【作者】 杨秀双；

【导师】 杨文胜；

【作者基本信息】 北京化工大学 ， 应用化学， 2008， 博士

【摘要】 生物传感器在医学、环境监测、食品及军事等领域有着重要的应用价值,已引起世界各国的极大关注。层状纳米材料具有结构规整、化学组成可调变及可插层组装等特性,而且层状纳米材料剥层后的纳米片具有更开放的结构。本课题基于层状二氧化锰、磷酸锆及其纳米片材料制备新型电化学生物传感器,得到的生物传感器具有良好的稳定性、抗干扰性等,为新型电化学生物传感器的开发提供了新思路,具有广阔的应用前景。1.采用生物相容性材料—磷酸锆纳米片（ZrPNS）固定辣根过氧化酶（HRP）,X-射线衍射（XRD）结果表明ZrPNS在HRP-ZrPNS膜中保持无序结构。傅立叶变换红外光谱（FTIR）结果表明HRP在ZrPNS膜中保持了其基本结构。HRP-ZrPNS修饰玻碳电极（GCE）实现了HRP的直接电化学。以此为基础制备了第三代H₂O₂生物传感器,该传感器对H₂O₂具有较快的响应时间和较宽的线性响应范围。2.利用带相反电荷的肌红蛋白（Mb）和ZrPNS之间的静电吸引作用在固体基质表面交替吸附制备了{Mb/ZrPNS}_n层层白组装电活性薄膜,用电化学交流阻抗谱（EIS）监测和证明了膜的线性生长。场发射扫描电镜（FESEM）结果表明ZrPNS在{Mb/ZrPNS}_n层层自组装薄膜中趋向平行于固体基质表面而使组装薄膜非常平滑。该薄膜修饰GCE在空白底液中出现了一对峰形良好、几乎可逆的Mb亚铁血红素Fe^Ⅲ/Fe^Ⅱ的氧化还原峰,表明Mb在该膜内实现了与GCE表面的直接电子转移。与其它用非导电纳米粒子或聚离子与Mb层层自组装薄膜相比,{Mb/ZrPNS}_n膜具有许多优异的性能,如Mb高的表面覆盖度（Γ^*）,对H₂O₂良好的电催化活性等。3.以阳离子型生物相容性聚合物—阳离子纤维素（QY）为固定化载体固定葡萄糖氧化酶（GOD）,FTIR、紫外-可见光谱（UV-Vis）、圆二色光谱（CD）结果表明GOD在QY膜中保持了它的基本结构。用FESEM对聚合物膜以及酶膜的表面形貌进行了研究。以QY为固定化载体固定GOD制备的第一代葡萄糖生物传感器对葡萄糖响应迅速,并具有较高的灵敏度。以二茂铁为电子媒介体制备了第二代葡萄糖生物传感器,该媒介体型葡萄糖生物传感器表现出良好的抗干扰能力,对葡萄糖的线性响应范围也进一步扩展。QY价格低廉,而且固定化方法简便,因此这种基于QY的生物传感器有望获得实际应用。4.利用生物相容性聚合物QY—二氧化锰纳米片（MNS）纳米复合材料固定HRP,FTIR和CD结果表明HRP在QY-MNS膜中保持了其基本结构。HRP-QY-MNS修饰GCE在空白底液中于-0.272 V（vs.Ag/AgCl）处出现了一对几乎可逆的氧化还原峰,表明HRP在该膜内实现了和电极之间的直接电子转移。与固定HRP的其它材料相比,这种有机-无机纳米复合材料修饰酶电极展示出许多优良的性能:较高的表面覆盖度、较快的响应、对H₂O₂良好的电催化活性以及良好的长期稳定性等。5.用剥离/再组装方法把亚甲基蓝（MB）插入到层状二氧化锰（birnessite简写为Bir）层间制备了超分子插层结构的MB插层二氧化锰（MB-Bir）,用XRD、FTIR及电化学方法对这种材料进行了表征。以MB-Bir作为电子媒介体制备了新型无试剂型H₂O₂电化学生物传感器。循环伏安和安培测试结果表明把MB以这种方式固定后可以稳定有效地在HRP和电极之间传递电子。该生物传感器对H₂O₂具有良好的响应性能,此外该传感器也具有良好的稳定性和抗干扰性。更多还原

