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近几年来,酶传感器、免疫传感器及微生物传感器等发展较为成熟,而DNA生物传感器的研究相对较少.文章从核酸杂交的原理出发介绍了DNA生物传感器的工作原理,举例说明了电化学、光学和声学等几种典型的DNA生物传感器,指出了其固有的优缺点,肯定了DNA传感器发展前景. 相似文献
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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
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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。 相似文献
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适配体传感器在微生物检测中的应用 总被引:1,自引:0,他引:1
适配体是一类特异的核酸序列,具有靶分子广、特异性强、稳定等优点.该类核酸分子在体外通过SELEX(systematic evolution of ligands by exponential enrichment)技术(系统进化的指数富集技术)鉴定和筛选得到.相对于抗体,适配体为诊断和检测分析系统中的识别配基提供了另一个选择.适配体生物传感器是将生物识别元件和信号转换元件紧密结合,从而检测目标化合物的分析装置.适配体生物传感器在微生物检测方面具有分析速度快、灵敏度高、专一性强等特点,在微生物检测中显示出良好的应用前景.介绍了适配体、SELEX流程以及适配体传感器,综述了适配体传感器在微生物检测中的应用. 相似文献
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末端脱氧核酸转移酶(TdT酶)是一种DNA聚合酶,可以催化脱氧核苷酸结合到DNA分子的3'羟基端,并且该反应无需特定的模板。目前,基于末端脱氧核酸转移酶可对模板核酸链的末端进行延伸这一特性,搭载不同的信号输出及扩增方式,构建了一系列的生物传感技术,如电化学生物传感器、荧光生物传感器、表面离子共振生物传感器等。对各类传感器的基本设计原理和应用进行了阐述。根据TdT酶的性质设计的一系列生物传感器具有简单、快速、廉价、灵敏度高、特异性好等优点,实现了对金属离子、病原体、蛋白质等的检测。最后对TdT酶介导的生物传感器目前的研究现状进行了总结并且对TdT酶未来的发展方向进行了展望。 相似文献
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Zijie Chen Zhen Liu Jingjing Liu Xilin Xiao 《Biotechnology and bioengineering》2023,120(12):3501-3517
With the further improvement of food safety requirements, the development of fast, highly sensitive, and portable methods for the determination of foodborne hazardous substances has become a new trend in the food industry. In recent years, biosensors and platforms based on functional nucleic acids, along with a range of signal amplification devices and methods, have been established to enable rapid and sensitive determination of specific substances in samples, opening up a new avenue of analysis and detection. In this paper, functional nucleic acid types including aptamers, deoxyribozymes, and G-quadruplexes which are commonly used in the detection of food source pollutants are introduced. Signal amplification elements include quantum dots, noble metal nanoparticles, magnetic nanoparticles, DNA walkers, and DNA logic gates. Signal amplification technologies including nucleic acid isothermal amplification, hybridization chain reaction, catalytic hairpin assembly, biological barcodes, and microfluidic system are combined with functional nucleic acids sensors and applied to the detection of many foodborne hazardous substances, such as foodborne pathogens, mycotoxins, residual antibiotics, residual pesticides, industrial pollutants, heavy metals, and allergens. Finally, the potential opportunities and broad prospects of functional nucleic acids biosensors in the field of food analysis are discussed. 相似文献
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New methods for automated, direct nucleic acid purification and detection are required for the next generation of unattended environmental monitoring devices. In this study we investigated whether tunable-surface bead chemistry and peptide nucleic acids (PNA) could enhance the recovery and detection of intact rRNA in both test tube and automated suspension array hybridization formats. Intact rRNA was easily captured and detected on PNA-coated Lumavidin beads from 0.1 ng total RNA with a 15-min hybridization in pH 7 buffer, representing 1.7 x 10(3) cell equivalents of total RNA. DNA-conjugated beads in pH 5 hybridization buffer required an overnight hybridization to achieve a detectable signal at 0.1 ng target RNA. Standard DNA hybridization conditions (pH 7) were one order of magnitude less sensitive than the tunable-surface (pH 5) condition. The PNA-conjugated particles were 100x more sensitive than the tunable-surface DNA particles in the automated format, with a detection limit of 0.1 ng total RNA. The detection limits for total RNA on PNA-conjugated microparticles is immediately conducive to the detection and characterization of microorganisms in low-biomass environments or to the identification of rare sequences in a complex sample mixture, without using PCR. 相似文献
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DNA based biosensors 总被引:4,自引:0,他引:4
Compared to advances in enzyme sensors, immunosensors, and microbial biosensors, relatively little work exists on DNA based biosensors. Here we review the DNA based biosensors that rely on nucleic acid hybridization. Major types DNA biosensors--electrochemical, optical, acoustic, and piezoelectric--are introduced and compared. The specificity and response characteristics of DNA biosensors are discussed. Overall, a promising future is foreseen for the DNA based sensor technology. 相似文献
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Fahmida Karim A. N. M. Fakhruddin 《Reviews in Environmental Science and Biotechnology》2012,11(3):261-274
Phenol and its derivatives are widespread contaminants whose sources are both natural and industrial. Phenol is massively produced and used as a starting material for synthetic polymers and fibers. Although phenolic compounds play important biochemical and physiological roles in living systems, their accumulation in the environment as a result of intensive human activity may result in drastic ecological problem. Various analytical techniques are available for the detection of phenol in environmental samples. But they need complex sample pre-treatment so as are time consuming, costly and use heavy devices. On the other hand a biosensor is a device that gives rapid detection, cost effective and easy. A review study was carried out to accumulate the possible biosensors for the detection of phenolic compounds in environmental samples. A number of biological components including microorganisms, enzymes, antibodies, antigens, nucleic acids etc. can be used for the construction of biosensors that was found to detect phenolic compounds. Of all type of biological components microorganisms and enzymes are mostly used. The microorganisms are Pseudomonas, Moraxella, Arthrobacter, Rhodococcus, and Trichosporon. The most used enzymes are tyrosinase, peroxidase, laccase, glucose dehydrogenase, cellobiose dehydrogenase etc. Antibody sensors can detect a very trace level. The biorecognition of DNA biosensors occur by hybridization of DNA. Biosensors are found to work well when the biological sensing element is immobilized. A variety of immobilization techniques were found to use as adsorption, covalent binding, entrapment, cross-linking etc. For immobilization the matrices used was polyvinyl alcohol, Osmium complex, nafion/sol?Cgel silicate, chitosan, silica gel etc. 相似文献
