荧光纳米生物传感器研究进展

荧光纳米生物传感器检测物质具有灵敏度高、响应迅速、抗干扰性强、无需参比电极等特点而被广泛地运用于生物传感技术领域。本文综述了荧光纳米生物传感器种类和特点,介绍了国内外近期在荧光纳米生物传感器及在生物检测方面的一些研究成果及进展,并作了分析比较。着重讨论了纳米粒子荧光生物传感器和光纤纳米荧光生物传感器的特性及其在生物分析中的应用。     

关于双链特异性核酸酶介导的生物传感器研究进展

双链特异性核酸酶（DSN 酶）是一种能高效识别并酶切完全互补配对的 DNA 双链或者 DNA/RNA 杂交双链中的DNA 链,而对单链 DNA 和单 / 双链 RNA 几乎没有作用的核酸酶,所以 DSN 酶在生物和医学等领域有着广泛的应用。目前,基于DSN 酶对单双链核酸不同的切割特点,搭载不同的信号输出及扩增方式,已经建立了一系列生物传感技术,如比色法、荧光法、电化学法等。实现了 mi RNAs、m RNA、重金属离子等一系列生物标志物及食品安全风险因子的检测。另外,DSN 酶与新兴纳米材料搭载的纳米传感器也在 RNA 等物质传感中显示出了极大的分析优势。首先从结构、性质和切割方式 3 个方面介绍了 DSN 酶,并对近年来基于 DSN 酶介导的、具有代表性的生物传感器的组建及应用情况进行了综述,主要是根据不同的信号输出方法对 DSN酶介导的核酸传感器进行归类综述,包括光学传感器、电化学传感器和光磁传感器等。具体综述内容包括,详细地阐述了各种传感器的传感原理,综合比较了各传感器的检测范围及检测灵敏度等,同时还归纳了目前 DSN 酶介导的生物传感器能够检测的靶物质类型,有助于人们以后对 DSN 酶更深层次的使用。最后,对 DSN 酶介导的生物传感器目前存在的不足及今后的发展趋势进行了展望,旨在指导人们在未来使用 DSN 酶介导的生物传感器中能避免相关问题,研发出更快捷、更方便、灵敏度更高的生物传感器。     

关于双链特异性核酸酶介导的生物传感器研究进展

双链特异性核酸酶（DSN 酶）是一种能高效识别并酶切完全互补配对的 DNA 双链或者 DNA/RNA 杂交双链中的DNA 链,而对单链 DNA 和单 / 双链 RNA 几乎没有作用的核酸酶,所以 DSN 酶在生物和医学等领域有着广泛的应用。目前,基于DSN 酶对单双链核酸不同的切割特点,搭载不同的信号输出及扩增方式,已经建立了一系列生物传感技术,如比色法、荧光法、电化学法等。实现了 mi RNAs、m RNA、重金属离子等一系列生物标志物及食品安全风险因子的检测。另外,DSN 酶与新兴纳米材料搭载的纳米传感器也在 RNA 等物质传感中显示出了极大的分析优势。首先从结构、性质和切割方式 3 个方面介绍了 DSN 酶,并对近年来基于 DSN 酶介导的、具有代表性的生物传感器的组建及应用情况进行了综述,主要是根据不同的信号输出方法对 DSN酶介导的核酸传感器进行归类综述,包括光学传感器、电化学传感器和光磁传感器等。具体综述内容包括,详细地阐述了各种传感器的传感原理,综合比较了各传感器的检测范围及检测灵敏度等,同时还归纳了目前 DSN 酶介导的生物传感器能够检测的靶物质类型,有助于人们以后对 DSN 酶更深层次的使用。最后,对 DSN 酶介导的生物传感器目前存在的不足及今后的发展趋势进行了展望,旨在指导人们在未来使用 DSN 酶介导的生物传感器中能避免相关问题,研发出更快捷、更方便、灵敏度更高的生物传感器。     

