【作者】 罗颖；

【导师】 蒋健晖； 吴战；

【作者基本信息】 湖南大学 ， 分析化学， 2017， 硕士

【摘要】 随着科学技术的发展,伴随着生命科学的不断发展,人们对生命科学的研究也在不断深入,简单、实时、准确地检测与分析一些在生物化学中起着重要作用的生物分子、酶类、糖等一些与重大疾病相关的信息对医学诊断、临床检测、环境检测与保护等领域都有着至关重要的意义。纳米生物技术是纳米科学与生物技术的交叉学科,其研究涉及到化学、物理、材料、医学、界面科学等众多研究领域。其中纳米材料由于其独特的光学、电子、催化和将生物识别事件转变为电化学或者光学响应的特性,作为一个新颖的、有前途的传感平台在医学诊断、食品分析、生物技术及环境检测与保护等领域都有着广泛的应用。而纳米生物技术的研究中出现的一些新技术,如纳米生物传感器、纳米生物芯片和纳米载体系统等,为纳米技术的发展提供了许多创新性的思路和方向。过氧化氢（H₂O₂）,一种重要的生化分子,在调节各种生理过程中起着非常关键的作用。而葡萄糖（Glucose）是细胞代谢中的主要能量来源,在细胞的自然生长中起着重要作用。细胞内的H₂O₂的紊乱或累积可导致多种严重疾病如中枢神经系统疾病或癌症的产生,而血液中葡萄糖水平的高低与血糖的监测正是与当今全世界都感兴趣的健康问题—糖尿病息息相关,因此如何快速、灵敏地检测H₂O₂和葡萄糖显得尤为迫切。本论文结合二维碳纳米材料-氧化石墨烯和石墨氮化碳,从研究其独特的性质入手,基于这些独特的性质设计了简单、快速、高效、灵敏的新型荧光生物传感器用于检测过氧化氢（H₂O₂）和葡萄糖。研究具体内容概括如下:在第2章中,我们首次建立了一种基于g-C₃N₄纳米片的比率型荧光探针用于过氧化氢和葡萄糖的高灵敏检测。在辣根过氧化物酶（HRP）催化作用下,邻苯二胺（OPD）被H₂O₂氧化为其相应的氧化产物（oxOPD）,由于g-C₃N₄纳米片的高比表面积和大π系统,生成的oxOPD通过氢键和π-π堆积作用力组装于g-C₃N₄纳米片表面,oxOPD不仅可以通过光致诱导电子转移（PET）猝灭g-C₃N₄纳米片的荧光,其本身还可以发出一个新的荧光发射峰。通过测量其比率荧光信号可以高灵敏的检测H₂O₂。由于葡萄糖在葡萄糖氧化酶（GOx）的催化作用下可特异性生成H₂O₂,该方法可进一步应用于葡萄糖的检测。本章发展的分析方法对H₂O₂和葡萄糖的检测下限分别为50 nM和0.4 μM,并且都具有良好的选择性。该传感策略提供了一种涉及生成H₂O₂反应的高通量检测平台。在第3章中,我们在氧化石墨烯（GO）表面组装上荧光标记的DNA,在DNA的引导下直接合成AgNPs得到纳米复合材料（AgNPs-DNA@GO）,由于GO和AgNPs的双重猝灭效应,使得DNA荧光大大减弱。当加入H₂O₂时,H₂O₂与AgNPs相互作用产生羟基自由基（·OH）,能有效腐蚀AgNPs并裂解DNA,从而导致纳米复合材料的解离,最终荧光恢复。通过该方法可以高灵敏的检测H₂O₂并进一步应用于葡萄糖的检测。更多还原

【Abstract】 With the development of science and technology,along with the continuous development of life science,the research of life science is also progressing,simple,real-time,and the accurate detection of important biomolecules,such as protein,enzymes,sugars,and small molecules,has a vital significance to the field of medical diagnosis,food analysis,biotechnology,environmental monitoring and protection etc.Because of their unique optical,electronic,and catalytic response characteristics,nanomaterials have become a new and promising sensing platform for bioanalytical applications.Nanobiosensors,which combined nanomaterials with biosensors,have involved many applications including chemical and biological technology,nanoscience,interface science as well as other interdisciplinary,and embody significant advantages in basic theory of biological sensor.Hydrogen peroxide（H₂O₂）,an important biochemical molecule,plays a critical role in the regulation of various physiological processes.Glucose is the main source of energy in cell metabolism,and plays an important role in cell growth.The intracellular H₂O₂ accumulation or disorder can lead to many serious diseases,such as central nervous system disease or cancer.And monitoring blood glucose level and blood glucose levels in diabetes is closely related to health problems,so the development of a rapid and sensitive nanomaterials-biosensor for detection of H₂O₂ and glucose are important and highly desirable.In this thesis,we uses the two-dimensional nanomaterials of graphene oxide and graphite carbon nitride,starting from the study of its unique properties,and then to the development of simple,fast,efficient and sensitive new sensors to detect H₂O₂ and glucose.The research contents are summarized as following:In the second chapter,we first established a g-C₃N₄ based ratiometric fluorescent probe for highly sensitive detection of hydrogen peroxide and glucose.Under the catalysis of horseradish peroxidase（HRP）,phthalate two amine（OPD）by H₂O₂ oxidation to the corresponding oxidation products（oxOPD）,g-C₃N₄ nanosheets,with high surface area and large π system,generated oxOPD assembled on the surface of g-C₃N₄ nanosheets by hydrogen bonding and π-π stacking interactions,througth the light induced electron transfer（PET）,oxOPD not only quenches the fluorescence of g-C₃N₄ nanosheets,but also emits a new fluorescence peak.Measuring the ratio of fluorescence signal can detect H₂O₂ senstively.Because glucose can produce H₂O₂ under the catalysis of glucose oxidase.the method can be further applied to the detection of glucose.The development of the analysis method for H₂O₂ and glucose in this chapter push detection limit to 50 nM and 0.4μM,respectively,and this method also has good selectivity.The sensing strategy provides a high throughput detection platform involving the H₂O₂-generating reactions.In Chapter 3,we assembled DNA on the surface of graphene（GO）and synthesized AgNPs directly under the guidance of DNA on the surface of GO to obtain nanocomposites（AgNPs-DNA@GO）.In the nanocomposites,due to the double quenching effect of AgNPs,DNA fluorescence greatly weakened.When H₂O₂ is added,H₂O₂ interacts with AgNPs to produce hydroxyl radical（.OH）,which can effectively destroy AgNPs and cleave DNA,which leads to the dissociation of nanocomposites and the final fluorescence recovery.更多还原