【作者】 赵文琪；

【导师】 黄俊；

【作者基本信息】 武汉理工大学 ， 材料学， 2010， 硕士

【摘要】 光纤传感技术是材料、信息、生命、化学、物理等多学科交叉的研究领域,其中光学敏感材料研究对于光纤传感技术的发展起着决定性的影响。高性能光纤生物传感材料的制备是研制高性能光纤生物传感器的关键技术之一,而光纤生物传感敏感材料必须具备对待测物质优异的敏感性能、高度的选择性、较快的响应速度和较长的使用寿命等特点。对葡萄糖的检测在临床诊断(特别是糖尿病)、基础医学研究及食品工业等领域中十分重要,目前采用的检测方法主要有仪器分析和电化学传感器,存在检测过程复杂、响应慢、成本高等缺点。光纤葡萄糖传感器具有检测精度高、响应快、操作简单、成本低等优点,是检测葡萄糖的有效手段,其研究具有重要的意义。本文制备了二氧化硅(Si02)纳米粒子并在其表面引入氨基,用来固定葡萄糖氧化酶,并将固定化酶与荧光指示剂复合,制备出同时具有催化及光敏特性的纳米复合生物传感材料。设计和构建了基于酶催化及荧光猝灭的光纤葡萄糖传感器,并初步研究了传感器性能。本论文的主要工作分为以下几个方面：(1)采用Stober水解法制备粒径均一大小为100nm左右的SiO2纳米粒子,并通过扫描电镜对其形貌进行表征。利用硅烷化试剂3-氨基丙基三已氧硅烷(APTES)及偶联剂戊二醛(GA)对SiO2纳米粒子表面进行改性,引入氨基,以固定葡萄糖氧化酶(GOD)。研究了硅烷化试剂APTES浓度、GA的浓度、最佳给酶量、酶固定化过程中的pH值等因素对固定化酶活性的影响。(2)研究和对比了固定化酶和游离酶的储存稳定性,热稳定性及操作稳定性。研究表明,固定化酶具有优良的储存稳定性,热稳定性及操作稳定性。(3)采用溶胶-凝胶法制备同时具有固定化酶及荧光指示剂钌(Ⅱ)-联吡啶(Ru(bpy)3Cl2)的复合敏感膜,并设计和构建了基于酶催化及荧光猝灭的光纤葡萄糖传感器,利用锁相放大检测技术,研究了传感器性能。研究表明,该传感器检测葡萄糖溶液的浓度范围为100mg/dL～500mg/dL,响应时间35s,同时具有较好的线性检测关系。(4)制备一种新型的同时含有GOD和荧光指示剂Ru(bpy)3Cl2的SiO2荧光纳米复合粒子,初步研究其性能。为研制新型纳米复合光学生物敏感材料打下基础。更多还原

【Abstract】 The fiber optical sensing technology is multidisciplinary cross research fields including material science, information, life science, chemistry and physics. The preparation of fiber optic biosensing materials is one of the key technologies for the development of fiber optic biosensors with high performance. The fiber optic biosensing materials must have high sensitivity, high selectivity, fast response and long lifetime. The detection of glucose is very important in many fields including clinic diagnoses (especially for diabetes), basic medicine research and food industry. The current detection methods for glucose concentration are mainly instrument analysis and electrochemistry sensors, which have the disadvantages such as complex analysis process, low response and high cost. Fiber optic glucose sensor is an effective means for the glucose detection because of its advantages including high precision, fast response, simple operation process and low cost. Therefore, the study of fiber optic glucose sensor is of great importance.In this thesis, silica (SiO2) nanoparticles have been prepared. After the modification, the (SiO2) nanoparticles with amino groups on their surface have been obtained, which were used as the carriers for the immobilization of glucose oxidase (GOD). The optical complex biosensing material containing the immobilization GOD and fluorescent indicator was prepared, which has both the biological catalysis and optical sensitive properties. The fiber optic glucose sensor based on enzyme catalysis and fluorescence quenching was designed and fabricated and its properties have been studied.The main work in this thesis includes:(1) Using Stober method, SiO2 nanoparticles with an average diameter of 100nm were prepared and characterized by SEM. The surface of SiO2 nanoparticle was modified using APTES and GA to produce amino groups, which were used for GOD immobilization. The influence factors on immobilized enzyme activity such as APTES concentration, GA concentration, optimal enzyme concentration, pH value were studied.(2) The stability of immobilized GOD were studied and compared with free enzyme, which indicate that the immobilized GOD is more stable than free enzyme.(3) Using sol-gel method, a new kind of complex optical biosensing membrane was prepared which contains both immobilized GOD and Ru(bpy)3Cl2 indicator. With this biosensing membrane, the fiber optic glucose sensor based on enzymatic catalysis and fluorescence quenching was designed and fabricated. The detection was performed with lock-in technology. The properties of the sensor were studied, showing a good performance with the response time of 35s, glucose concentration detecting range of 100-500mg/dl and good linear relationship between the glucose concentration and phase delay.(4) The complex fluorescent sinica nanoparticles containing both GOD and fluorescent indicator have been prepared and their performance was studied, which will be a contribution to the development of new nanoscale complex optical biosensing materials.更多还原