共查询到20条相似文献,搜索用时 93 毫秒
1.
硅纳米线(SiNW)作为一种新型一维纳米材料,具有高比表面积、高稳定性等特点,在传感器领域得到了重视和研究.随着硅纳米线制备工艺优化、修饰方式多样化,以硅纳米线为载体的生物传感器被应用到了金属离子检测、蛋白质检测等诸多领域,较为优良的生物兼容性为生物学研究中的单细胞动态、实时监测提供了途径,电学、光学等不同检测手段也促... 相似文献
2.
硅纳米线场效应管(silicon nanowire field-effect transistor,SiNW-FET)生物传感器已成功用于蛋白质、核酸、糖类等多种生物分子的检测,并且具有超高灵敏度、高特异性、免标记、即时响应等检测优点。但是,半导体器件德拜屏蔽效应的存在严重影响Si NW-FET生物传感器对血液样品中生物分子检测的灵敏度,尤其对于蛋白质分子的检测,并且其在很大程度上阻碍了Si NW-FET生物传感器的实际应用。目前有效克服德拜屏蔽效应并实现血液样品中蛋白质分子检测的方法主要包括稀释法、去盐法、目标蛋白提纯法、应用渗透性生物分子聚合物层法、裁剪抗体法和适配子替代法。 相似文献
3.
生物传感器概述田桂英(中国农科院科技文献信息中心,100081)生物传感器(Biosensors)是一种新兴的生物技术产品,在分析领域中具有极大的潜力和应用前景。生物传感器是传感器学科中的一个重要分支。八十年代中后期,世界上一些国家,特别是日本和欧美... 相似文献
4.
通过脉冲腐蚀法对硅片进行多孔硅的制备,利用玻片通过对共价法、离子吸附法和APTES修饰的戊二醛交联法3种固定适配子方法的对比,以确定较好的固定青霉素适配子的方法。将适配子固定在多孔硅上后,利用交流阻抗法对加入青霉素前后传感器阻抗值进行测定、对比,构建等效电路并进行阻抗拟合。对多孔硅传感器的Nyqu ist谱图进行分析以确定多孔硅表面成功固定了青霉素适配子,从而证明构建纳米生物传感器成功。传感器的线性检测范围为0.05~0.2 mg/L,检测限为0.05 mg/L。 相似文献
5.
纳米线由于其直径大小接近生物大分子,并且纳米线可以作为电子电路物理组成中的一部分,所以在一定范围通过纳米线将生物细胞分子和电子电路进行对接变得可行。该文主要介绍了生物组件通过纳米线实现对生物分子的传感,通过纳米线对细胞的信号检测,以及在生物分子的输送中的应用等的最新发展。 相似文献
7.
近年来纳米材料的不断引入,为生物传感技术提供了新的研究途径,大大提高了生物传感器的性能。其中,二硫化钼(MoS 2)纳米材料由于比表面积大、带隙可调、电子迁移率高等独特性质,在生物传感器中被广泛应用。本文首先介绍了基于MoS 2纳米材料的电化学、场效应晶体管、表面增强拉曼散射、比色、双模式生物传感器的基本原理、研究进展及性能对比,重点分析了MoS 2纳米复合材料的结构、组分等对传感器灵敏度、检测范围、检测限、特异性等性能的影响,总结了MoS 2生物传感器的优势并对其未来发展趋势进行了展望,为MoS 2生物传感器在生物检测领域的进一步应用以及未来研究方向提供了思路。 相似文献
8.
生物传感器的产生在医药卫生,食品检验和环境监测等领域引起了一场革命,其简单,快速和准确的特点超越了以往诸多分析手段。本文介绍了生物传感器概念,介绍了生物传感器在微生物检测中的应用。 相似文献
9.