关于双链特异性核酸酶介导的生物传感器研究进展

双链特异性核酸酶（DSN 酶）是一种能高效识别并酶切完全互补配对的 DNA 双链或者 DNA/RNA 杂交双链中的DNA 链,而对单链 DNA 和单 / 双链 RNA 几乎没有作用的核酸酶,所以 DSN 酶在生物和医学等领域有着广泛的应用。目前,基于DSN 酶对单双链核酸不同的切割特点,搭载不同的信号输出及扩增方式,已经建立了一系列生物传感技术,如比色法、荧光法、电化学法等。实现了 mi RNAs、m RNA、重金属离子等一系列生物标志物及食品安全风险因子的检测。另外,DSN 酶与新兴纳米材料搭载的纳米传感器也在 RNA 等物质传感中显示出了极大的分析优势。首先从结构、性质和切割方式 3 个方面介绍了 DSN 酶,并对近年来基于 DSN 酶介导的、具有代表性的生物传感器的组建及应用情况进行了综述,主要是根据不同的信号输出方法对 DSN酶介导的核酸传感器进行归类综述,包括光学传感器、电化学传感器和光磁传感器等。具体综述内容包括,详细地阐述了各种传感器的传感原理,综合比较了各传感器的检测范围及检测灵敏度等,同时还归纳了目前 DSN 酶介导的生物传感器能够检测的靶物质类型,有助于人们以后对 DSN 酶更深层次的使用。最后,对 DSN 酶介导的生物传感器目前存在的不足及今后的发展趋势进行了展望,旨在指导人们在未来使用 DSN 酶介导的生物传感器中能避免相关问题,研发出更快捷、更方便、灵敏度更高的生物传感器。     

关于双链特异性核酸酶介导的生物传感器研究进展

双链特异性核酸酶(DSN酶)是一种能高效识别并酶切完全互补配对的DNA双链或者DNA/RNA杂交双链中的DNA链,而对单链DNA和单/双链RNA几乎没有作用的核酸酶,所以DSN酶在生物和医学等领域有着广泛的应用。目前,基于DSN酶对单双链核酸不同的切割特点,搭载不同的信号输出及扩增方式,已经建立了一系列生物传感技术,如比色法、荧光法及电化学法等。实现了miRNAs、mRNA及重金属离子等一系列生物标志物及食品安全风险因子的检测。另外,DSN酶与新兴纳米材料搭载的纳米传感器也在RNA等物质传感中显示出了极大的分析优势。首先从结构、性质和切割方式3个方面介绍了DSN酶,并对近年来基于DSN酶介导的、具有代表性的生物传感器的组建及应用情况进行了综述,主要是根据不同的信号输出方法对DSN酶介导的核酸传感器进行归类综述,包括光学传感器、电化学传感器和光磁传感器等。具体综述内容包括,详细地阐述了各种传感器的传感原理,综合比较了各传感器的检测范围及检测灵敏度等,同时还归纳了目前DSN酶介导的生物传感器能够检测的靶物质类型,有助于人们以后对DSN酶更深层次的使用。最后,对DSN酶介导的生物传感器目前存在的不足及今后的发展趋势进行了展望,旨在指导人们在未来使用DSN酶介导的生物传感器中能避免相关问题,研发出更快捷、更方便、灵敏度更高的生物传感器。     

气体生物传感器的应用研究进展

气体生物传感器是基于生物识别、生物转化及气体信号输出的传感器。近年来,由于气体生物传感器具有操作简单、灵敏度高、特异性好等特点,被应用于生物标志物、细胞、蛋白等靶物质的检测中。介绍了气体生物传感器的性质和分类,并分别阐述了蛋白酶介导的气体生物传感器、核酸酶介导的气体生物传感器、模拟酶介导的气体生物传感器和其他气体生物传感器的原理和应用,展望了气体生物传感器的检测手段和应用前景,为气体生物传感器的研究提供了参考。     

二硫化钼纳米材料在生物传感器中的应用

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(MoS₂)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MoS₂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MoS₂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MoS₂生物传感器的优势并对其未来发展趋势进行了展望，为MoS₂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。     

纳米级金微粒在DNA生物传感器研究中的应用

纳米金颗粒具有独特的物理、化学性质和良好的生物兼容性,已广泛应用于生命科学研究中的示踪技术.将该技术与DNA传感器相结合,可显著提高生物传感器的灵敏度,缩短检测时间和提高检测通量,已成为近年来的研究重点.     

