生物电化学简介

简单介绍了生物电化学研究领域的概况。包括：生物膜与生物界面模拟研究（ＳＡＭ膜模拟生物膜的电化学、液／液界面模拟生物膜的电化学），用于生命科学的电化学技术（电脉冲基因直接导入、电场加速作物生长、癌症的电化学疗法、电化学控制药物释放、在体研究的电化学方法、生物分子的电化学行为）和电化学生物传感器（酶电极传感器、微生物电极传感器、电化学免疫传感器、组织电极与细胞器电极传感器、电化学ＤＮＡ传感器）。     

微机械加工的微结构型电化学传感器

微结构型电化学传感器是应用发展中的微机械加工技术结合传统的电化学传感技术创立的新一代的电化学传感器，而微机械加工技术与多种高新技术学科的相互交叉，又将拓宽微结构型电化学传感器研究的新领域。本文在简要介绍微机械加工技术的基础，对前类微结构型电化学传感器作了归纳，其中也提及作者年来来的研究工作，并对后者作一展望性评述。     

纳米材料应用于无酶电化学生物传感器的研究进展

无酶电化学生物传感器具有环境适用性强、稳定性高、材料简单易得、灵敏度高、检测限低等特点，近年来受到研究者广泛关注。纳米材料有类酶活性，表现出类似天然酶的酶促反应动力学和催化机理，且能够增强界面吸附性能，增加电催化活性，并促进电子转移动力学，从而广泛应用于无酶电化学生物传感器。本文探索了具有电催化活性的纳米材料及其修饰电极的制备方法，介绍了无酶电化学传感器在医疗诊断、食品检测、环境检测以及其他领域中的应用，讨论了开发基于纳米材料的电化学传感器的未来机遇和挑战。     

聚四氨基酞菁铜微型传感器及其在一氧化氮测定中的应用

利用电化学聚合的方法制备了聚四氨基酞菁酮微型传感器，并探讨了微型传感器对一氧化氮（ＮＯ）的电化学响应。结果表明，电化学聚合Ｃｕ（ＴＡＰｃ）微型传感器对ＮＯ具有良好的催化氧化作用。     

固态电化学气体传感器的最新发展

本文从固态电化学气体传感器的一般原理,着重评述了固态电化学气体传感器的分类依据及每类传感器的发展;并对极有应用潜力的第三类电化学气体传感器的发展水平及其方向进行了论述。     

我国电化学气体传感器技术达到了国际先进水平

不久前，中国科学院长春应用化学研究所承担的电化学气体传感器研究项目通过了技术鉴定。鉴定意见认为这一研究成果标志着中国电化学气体传感器技术达到了国际先进水平。     

纳米电化学生物传感器

纳米电化学生物传感器是将纳米材料作为一种新型的生物传感介质,与特异性分子识别物质如酶、抗原/抗体、DNA等相结合,并以电化学信号为检测信号的分析器件。本文简要介绍了生物传感器的分类和纳米材料在电化学生物传感器中的应用及其优势,综述了近年来各类纳米电化学生物传感器在生物检测方面的研究进展,包括纳米颗粒生物传感器,纳米管、纳米棒、纳米纤维与纳米线生物传感器,以及纳米片与纳米阵列生物传感器等。     

海洋毒素电化学生物传感器

由藻类产生的海洋毒素对人类健康和环境安全构成了较大威胁,对其进行快速准确的检测是减小海洋毒素危害的有效手段之一。电化学生物传感器具有快速简便、灵敏度高、检测限低和成本低等特点,为检测海洋毒素提供了新的技术途径。目前,应用于海洋毒素检测中的电化学生物传感器主要有免疫传感器、酶传感器和DNA传感器等。本文综述了迄今为止国内外海洋毒素电化学生物传感器研究所取得的成果,并对其当前研究存在的问题和未来发展趋势进行探讨和展望。     

聚吡咯修饰烟酸电位型生物传感器的制备与性能研究

用循环伏安法制备了对烟酸有良好Ｎｅｒｎｓｔ电位响应的聚吡咯修饰烟酸化学传感器。传感器的响应是基于烟酸根离子在掺杂了烟酸的聚吡咯膜中掺杂＝释放平衡。研究了聚合条件对传感器电化学性能的影响,表征了传感器的电化学特性。     