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Sonja Diercks Christine Gescher Katja Metfies Linda K. Medlin 《Journal of applied phycology》2009,21(6):657-668
Biosensors and microarrays are powerful tools for species detection and monitoring of microorganisms. A reliable identification
of microorganisms with probe-based methods requires highly specific and sensitive probes. The introduction of locked nucleic
acid (LNA) promises an enhancement of specificity and sensitivity of molecular probes. In this study, we compared specificity
and sensitivity of conventional probes and LNA modified probes in two different solid phase hybridisation methods: sandwich
hybridisation on biosensors and on DNA microarrays. In combination with DNA-microarrays, the LNA probes displayed an enhancement
of sensitivity, but also gave more false-positive signals. With the biosensor, the LNA probes showed neither signal enhancement
nor discrimination of a single mismatch. In all cases, conventional DNA probes showed equal or better results than LNA probes.
In conclusion, LNA technology may have great potential in methods that use probes in suspension and in gene expressions studies,
but under certain solid surface-hybridisation applications, they do not improve signal intensity. 相似文献
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This review describes recent advances in biosensors of potential clinical applications. Biosensors are becoming increasingly important and practical tools in pathogen detection, molecular diagnostics, environmental monitoring, food safety control as well as in homeland defense. Electrochemical biosensors are particularly promising toward these goals arising due to several combined advantages including low-cost, operation convenience, and miniaturized devices. We review the clinical applications of electrochemical biosensors based on a few selected examples, including enzyme-based biosensors, immunological biosensors and DNA biosensors. 相似文献
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Wang J 《Current issues in molecular biology》1999,1(1-2):117-122
Biosensor devices, based on the conversion of nucleic acid recognition reactions into useful electrical signals, offer considerable promise for DNA diagnostics. The unique hybridization properties of solution-phase PNA can be extrapolated onto transducer surfaces in connection with the design of remarkably specific DNA biosensors. This article reviews the development of PNA biosensors, and discusses common PNA-biosensing protocols along with their prospects in DNA biosensor technology. 相似文献
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Molecular beacons (MBs) are a novel class of nucleic acid probes that become fluorescent when bound to a complementary sequence. Because of this characteristic, coupled with the sequence specificity of nucleic acid hybridization and the sensitivity of fluorescence techniques, MBs are very useful probes for a variety of applications requiring the detection of DNA or RNA. We survey various applications of MBs, including the monitoring of DNA triplex formation, and describe recent developments in MB design that enhance their sensitivity. 相似文献
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Gene specific DNA based sensors have potential applications for rapid and real time monitoring of hybridization signal with the target nucleic acid of pathogens. Different types of DNA based sensors and their applications have been studied for rapid and accurate detection of pathogens causing human diseases. These sensors are based on surface plasmon resonance, quantum-dots, molecular beacons, piezoelectric and electrochemical etc. Curbing epidemics at an early stage is one of the massive challenges in healthcare systems. Timely detection of the causative organism may provide a solution to restrain mortality caused by the disease. With the advent of interdisciplinary sciences, bioelectronics has emerged as an effective alternative for disease diagnostics. Gene specific DNA sensors present themselves as cost-effective, sensitive and specific platforms for detection of disease causing pathogens. The mini review explores different transducer based sensors and their potential in diagnosis of acute and chronic diseases. 相似文献
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Gunnarsson GH Gudmundsson B Thormar HG Alfredsson A Jonsson JJ 《Analytical biochemistry》2006,350(1):120-127
We describe two-dimensional strandness-dependent electrophoresis (2D-SDE) for quantification and length distribution analysis of single-stranded (ss) DNA fragments, double-stranded (ds) DNA fragments, RNA-DNA hybrids, and nicked DNA fragments in complex samples. In the first dimension nucleic acid molecules are separated based on strandness and length in the presence of 7 M urea. After the first-dimension electrophoresis all nucleic acid fragments are heat denatured in the gel. During the second-dimension electrophoresis all nucleic acid fragments are single-stranded and migrate according to length. 2D-SDE takes about 90 min and requires only basic skills and equipment. We show that 2D-SDE has many applications in analyzing complex nucleic acid samples including (1) estimation of renaturation efficiency and kinetics, (2) monitoring cDNA synthesis, (3) detection of nicked DNA fragments, and (4) estimation of quality and in vitro damage of nucleic acid samples. Results from 2D-SDE should be useful to validate techniques such as complex polymerase chain reaction, subtractive hybridization, cDNA synthesis, cDNA normalization, and microarray analysis. 2D-SDE could also be used, e.g., to characterize biological nucleic acid samples. Information obtained with 2D-SDE cannot be readily obtained with other methods. 2D-SDE can be used for preparative isolation of ssDNA fragments, dsDNA fragments, and RNA-DNA hybrids. 相似文献