DNA传感器是基于DNA分子相互作用原理设计而成的一种新型的检测技术,具有快速,简单等优点,在基因分析及其他应用领域已显示出越来越重要的价值.分子信标是一种具有发卡式结构的寡核苷酸,由于其能够很好地识别单碱基错配序列,基于发卡式DNA的传感器较传统的单链DNA传感器有更好的检测特异性,目前得到广泛的研究.本文介绍了DNA生物传感器及分子信标的有关原理,并着重介绍了发卡式DNA的结构及其在DNA生物传感器中的应用. 相似文献
11.
A top-down nanofabrication approach is used to develop silicon nanowires from silicon-on-insulator (SOI) wafers and involves direct-write electron beam lithography (EBL), inductively coupled plasma-reactive ion etching (ICP-RIE) and a size reduction process. To achieve nanometer scale size, the crucial factors contributing to the EBL and size reduction processes are highlighted. The resulting silicon nanowires, which are 20 nm in width and 30 nm in height (with a triangular shape) and have a straight structure over the length of 400 μm, are fabricated precisely at the designed location on the device. The device is applied in biomolecule detection based on the changes in drain current (I ds), electrical resistance and conductance of the silicon nanowires upon hybridization to complementary target deoxyribonucleic acid (DNA). In this context, the scaled-down device exhibited superior performances in terms of good specificity and high sensitivity, with a limit of detection (LOD) of 10 fM, enables for efficient label-free, direct and higher-accuracy DNA molecules detection. Thus, this silicon nanowire can be used as an improved transducer and serves as novel biosensor for future biomedical diagnostic applications. 相似文献
12.
Surfaces of metallic films and metallic nanoparticles can strongly confine electromagnetic field through its coupling to propagating or localized surface plasmons. This interaction is associated with large enhancement of the field intensity and local optical density of states which provides means to increase excitation rate, raise quantum yield, and control far field angular distribution of fluorescence light emitted by organic dyes and quantum dots. Such emitters are commonly used as labels in assays for detection of chemical and biological species. Their interaction with surface plasmons allows amplifying fluorescence signal (brightness) that accompanies molecular binding events by several orders of magnitude. In conjunction with interfacial architectures for the specific capture of target analyte on a metallic surface, plasmon-enhanced fluorescence (PEF) that is also referred to as metal-enhanced fluorescence (MEF) represents an attractive method for shortening detection times and increasing sensitivity of various fluorescence-based analytical technologies. This review provides an introduction to fundamentals of PEF, illustrates current developments in design of metallic nanostructures for efficient fluorescence signal amplification that utilizes propagating and localized surface plasmons, and summarizes current implementations to biosensors for detection of trace amounts of biomarkers, toxins, and pathogens that are relevant to medical diagnostics and food control. 相似文献
13.
In recent decades, fast advancements in the fields of metal-organic frameworks (MOFs) are providing unprecedented opportunities for the development of novel functional MOFs for various biosensing applications. Exciting progress is achieved due to the combination of MOFs with various functional components, which introduces novel structures and new features to the MOFs-based biosensing applications, such as higher stability, higher sensitivity, higher flexibility, and higher specificity. This review aims to be a comprehensive summary of the most recent advances in the development of functional MOFs for various biosensing applications, placing special attention on important contributions in recent 3 years. In this review, the most recent developments in design and synthesis of functional MOFs for biosensing applications are summarized. MOFs-based biosensing applications are outlined according to the central roles of MOFs in biosensors, which include carriers of sensitive elements, enzyme-mimic elements, electrochemical signaling, optical signaling, and gas sensing. Finally, the current challenges and future development trends of functional MOFs for biosensing applications are proposed and discussed. 相似文献
15.
Plasmonics - In this paper, we report fabrication of a simple, stable, low-cost, and easy-to-fabricate substrate for surface enhanced Raman spectroscopy (SERS) applications. Silicon... 相似文献
16.
以萤火虫发光为例,简述什么是生物传感器;生物传感器的特点和应用效益;生物传感产品在医学诊断、食品、饮料生产企业的卫生检测、环境污染监测等诸多领域中的应用;并对生物传感产品的现有和未来潜在市场作了分析和评价。 相似文献
17.