玻璃载体表面脱氧核糖核酸的固定及其化学发光检测

用硅烷化偶联剂把ＤＮＡ直接共价固定在载玻片表面，将辣根过氧化物酶标记的探针与之进行核酸杂交，杂交后用增强的化学发光检测。方法的检出限为７５ｐｇ。研究了ＤＮＡ分子固定在玻璃载体表面的各种条件，并建立了在玻璃载体表面进行核酸杂交的体系，为研究光纤ＤＮＡ生物传感器打下了基础。     

Electrochemical DNA-sensors for determining biologically active low-molecular compounds

General tendencies of the progress in the development of electrochemical DNA sensors devoted to the determination of biologically active low-molecular compounds have been considered on the base on own authors investigations and literary data. The ways for the generation of analytical signal of DNA sensors are considered depending on the mechanism of DNA- analyte interaction. The application of DNA sensors for the determination of pharmaceuticals (anthracyclines,. phenothiazines, sulfonylamides etc.) and environmental pollutants is described. The prospects of DNA sensor development are discussed.     

Fluorescent DNA-based enzyme sensors

Fluorescent sensors that make use of DNA structures have become widely useful in monitoring enzymatic activities. Early studies focused primarily on enzymes that naturally use DNA or RNA as the substrate. However, recent advances in molecular design have enabled the development of nucleic acid sensors for a wider range of functions, including enzymes that do not normally bind DNA or RNA. Nucleic acid sensors present some potential advantages over classical small-molecule sensors, including water solubility and ease of synthesis. An overview of the multiple strategies under recent development is presented in this critical review, and expected future developments in microarrays, single molecule analysis, and in vivo sensing are discussed (160 references).     

Past, present and future of nucleic acids electrochemistry

Electrochemistry of nucleic acids was discovered about 40 years ago. During the first 15 years electrochemistry brought early evidence of DNA premelting and polymorphy of the DNA double helix. At present electrochemical methods working with stationary electrodes are able to detect DNA at attomol and in some cases, even at lower levels. A great progress in the development of electrochemical sensors for DNA hybridization and DNA damage achieved in recent years suggests that these sensors may soon become important tools in medicine and other areas of practical life of the 21st century.     

A general approach for rational design of fluorescent DNA aptazyme sensors based on target-induced unfolding of DNA hairpins

DNA aptazymes are allosteric DNAzymes activated by the targets of DNA aptamers. They take the advantages of both aptamers and DNAzymes, which can recognize specific targets with high selectivity and catalyze multiple-turnover reactions for signal amplification, respectively, and have shown their great promise in many analytical applications. So far, however, the available examples of DNA aptazyme sensors are still limited in utilizing only several DNAzymes and DNA aptamers, most likely due to the lack of a general and simple approach for rational design. Herein, we have developed such a general approach for designing fluorescent DNA aptazyme sensors. In this approach, aptamers and DNAzymes are connected at the ends to avoid any change in their original sequences, therefore enabling the general use of different aptamers and DNAzymes in the design. Upon activation of the aptazymes by the targets of interest, the rate of fluorescence enhancement via the cleavage of a dually labeled substrate by the active aptazymes is then monitored for target quantification. Two DNAzymes and two aptamers are used as examples for the design of three fluorescent aptazyme sensors, and they all show high selectivity and sensitivity for the detection of their targets. More DNA aptazyme sensors for a broader range of targets could be developed by this general approach as long as suitable DNAzymes and aptamers are used.     

G-四链体-氯化血红素DNA酶在传感器设计中的应用

G-四链体-氯化血红素(hemin)DNA酶是一种由特定的核酸G-四链体与hemin结合后形成的具有过氧化物酶活性的人工模拟酶。作为一类重要的DNA酶,G-四链体-hemin DNA酶近年来在分析化学领域受到了越来越多的关注。目前这类DNA酶已被用在了多种传感器,包括金属离子传感器、适配体传感器、酶传感器、DNA传感器及药物传感器的设计当中。本文对G-四链体-hemin DNA酶在传感器设计中的应用进行了系统的介绍和评述,并对其未来的发展进行了初步的展望。     

DNA hybridization chain reaction and DNA supersandwich self-assembly for ultrasensitive detection

The fabrication of sensitive sensors with high selectivity is highly desirable for the detection of some important biomarkers,such as nucleic acids,proteins,small molecules and ions.DNA hybridization chain reaction(HCR) and DNA supersandwich self-assembly(SSA) are two prevalent enzyme-free signal amplification strategies to improve sensitivity of the sensors.In this review,we firstly describe the characteristics about DNA HCR and DNA SSA,and then summarize the advances in the one-dimensional DNA nanostructures assisted by HCR and SSA.This review has been divided into three parts according to the two signal amplification methods and highlights recent progress in these two strategies to improve the detection sensitivity of proteins,nucleic acids,small molecules and ions.     

