, nanoparticles have attracted much attention of many chemists for their novel application in modified electrode. In this paper, nanoparticles modified electrode has been fabricated by combining nanotechnique with electrochemical method. Besides, nanoparticles modified electrode fabricated by us is taken into the study on environmental pollution. Such as p-benzenediol and H₂O₂.First,we prepared gold nano-particles colloidal sol by the reduction of HAuCl4 with silk fibroin, and took the colloidal sol into the preparation and optics research..Nano-Au/silk-fibroin colloids were prepared by situ reduction HAuCl4 with silk-fibroin. UV-Vis absorption, fluorescence spectra and resonance scattering spectra have been used to study the structure and characterization of the nanocolloids. It was showed that the Au nanoparticles were uniformly embedded in silk-fibroin colloid, which resulted in enhancement of the strength of fluorescence spectra and resonance scattering spectra of silk-febroin.The prepared colloids owed good dispersity and stability,so it can be kept for a long period.Second,gold electrode modified with gold nano-particles was employed for electrocatalytic oxidation of p-benzenediol.Several factors affected the electrocatalytic oxidation were investigated,such as acidity and scan rate.The modified electrode has good electrocatalysis to p-benzenediol in acid.In 0.25mol/L phosphate buffer solution（pH=3.55）,when differential pulse voltammetric method was used,there was an exerllent linearity between oxidation current and concentration of p-benzenediol in the range of 4×10- 6～1×10-3 mol/L with a detection limit of 1.5×10-7mol/L.The results revealed that the modified electrode could be used to the determination of p-benzenediol in imitative waste water samples with good result.Third,the modified electrode with gold nano-particles/@silk-fibroin immobilized on glassy carbon electrode was employed for electrocatalytic oxidation of cytochrome c. The affection of acidity and scan rate were investigated, and the electrocatalytic oxidation mechanism of cytochrome c at modified electrode was studied. The results show that gold nano -particles immobiled silk further the direct electron transfer of cytochrome c.Fourth,horseradish peroxidase and gold nano-particles was immobilized on the surface of the glassy carbon electrode can undergoing effective Direct Electrochemistry. The results show that gold nano-particles/silk fibroin immobiled further the direct electron transfer of Horseradish Peroxidase .The result also showed that the immobiled HRP retained its bioelectrocatalytic activity for the reduction of H2O2 and can quickly respond to the change of the concentration of H₂O₂.The mothod of the preparation of biosensor in this text can easily be manipulated,it can be used to acquire the direct electrochemistry of other enzymes or protein and bio-fuel cells,and it can also be used to determine environmental trace pollution.So it probablys owe a good application in the future.更多还原