【Abstract】 Biosensor possesses important value in physic,environmental monitoring,food and military,and it has caused great concern to all countries in the world.Layered nanomaterials have many specialities, such as orderly structure,adjustable chemical composition, intercalationable,assembliable,and nanosheets obtained from the delamination of layered nanomaterials have a more open structure.Novel electrochemical biosensors have been fabricated based on zirconium phosphate,layered manganese oxide,and nanosheets gained from these layered nanomaterials in this topic.These biosensors possess good stability,anti-interference,and other favorable properties.It provides a new idea to develop new type of electrochemical biosensors,and it has broad application prospects.1.Horseradish peroxidase（HRP）has been immobilized in zirconium phosphate nanosheets（ZrPNS）which are derived via the delamination of layeredα-zirconium phosphate（α-ZrP）.X-ray powder diffraction（XRD） and field emission scanning electron microscopy（FESEM）results revealed that HRP-ZrPNS film remained unorderly structure for the effect of HRP.Fourier transform infrared（FTIR）spectra results revealed that HRP almost remained the basal structure in ZrPNS film.Direct electrochemistry of HRP in ZrPNS film was investigated.Based on these, a third generation reagentless biosensor was constructed for the determination of hydrogen peroxide（H₂O₂）.Rapid response and wide linear range to H₂O₂ has been obtained with this biosensor.2.Alternate adsorption of oppositely charged myoglobin（Mb）and ZrPNS were used to assemble {Mb/ZrPNS}_n layer-by-layer films on solid surfaces by electrostatic interaction between them.Electrochemical impedance spectroscopy（EIS）was used to monitor or confirm the growth of the films.FESEM results indicate that edges of ZrPNS overlap with each other and are faintly recognized,and a smooth film without cracks was formed on the surface of the substrate.The direct electrochemistry of Mb was realized in {Mb/ZrPNS},,films at glassy carbon electrodes（GCE）, showing a pair of well-defined,nearly reversible cyclic voltammetry（CV） peaks for the Mb heme Fe^Ⅲ/Fe^Ⅱredox couple.Compared with other Mb layer-by-layer films with nonconductive nanoparticles or polyions, {Mb/ZrPNS}_n films showed much improved properties,such as higher surface concentration of electroactive Mb（Γ*）,and better electrocatalytic activity toward reduction of H₂O₂. 3.A cationic biocompatible polymer-polyquaternium（QY）has been used to immobilize glucose oxidase（GOD）.FTIR spectrophotometer, circular dichroism（CD）and Ultraviolet-visble（UV-Vis）results indicate that GOD retains its basal structure within the polymer film.The form of the QY film and synthesized composite film have been characterized using FESEM.The first-generation glucose biosensor based on QY exhibits rapid response and good sensitivity.In addition,the characteristics of the second-generation biosensor with ferrocene（Fc）as an electron mediator have also been discussed.The Fc mediated biosensor exhibits a good anti-interference ability,and the extended linear range.Furthermore,QY is inexpensive,and the enzyme immobilization method is very simple, which make the biosensor be promising for practical application.4.A novel biocompatible polyquaternium（QY）-manganese oxide nanosheet（MNS）nanocomposite has been prepared and shown to be a promising matrix for horseradish peroxidase（HRP）immobilization.The resulting HRP-QY-MNS film was characterized by Fourier transform infrared（FTIR）and circular dichroism（CD）spectroscopy,which indicated that HRP retained its native structure in the nanocomposite film. An HRP-QY-MNS film-modified glassy carbon electrode exhibited a pair of well-defined and quasi-reversible cyclic voltammetric peaks centered at -0.272 V（vs.Ag/AgCl）in pH 7.0 phosphate buffer solution.The direct electrochemical behavior of HRP was greatly enhanced in the QY-MNS nanocomposite film compared with that in single-component QY or MNS films.The immobilized HRP showed excellent electrocatalysis in the reduction of hydrogen peroxide（H₂O₂）,which was exploited in the construction of an H₂O₂ biosensor.The biosensor exhibited rapid response and good long-term stability.5.Methylene blue（MB）has been intercalated into layered manganese oxide（birnessite,shortening as Bir）by a delamination/reassembly process and the resulting MB-intercalated bimessite（MB-Bir）material characterized by XRD,FTIR spectroscopy,and electrochemical measurements.A novel reagentless hydrogen peroxide biosensor was fabricated by using the MB-Bir as an electron mediator.Cyclic voltammetry and amperometric measurements demonstrated that MB coimmobilized with HRP displayed good stability and that electrons were efficiently shuttled between HRP and the electrode.The biosensor showed good properties.Moreover,the biosensor exhibited a good stability and anti-interference ability.更多还原