基于石墨烯场效应晶体管的核酸生物传感器研究

发布时间：2018-04-19 10:00

本文选题：生物传感器 + 场效应晶体管　；参考：《湖北中医药大学》2015年硕士论文

【摘要】：核酸分子的检测可以为分子生物学研究、遗传病诊断和环境监测等提供非常有用的信息。虽然目前已有多种检测核酸分子的方法,但是研发超灵敏度、高选择性的核酸检测方法仍然十分重要。随着现代电子技术及生物技术的迅速发展,生物传感器的研究越来越热门,这个新兴的交叉学科领域将在生命科学研究及医学检测中发挥越来越重要的作用。生物传感器是将生物识别元件与适当的信号转导元件组合在一起用来可逆和选择性地检测各种类型样品中的生物化学物质的浓度或活性的装置。生物传感器是一类以生物识别元件(如核酸、抗体、酶、细胞等)作为生物敏感单元,对目标待测物具有高度选择性的特殊装置。然后利用信号转导元件将生物信号转换成可以检测的信号,而实现对待测目标物的检测。纳米场效应晶体管(field effect transistor,FET)生物传感器是近年发展起来的一种基于纳米材料的新型生物传感器。一方面,它具有高度的微型化和集成化的潜力而吸引了生命科学领域研究者的广泛关注。另一方面,由于纳米材料具有独特的理化性质,如表面效应、微尺寸效应、量子效应和宏观量子隧道效应等,使得纳米FET生物传感器与传统的检测技术相比,具有灵敏度和选择性高、分析速度快、免标记、操作简单、试剂消耗少等特点,非常适用于生物分子的检测,可以预见它在医学检测中会发挥越来越大的作用。石墨烯是一种由碳原子构成的单层片状结构的二维纳米材料。石墨烯具有独特的理化性质:大的体表比、高的电子迁移率、极好的热电传导性、高机械强度等,石墨烯这些独特的性质可用来提高纳米FET生物传感器检测的灵敏度和选择性。本文将纳米材料石墨烯应用于场效应晶体管生物传感器上,构建基于石墨烯的FET生物传感器。在石墨烯表面固定上与靶序列特异的探针分子,利用核酸-核酸分子杂交的原理和通过检测杂交前后电信号的变化就可以达到高灵敏度和高选择性地检测核酸分子的目的。具体内容如下:第一章:基于肽核酸修饰的石墨烯场效应晶体管DNA生物传感器按照标准的微纳加工技术制备场效应晶体管,利用98%的肼化学还原氧化石墨烯(graphene oxide,GO)制备得到还原的氧化石墨烯(reduced graphene oxide,R-GO),将R-GO悬液滴涂到场效应晶体管器件表面构建石墨烯FET生物传感器。然后通过1-芘丁酸-琥珀酰亚胺酯(1-pyrenebutanoic acid succinimidyl ester,PASE)将肽核酸(peptide nucleic acid,PNA)探针固定在场效应晶体管生物传感器上的R-GO表面,通过检测PNA-DNA杂交前后电信号的变化进行DNA的检测。实验得到的DNA检测限可低至100 fmol/L,该灵敏度比已报道的基于DNA-DNA杂交的石墨烯场效应晶体管DNA生物传感器的灵敏度提高了一个数量级。另外,该R-GO场效应晶体管生物传感器还能够区分互补DNA、非互补DNA和单碱基错配的DNA,具有很好的选择性。同时,该DNA生物传感器还能够重复使用。终上所述,构建的R-GO场效应晶体管DNA生物传感器具有超高的灵敏度、高选择性及重复使用性,表明其作为一个床旁检测工具在疾病诊断中具有潜在的应用前景。第二章:基于金纳米颗粒修饰的石墨烯场效应晶体管mi RNA生物传感器按上述方法制备石墨烯场效应晶体管生物传感器,利用氯金酸溶液将金纳米颗粒(gold nanoparticles,Au NPs)沉积在石墨烯表面,构建金纳米颗粒修饰的石墨烯场效应晶体管生物传感器。将PNA探针通过化学共价键固定在Au NPs表面,加入mi RNA与PNA探针杂交,通过检测该石墨烯FET生物传感器杂交前后电信号的变化就可以来检测mi RNA。该石墨烯FET生物传感器对mi RNA的检测限可低至10 fmol/L,且该生物传感器能够区分互补mi RNA、非互补mi RNA和单碱基错配的mi RNA。此外,本章还尝试将该具有高灵敏度和高选择性的石墨烯FET生物传感器用于血清样品中mi RNA的检测,结果表明该石墨烯FET生物传感器也能用于实际样品的检测。相信该方法为mi RNA的检测将提供一种新型的检测平台。
[Abstract]:For the research of molecular biology can detect nucleic acid molecules, provide very useful information for genetic disease diagnosis and environmental monitoring. Although the detection of nucleic acid molecules has a variety of methods, but the development of ultra sensitivity, nucleic acid detection method of high selectivity is still very important. With the rapid development of modern electronic technology and biological technology, biosensors and more popular, this emerging interdisciplinary field will play an increasingly important role in the research of life science and medicine detection. Biosensor is the biological recognition element and proper signal transduction components in the device to the concentration or activity of chemical compounds of biological reversible and selective detection of various types of biological samples. The sensor is a kind of biological recognition element (such as nucleic acids, antibodies, enzymes, cell etc.) as a biological sensing element, on the target to be measured The special device is highly selective. Then the signal transduction components of biological signals into signals can be detected, and which is used to detect the target. The nano field effect transistor (field effect, transistor, FET) biosensor is a recently developed new biosensor based on nano materials. On the one hand, it with the integration and miniaturization of high potential has attracted widespread attention in the field of life science research. On the other hand, because of the nano materials have unique physical and chemical properties, such as surface effect, small size effect, quantum effect and macroscopic quantum tunneling effect, which makes the detection technology of nano FET biosensor compared with the traditional, with high sensitivity and selectivity, fast analysis, label free, simple operation, less reagent consumption and other characteristics, is