碳纳米管及石墨烯在电化学生物传感器中的应用

发布时间：2018-04-03 19:15

  本文选题：碳纳米管　切入点：石墨烯　出处：《天津理工大学》2017年硕士论文

【摘要】：碳纳米管和石墨烯都是新型碳纳米材料,均由sp~2杂化的碳原子构成,都具有纳米材料独特的性质,如比表面积大、高的导电性、高的化学稳定性、良好的生物相容性及电催化活性等,使得它们可以应用于电化学生物传感器领域。本文制备了适用于电化学生物传感器的两种电极材料,分别为金/二氧化钛/碳纳米管及金/石墨烯管复合材料,并分别构造了同步检测5种生物物质的电化学传感器。采用紫外光催化法把金离子原位还原成金纳米粒子获得了金/二氧化钛/碳纳米管复合材料,并采用脉冲电沉积法把该纳米复合物修饰到玻碳电极上制备了金/二氧化钛/碳纳米管修饰传感电极。由于金纳米粒子、二氧化钛纳米粒子及碳纳米管复合形成了三维的网状结构,且在三者的协同电催化增效作用下,成功检测到了抗坏血酸(AA)、多巴胺(DA)、尿酸(UA)、色氨酸(Trp)和亚硝酸根(NO_2-)这5种分析物,而同时测定它们时的线性浓度范围分别为3-281μM、0.3-15μM、1-162μM、1-162μM和4-225μM,检测限分别为1μM、0.2μM、0.6μM、0.8μM和3μM。该复合材料的特点是选择性好,且适合涂覆于各种导电基底上制备低成本、实用的无酶传感试纸。采用热丝化学气相沉积法制备了自支撑石墨烯管后,再以多电势阶跃法把金纳米粒子沉积在自支撑石墨烯管上,制备了金/石墨烯管复合电极。因金纳米粒子具有高生物相容性及电子捕获能力,而石墨烯具有大的电子迁移率及电催化活性位点,可以同步检测到AA、DA、UA、鸟嘌呤(GUA)和腺嘌呤(ADE)。该传感电极检测上述5种生物物质时,DA和AA、UA和DA、GUA和UA、ADE和GUA的峰电位差分别达到了208mV、140 mV、360 mV、264 mV,检测AA、DA、UA、GUA和ADE的线性浓度范围分别为4-600μM、0.4-20μM、0.6-40μM、6-500μM、0.6-40μM,检测限分别为0.9μM、0.38μM、0.75μM、12.75μM和0.5μM。该复合电极的特点是选择性好、检测限低以及非常稳定,且不必使用固体基础电极,因此使用寿命长。
[Abstract]:Carbon nanotubes (CNTs) and graphene (graphene) are new carbon nanomaterials, both of which are composed of sp~2 hybrid carbon atoms. Both of them have unique properties such as large specific surface area, high conductivity and high chemical stability.Because of their good biocompatibility and electrocatalytic activity, they can be used in electrochemical biosensors.In this paper, two kinds of electrode materials suitable for electrochemical biosensor, namely gold / titanium dioxide / carbon nanotube and gold / graphene tube composite, were prepared, and electrochemical sensors for simultaneous detection of five kinds of biomaterials were constructed.Gold / titanium dioxide / carbon nanotube composites were prepared by in situ reduction of gold ions into gold nanoparticles by ultraviolet photocatalysis.The gold / titanium dioxide / carbon nanotube modified sensing electrode was prepared by pulsed electrodeposition.Because of the gold nanoparticles, titanium dioxide nanoparticles and carbon nanotubes formed a three-dimensional network structure, and under the synergistic effect of the three electrocatalysis,鎴愬姛妫，

本文编号：1706547