【作者】 陈宏；

【导师】 旷亚非；

【作者基本信息】 湖南大学 ， 材料学， 2004， 硕士

【摘要】 本文分别以聚间苯二胺膜（PMPD）、聚苯胺-石墨复合膜（PGPCF）和Pt修饰纳米纤维聚苯胺膜[Pt／（Nano-fibrous PANI）]为基质，首次采用脉冲电流聚合法分别制得聚间苯二胺葡萄糖氧化酶电极（PMPD-GOD）和Pt修饰纳米纤维聚苯胺葡萄糖氧化酶电极[PMPD-GOD／Pt／（Nano-fibrous PANI）]，或采用电化学掺杂法制得聚苯胺-石墨葡萄糖氧化酶电极（PGPCF-GOD）。论文采用扫描电子显微镜（SEM）及电化学方法对以上聚合物膜层的微观结构和酶电极的电化学响应性能进行了详细的研究讨论。研究结果表明，酶电极的电化学响应性能与聚合物膜层结构密切相关，PMPD膜和PGPCF膜呈现网状多孔结构，膜层具有较大的比表面，有利于酶的固定和离子的迁移；Pt／（Nano-fibrous PANI）膜层结构为直径50～80nm的Pt微粒均匀分布于直径约100nm的聚苯胺纤维上，膜层不但具有非常大的比表面，而且均匀分散在聚苯胺纤维表面的Pt颗粒对H₂O₂氧化具有很好的电催化活性。论文还系统讨论了电化学制备参数对聚合物膜层结构的影响以及电化学检测温度、检测电位以及葡萄糖溶液的pH值对上述葡萄糖氧化酶电极生物电化学响应特性的影响。当脉冲通断比为1：1，脉冲频率为10Hz，平均电流密度为1mA／cm²，葡萄糖氧化酶浓度为5g／L时，聚间苯二胺具有较好的多孔网络结构。电化学研究结果表明，各酶电极均具有较好的生物电化学响应特性，其中以PMPD-GOD／Pt／（Nano-fibrous PANI）电极响应性能最为优异，论文通过研究Pt颗粒沉积方法及参数、Pt载量、纳米纤维PANI膜层厚度对Pt／（Nano-fibrous PANI）电极电催化氧化H₂O₂的影响，并且将具有优良催化性能的Pt／（Nano-fibrousPANI）电极用于制备葡萄糖氧化酶电极。结果显示该酶电极2×10^-6～12×10^-3mol／L范围内对β-D葡萄糖具有较好的线性响应性能，响应时间约为7s，且对尿酸和抗坏血酸都具有很好的抗干扰性能。同时，PMPD-GOD／Pt／（Nano-fibrous PANI）电极在人体血清中的研究结果表明，该酶电极对人体血清中葡萄糖浓度的测量值与医院仪器分析的结果偏差很小，从而证明其具有一定的应用价值。 论文通过计算酶催化反应的有关动力学参数，得到PMPD-GOD、PGPCF-GOD及PMPD-GOD／Pt／（Nano-fibrous PANI）酶电极的最大响应电流密度i_m分别为231.4μA／cm²、357.17μA／cm²和917.4μA／cm²，相应的米氏常数K′_m分别为15.33×10^-3mol／L、16.57×10^-3mol／L和9.34×10^-3mol／L。更多还原

【Abstract】 Glucose biosensors were prepared by one-step electrochemical method or electrochemical doping method with poly (m-phenylenediamine) film (PMPD), polyaniline-graphite powder composite film (PGPCF) and Pt-dispersed nano-fibrous PANI film [(Pt/(Nano-fibrous PANI)). The morphology of polymer films and the electrochemical response performance were investigated by scanning electron microscopy (SEM) and electrochemical method. The results show that the morphology of PMPD and PGPCF are porous and netty structure, which possess large specific area and benefit to the immobilization of glucose oxidase (GOD). And PANI films with nano-fibrous structure and Pt microparticles with 50-80 nm diameter dispersed on PANI nano-fiber can be observed from the morphology of Pt/(Nano-fibrous PANI), which has very large specific surface area to the immobilization of GOD and good electrocatalytic activity to the electrooxidation of H202-Furthermore, the influence of electrochemical preparation parameters on the morphology of polymer and the effect of polymer morphology, detecting temperature, potential and pH value of glucose solution on the performance of electrochemical response of enzyme electrode are studied in detail. In order to obtained the optimal porous and netty PMPD film with excellent electrochemical response properties, the synthetic parameters should be controlled at the following conditions: ton/toff, 1:1; pulse frequency, 10Hz; mean current density of PGM,1mA/cm2; GOD concentration, 5g/L.The enzyme electrodes prepared above all show good electrochemical response performance, and the Pt/(Nano-fibrous PANI) enzyme electrode shows the best response performance compared to the other two enzyme electrodes. The effects of conditions for Pt deposition by PGM, Pt loading and PANI thickness on the electrocatalytic activity of Pt/(Nano-fibrous PANI) for H2O2 oxidation have also been researched. And the Pt/(Nano-fibrous PANI) with the optimal electrocatalytic properties for H2O2 oxidation was then used to construct the PMPD-GOD/Pt/ (Nano-fibrous PANI) electrode. The results show the PMPD-GOD/ Pt/(Nano-fibrous PANI) electrode gave a linear response to glucose in the range 2xlO-6 to 12xlO-3 mol/L, the corresponding linearity (R) is more than 0.99. And a fast amperometricresponse time of about 7s (95% of steady-state current) to glucose and good anti-interferent to uric acid or ascorbic acid have also been observed. Furthermore, the PMPD-GOD/Pt/(Nano-fibrous PANI) electrode was applied to determination glucose concentration in serum, and the analytical results provided by the hospital and those determined by using the enzyme electrode agrees closely.Based on the calculating of the kinetic parameters, the maximum response current density ( im ) of the PMPD-GOD, PGPCF-GOD and PMPD-GOD/Pt/ (Nano-fibrous PANI) electrode were 231.4uA/cm\ 357.17uA/cm2 and 917.4uA/cm2, respectively, and the corresponding Michaelis-Menten constant ( K’m ) were 15.33 l(r3mol/L, 16.57 10-3mol/L and 9.34 10-3mol/L, respectively.更多还原