very suitable for the detection of biological molecules, it can be predicted In medical detection will play an increasing role. Graphene is a two-dimensional material composed of carbon atoms of the single sheet structure. Graphene has unique physicochemical properties: high surface ratio, high electron mobility, excellent thermoelectric conductivity, high mechanical strength, these unique graphene the properties of nano FET can be used to improve the sensitivity and selectivity of the biosensor. The nano materials applied to graphene field effect transistor biosensor, FET biosensors based on graphene. The probe molecule in the fixed on the surface of graphene and target sequence specific changes, using the principle of nucleic acid hybridization and by detection of signals before and after hybridization can achieve high sensitivity and high selectivity for detection of nucleic acid molecules. The specific contents are as follows: the first chapter: graphene based on modified peptide nucleic acid Field effect transistor DNA biosensor in accordance with the standards of micro nano machining technique field effect transistor, reduction of graphene oxide with hydrazine chemistry 98% (graphene oxide GO) was prepared by oxidation of reduced graphene (reduced graphene, oxide, R-GO, R-GO) suspended droplet coating field effect transistor device surface construction of graphene FET biosensor. Then 1- Pyrenebutyric acid - hydroxysuccinimide ester (1-pyrenebutanoic acid succinimidyl ester PASE (peptide nucleic) the peptide nucleic acid acid, PNA) R-GO field effect transistor probe fixed surface biological sensor, detection of DNA by detecting the changes of PNA-DNA before and after hybridization signal. The DNA detection limit can be obtained as low as 100 fmol/L, the sensitivity compared with the reported sensitivity of graphene DNA-DNA hybrid field effect transistor DNA biosensor based on an order of magnitude increase. Outside, the R-GO field effect transistor biosensor is also able to distinguish between complementary DNA, non complementary DNA and single base mismatch DNA, has good selectivity. At the same time, the DNA biosensor can be used repeatedly. In the end, the construction of R-GO field effect transistor DNA biosensor with ultra high sensitivity, high selectivity and reusability, that has a potential application prospect in the diagnosis of diseases as a bedside detection tool. The second chapter: graphene gold nanoparticles modified field effect transistor mi RNA biosensor according to the preparation methods of graphene field-effect transistor biosensor based on using chloroauric acid solution of gold nanoparticles (gold nanoparticles, Au NPs particles) deposited on the surface of graphene, the construction of gold nanoparticles modified graphene field-effect transistor biosensor. The PNA probe by chemical covalent immobilization in Au NPs The surface of RNA and PNA MI, joined the hybridization probe, by detecting the changes before and after the graphene FET hybrid biological sensor signals can be detected mi RNA. the graphene FET biosensor for the detection of MI RNA limit can be as low as 10 fmol/L, and the biological sensor can distinguish the complementary mi RNA, MI RNA and single non complementary mismatched mi RNA. in addition, this chapter will try this with high sensitivity and high selectivity of graphene FET biosensors for the detection of MI RNA in serum samples, the results show that the graphene FET biosensor can be applied to the actual sample testing for the detection of MI RNA. I believe that this method will provide a the new testing platform.

【学位授予单位】：湖北中医药大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TP212.3;R440

【共引文献】