The optical extinction spectra of micro- and nanoparticles made up of high-contrast dielectrics exhibit a set of very intense peaks due to the excitations of morphology-dependent resonances (MDRs). These kind of resonances are well known at the microscopic scale as whispering gallery modes. In this work, we study numerically the optical spectra corresponding to a core–shell structure composed by an infinite silicon nanowire coated with a silver shell. This structure shows a combination of both excitations: MDRs and the well-known surface plasmon resonances in dielectric metallic core–shell nanoparticles (Ekeroth Abraham and Lester, Plasmon 2012). We compute in an exact form the complete electromagnetic response for both bare and coated silicon nanowires in the range of 24–200 nm of cross-sectional sizes. We take into account an experimental bulk dielectric function of crystalline silicon and silver by using a correction by size of the metal dielectric function. In this paper, we consider small silver shells in the range of 1–10 nm of thickness as coatings. We analyze the optical response in both the far and near fields, involving wavelengths in the extended range of 300–2,400 nm. We show that the MDRs excited at the core are selectively perturbated by the metallic shell through the bonding and antibonding surface plasmons (SPs). This perturbation depends on both the size of the core and the thickness of the shell, and, as a consequence, we get an efficient tuneable and detectable simple system. Our calculations apply perfectly to long nanotubes compared to the wavelength for the two fundamental polarizations (s, p). 相似文献
18.
Described here is the production and characterization of a scalable method to produce 3D structured lithium ion battery anodes using free‐standing papers of porous silicon nanowires (Si‐NW) and graphene nanoribbons (GNRs). Using simple filtration methods, GNRs and Si‐NWs can be entangled into a mat thereby forming Si‐NW GNR papers. This produces anodes with high gravimetric capacity (up to 2500 mA h g ?1) and high areal and volumetric capacities (up to 11 mA h cm ?2 and 3960 mA h cm? 3). The compact structure of the anode is possible since the GNR volume occupies a high proportion of empty space within the composite paper. These Si‐NW/GNR papers have been cycled for over 300 cycles, exhibiting a stable life cycle. Combined with LiCoO 2 nanowires, a full battery is produced with high energy density (386 Wh kg ?1), meeting requirements for high performance devices. 相似文献
19.
We analyze surface-volume reactions in the context of optical biosensors with arrays of reacting zones. For arrays having zones with the same rate constants, we consider a two-dimensional reacting zone boundary definition and quantify ligand depletion with the effective Damköhler number. We use asymptotics to obtain ligand depletion results for the one-dimensional case, and also compute results for the circular reacting zone case. For arrays having zones with different rate constants, depletion effects cannot be expressed as the product of time-dependent and space-dependent terms, and we propose two effective rate constant equations for this case. 相似文献
20.
A label-free optical biosensor based on a nanostructured porous Si is designed for rapid capture and detection of Escherichia coli K12 bacteria, as a model microorganism. The biosensor relies on direct binding of the target bacteria cells onto its surface, while no pretreatment ( e.g. by cell lysis) of the studied sample is required. A mesoporous Si thin film is used as the optical transducer element of the biosensor. Under white light illumination, the porous layer displays well-resolved Fabry-Pérot fringe patterns in its reflectivity spectrum. Applying a fast Fourier transform (FFT) to reflectivity data results in a single peak. Changes in the intensity of the FFT peak are monitored. Thus, target bacteria capture onto the biosensor surface, through antibody-antigen interactions, induces measurable changes in the intensity of the FFT peaks, allowing for a ''real time'' observation of bacteria attachment.The mesoporous Si film, fabricated by an electrochemical anodization process, is conjugated with monoclonal antibodies, specific to the target bacteria. The immobilization, immunoactivity and specificity of the antibodies are confirmed by fluorescent labeling experiments. Once the biosensor is exposed to the target bacteria, the cells are directly captured onto the antibody-modified porous Si surface. These specific capturing events result in intensity changes in the thin-film optical interference spectrum of the biosensor. We demonstrate that these biosensors can detect relatively low bacteria concentrations (detection limit of 10 4 cells/ml) in less than an hour. 相似文献
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