Magnetic beads as versatile tools for electrochemical DNA and protein biosensing

Magnetic beads (MBs) are versatile tools in the separation of nucleic acids, proteins and other biomacromolecules, their complexes and cells. In this article recent application of MBs in electrochemical biosensing and particularly in the development of DNA hybridization sensors is reviewed. In these sensors MBs serve not only for separation but also as a platform for optimized DNA hybridization. A hybridization event is detected separately at another surface, which is an electrode. The detection is based either on the intrinsic DNA electroactivity or on various kinds of DNA labeling, including chemical modification, enzyme tags, nanoparticles, electroactive beads, etc., greatly amplifying the signals measured. In addition to DNA hybridization, other kinds of biosensing in combination with MBs, such as DNA-protein interactions, are reviewed.     

Critical review of bio/nano sensors for arsenic detection

Detection of arsenic is a long-standing challenge in environmental analytical chemistry. In recent years, using biomolecules and nanomaterials for sensing arsenic has been growingly reported. In this article, this field is critically reviewed based on some recent fundamental understandings including interactions between arsenic and gold, thiol, and DNA aptamers. First, taking advantage of the adsorption of As(III) on noble metal surfaces such as silver and gold, sensors were developed based on surface enhanced Raman spectroscopy, electrochemistry and colorimetry. In addition, by functionalizing metal nanoparticles with thiol containing molecules, As(III) induced aggregation of the particles based on As(III)/thiol interactions. As(V) interacts with metal oxides strongly and competitive sensors were developed by displacing pre-adsorbed DNA oligonucleotides. A DNA aptamer was selected for As(III) and many sensors were reported based on this aptamer, although careful binding measurements indicated that the sequence has no affinity towards As(III). Overall, bio/nano systems are promising for the detection of arsenic. Future work on fundamental studies, searching for more specific arsenic binding materials and aptamers, incorporation of sensors into portable devices, and more systematic test of sensors in real samples could be interesting and useful research topics.     

E-DNA sensors for convenient, label-free electrochemical detection of hybridization

We review the development of reagentless, electrochemical sensors for the sequence-specific detection of nucleic acids that are based on the target-induced folding or unfolding of electrode-bound oligonucleotides. These devices, which are sometimes termed E-DNA sensors, are comprised of an oligonucleotide probe modified on one terminus with a redox reporter and attached to an electrode at the other. Hybridization of this probe DNA to a target oligonucleotide influences the rate at which the redox reporter collides with the electrode, leading to a detectable change in redox current. Because all sensing elements of this method are strongly linked to the interrogating electrode, E-DNA sensors are label-free, operationally convenient and readily reusable. As E-DNA signaling is predicated on a binding-specific change in the dynamics of the probe DNA (rather than simply monitoring the adsorption of a target to the sensor surface) and because electroactive contaminants (interferents) are relatively rare, this class of sensors is notably resistant to false positives arising from the non-specific adsorption of interferents, and performs well even when challenged directly with blood serum, soil and other complex sample matrices. We review the history of and recent advances in this promising DNA and RNA detection approach.     

Review: Carbon nanotube based electrochemical sensors for biomolecules

Carbon nanotubes (CNTs) have been incorporated in electrochemical sensors to decrease overpotential and improve sensitivity. In this review, we focus on recent literature that describes how CNT-based electrochemical sensors are being developed to detect neurotransmitters, proteins, small molecules such as glucose, and DNA. Different types of electrochemical methods are used in these sensors including direct electrochemical detection with amperometry or voltammetry, indirect detection of an oxidation product using enzyme sensors, and detection of conductivity changes using CNT-field effect transistors (FETs). Future challenges for the field include miniaturizing sensors, developing methods to use only a specific nanotube allotrope, and simplifying manufacturing.