【作者】 阳明辉；

【导师】 沈国励； 俞汝勤；

【作者基本信息】 湖南大学 ， 分析化学， 2007， 博士

【摘要】 生物传感器在医疗、医药、生物工程、环境保护、食品等领域具有广泛的应用前景,因而吸引了众多研究者的兴趣。近年来作为危害人类健康的主要疾病之一的糖尿病,患病率与日俱增,是仅次于心血管病、癌症的第三大危险性疾病。葡萄糖生物传感器可以高效、简便、快速的测定病人的血糖浓度,因此得到临床广泛应用。但传统葡萄糖传感器存在灵敏度较低,响应速度慢以及稳定性较差等缺点。近年来,纳米材料得到广泛研究与应用,将纳米材料应用于生物传感器的制备可以较大提高传感器的响应性能。本文利用纳米材料优良的物理、化学、电催化性能以及它们良好的生物相容性制备了多种不同形貌的纳米材料,将这些纳米材料组装到电极表面所得修饰电极可在低电位下实现对过氧化氢的灵敏检测,能用于生物传感界面的构建。将葡萄糖氧化酶、胆固醇氧化酶等氧化酶采用多种方法固定到界面上,制备的生物传感器具有较高的灵敏度、较低的检测下限以及快的响应速度。具体内容如下:(1)采用模板法合成纳米管、纳米线阵列。纳米结构大的表面积能极大的提高酶的负载量,同时为固定酶提供了很好的微环境。将垂直排列的纳米线或纳米管阵列作为传感器件能保证酶和底物之间有尽可能大的接触面积,提高生物传感器的响应性能。首先将聚碳酸酯模板固定在电极上,用电沉积法制备了金纳米线阵列。利用纳米线阵列有效的表面积和金对生物分子的生物相容性,我们选取血红蛋白研究了金纳米线阵列对蛋白质的固定以及蛋白质的直接电化学。紫外和红外光谱表明血红蛋白分子吸附到纳米线表面并没有明显失活现象。循环伏安图中血红蛋白修饰的纳米线阵列有一对可逆的氧化还原峰,表明实现了直接电化学。实验发现参与直接电化学的蛋白质的量随着纳米线长度的增大而增加。结合循环伏安法和石英晶体微天平,计算出当纳米线长度为2μm时,70%的吸附到纳米线表面的蛋白质参与了直接电子转移(第2章)。利用相类似的方法制备了铂纳米线阵列,研究了铂纳米线阵列对过氧化氢的催化性能。在0V电位下,阵列对过氧化氢有较大响应,灵敏度比普通铂电极大了50倍,并有较宽的线性范围。低的检测下限是由于纳米线阵列能提高性噪比,高的检测上限归因于阵列较大的表面积提供了大量的催化活性位点。将葡萄糖氧化酶吸附到纳米线阵列上,得到的葡萄糖传感器有较大的灵敏度,较宽的线性范围,可实现对葡萄糖的无干扰检测(第3章)。我们用氧化铝模板合成了组氨酸/铁氰化镍纳米管阵列。组氨酸的引入促使了纳米管阵列的形成,而不是单个分散的纳米管,同时在纳米管形成的过程中,纳米管壁由于吸附了组氨酸而修饰了大量的氨基。研究了纳米管阵列修饰玻碳电极更多还原

【Abstract】 There has been considerable interest in studying biosensors because they have potential applications in medical treatment, medicine, bioengineering, environmental protection and food industry. Recently, diabetes, as one of the main diseases that threaten human health, suffers more and more people, and is the third dangerous disease following cardiology and cancer. Glucose biosensors can be used to determine concentration of glucose in the blood conveniently and with high efficiency, so that have widely used clinically. But the conventional glucose biosensors have many problems such as low sensitivity, slow response and poor stability. In the past few years, nanomaterials have been widely researched and used. Applying nanomaterials for the fabrication of biosensors will greatly improve the performance of the resulting biosensor. This research prepared many nanomaterials with different morphology, taking advantage of the good physical, chemical, electrocatalytic and biocompatibility of these nanomaterials and using them for the preparation of sensors. The modified sensors can be used to determine hydrogen peroxide in low potential with high sensitivity, ideal for the construction of biosening platform. Immobilizing oxidases such as glucose oxidase and cholesterol oxidases onto the platform with different method, the resulting biosensors have high sensitivity, low detection limit and fast response time. The details are summarized as follows:(1) Prepared nanowire and nanotube array using template method. The large surface area of these nanostructures can increase the amount of enzymes immobilized, at the same time provide a friendly microenvironment for enzyme loading. It would be a significant advancement if perpendicularly aligned nanowire and nanotube array could be formed as sensing materials. The well defined surface area facilitated enzyme-substrate contact, greatly improving the performance of the resulting biosensor. First, gold nanowire array can be grown by electrodeposition in polycarbonate membrane directly immobilized on glassy carbon electrode surface. Taking advantages of the well defined surface area of the nanowire array and biocompatibility of metal gold toward biomolecules, we selected hemoglobin and investigated the efficiency of protein immobilization on gold nanowire array and the direct electrochemistry of hemoglobin. Uv-visible and FT-IR spectroscopy indicated on obvious denaturation of the proteins was observed after adsorption onto the更多还原