生物传感器

生物传感器是对被分析物具有高度的选择性的分析器件。它的敏感元件是生物活性单元,转换元件是物理、化学等转换元件。生物传感器具有检测速度快、灵敏度高、成本低、操作简便以及可进行连续动态监测等优点。本文介绍了生物传感器的发展现状及工作原理,并对生物传感器在环境监测、食物质量和医学方面的应用研究进行了阐述。     

基于环介导等温扩增技术的生物传感器研究进展

环介导等温扩增(loop-mediated isothermal amplification,LAMP)具有快速、等温、特异性高、操作简单等特点,因而近年来基于LAMP原理的生物传感器被广泛开发利用。基于此,对LAMP进行了基本介绍,包括引物设计原理、扩增体系组成及作用、具体扩增过程以及优缺点。然后,重点介绍了基于LAMP的比色生物传感器、荧光生物传感器、电化学生物传感器以及其他种类的生物传感器,并对各类生物传感器的特点进行了总结、比较。最后,剖析了LAMP生物传感器目前的不足,并对其发展方向做出展望,以期为今后研发低成本、高灵敏度、自动化、微型化的LAMP生物传感器提供参考。     

核酸切割酶在病原微生物检测中的研究进展

DNA是遗传信息的重要载体,其空间构象折叠性质使其具有很多的功能。利用核酸切割酶(cleaving DNAzyme)识别特定单链DNA分子并能够切割其中某条单链的性质来构建传感器,将特异性识别过程转化为凝胶电泳表征、释放荧光、比色现象的信号输出,同时能很好的和扩增反应结合来实现信号放大。核酸切割酶通过体外筛选技术获得,可以与靶物质(小分子、蛋白质,甚至整个细胞)特异性结合。由于具有制备简单,易于修饰和良好稳定性等优点,核酸切割酶被用于构建生物传感器以检测病原微生物,已应用到现场检测甚至医疗中的体内检测,结合已经成熟的检测设备血糖仪、横流层析试纸条带进行微生物检测,并广泛地应用到生物传感、食品安全、医疗在内的重要领域中。综述了近年来核酸切割酶在微生物检测中的应用,讨论了核酸切割酶在微生物检测中的切割机理和产物、靶标以及表征手段,探索核酸切割酶在微生物实际检测中的意义。对该技术的发展前景及其面临的问题进行展望,以期核酸切割酶在微生物检测领域能够更好的发展。     

Ultrasensitive carbon nanotube-based biosensors using antibody-binding fragments

We report a method to build ultrasensitive carbon nanotube-based biosensors using immune binding reaction. Here carbon nanotube-field effect transistors (CNT-FETs) were functionalized with antibody-binding fragments as a receptor, and the binding event of target immunoglobulin G (IgG) onto the fragments was detected by monitoring the gating effect caused by the charges of the target IgG. Because the biosensors were used in buffer solution, it was crucial to use small-size receptors so that the charged target IgG could approach the CNT surface within the Debye length distance to give a large gating effect. The results show that CNT-FET biosensors using whole antibody had very low sensitivity (detection limit ∼1000 ng/ml), whereas those based on small Fab fragments could detect 1 pg/ml (∼7 fM level). Moreover, our Fab-modified CNT-FET could successfully block the nontarget proteins and could selectively detect the target protein in an environment similar to that of human serum electrolyte. Significantly, this strategy can be applied to general antibody-based detection schemes, and it should enable the production of label-free ultrasensitive electronic biosensors to detect clinically important biomarkers for disease diagnosis.     

综述与专论: 纳米酶在疾病治疗中的最新进展

纳米酶是具有酶催化活性的纳米材料,对比天然酶,纳米酶具有价格便宜、制备工艺简单、稳定性好、循环利用率高等优势.早期的纳米酶研究主要集中在检测方面,包括检测离子、小分子、核酸、蛋白、癌细胞等,随着对纳米酶的深入了解,研究人员发现纳米酶在疾病治疗领域也具有巨大的应用前景.本论文将介绍纳米酶在杀菌、抗氧化研究领域的最新研究进展.     

Aptamers for pharmaceuticals and their application in environmental analytics

Aptamers are single-stranded DNA or RNA oligonucleotides, which are able to bind with high affinity and specificity to their target. This property is used for a multitude of applications, for instance as molecular recognition elements in biosensors and other assays. Biosensor application of aptamers offers the possibility for fast and easy detection of environmental relevant substances. Pharmaceutical residues, deriving from human or animal medical treatment, are found in surface, ground, and drinking water. At least the whole range of frequently administered drugs can be detected in noticeable concentrations. Biosensors and assays based on aptamers as specific recognition elements are very convenient for this application because aptamer development is possible for toxic targets. Commonly used biological receptors for biosensors like enzymes or antibodies are mostly unavailable for the detection of pharmaceuticals. This review describes the research activities of aptamer and sensor developments for pharmaceutical detection, with focus on environmental applications.     

Electrochemical biosensing with nanoparticles

This minireview looks at the latest trends in the use of nanoparticles (NPs) in electrochemical biosensing systems. It includes electrochemical characterization of NPs for use as labels in affinity biosensors and other applications. DNA analysis involving NPs is one of the most important topics of current research in bionanotechnology. The advantages of the use of NPs in designing novel electrochemical sensors for DNA analysis are reviewed. Electrochemical NPs can also be used in designing immunoassays, offering the possibility of easy, low cost and simultaneous detection of several proteins. Research into NP applications in electrochemical analysis is in its infancy. Several aspects related to sensitivity as well integration of all the assay steps into a single one need to be improved.     

Ethanol increases sensitivity of oxalate oxidase assays and facilitates direct activity staining in SDS gels

Oxalate oxidase, and H₂O₂-generating enzyme, has been characterized from several plants, and is widely used for clinical detection of oxalate. Using a germin-like oxalate oxidase from barley leaves, we have developed and optimized novel methods for measuring oxalate oxidase activity. As oxalate oxidase is SDS-tolerant, its activity can be detected directly in SDS-PAGE gels in the presence of ethanol. This ethanol-dependent method is a hundred times more sensitive than the current methods. Furthermore, ethanol also improves the sensitivity of oxalate oxidase assays performed in solution. We found at least a 10-fold increase in sensitivity in comparison to a current method. The assay in solution is, in addition, useful for detection of oxalate. This elevation in sensitivity may be due to the immobilization of the enzyme in protein precipitates as a result of the treatment with ethanol.     

Progress of new label-free techniques for biosensors: a review

The detection techniques used in biosensors can be broadly classified into label-based and label-free. Label-based detection relies on the specific properties of labels for detecting a particular target. In contrast, label-free detection is suitable for the target molecules that are not labeled or the screening of analytes which are not easy to tag. Also, more types of label-free biosensors have emerged with developments in biotechnology. The latest developed techniques in label-free biosensors, such as field-effect transistors-based biosensors including carbon nanotube field-effect transistor biosensors, graphene field-effect transistor biosensors and silicon nanowire field-effect transistor biosensors, magnetoelastic biosensors, optical-based biosensors, surface stress-based biosensors and other type of biosensors based on the nanotechnology are discussed. The sensing principles, configurations, sensing performance, applications, advantages and restriction of different label-free based biosensors are considered and discussed in this review. Most concepts included in this survey could certainly be applied to the development of this kind of biosensor in the future.     

Advances in Cell‐Free Biosensors: Principle,Mechanism, and Applications

Synthetic biology has promoted the development of biosensors as tools for detecting trace substances. In the past, biosensors based on synthetic biology have been designed on living cells, but the development of cell biosensors has been greatly limited by defects such as genetically modified organism problem and the obstruction of cell membrane. However, the advent of cell‐free synthetic biology addresses these limitations. Biosensors based on the cell‐free protein synthesis system have the advantages of higher safety, higher sensitivity, and faster response time over cell biosensors, which make cell‐free biosensors have a broader application prospect. This review summarizes the workflow of various cell‐free biosensors, including the identification of analytes and signal output. The detection range of cell‐free biosensors is greatly enlarged by different recognition mechanisms and output methods. In addition, the review also discusses the applications of cell‐free biosensors in environmental monitoring and health diagnosis, as well as existing deficiencies and aspects that should be improved. In the future, through continuous improvement and optimization, the potential of cell‐free biosensors will be stimulated, and their application fields will be expanded.     

Colorimetric detection of bisphenol A based on unmodified aptamer and cationic polymer aggregated gold nanoparticles

In this study, a colorimetric method was exploited to detect bisphenol A (BPA) based on BPA-specific aptamer and cationic polymer-induced aggregation of gold nanoparticles (AuNPs). The principle of this assay is very classical. The aggregation of AuNPs was induced by the concentration of cationic polymer, which is controlled by specific recognition of aptamer with BPA and the reaction of aptamer and cationic polymer forming “duplex” structure. This method enables colorimetric detection of BPA with selectivity and a detection limit of 1.50 nM. In addition, this colorimetric method was successfully used to determine spiked BPA in tap water and river water samples.