生物传感器在POCT中的应用研究

即时检测（POCT）是在病人旁边或现场进行的检测,因其简单、快速、便携且不受场所限制已成为目前体外分子诊断技术发展的一支风向标。而生物传感器以其快速、灵敏、高效、便携及易于自动化、微型化等优点在发展现场即时检测技术中具有非常大的潜力。近年来,随着生物传感技术、互联网技术的发展及各种新技术、新方法的兴起和融合,POCT技术和方法得到了实质性发展。本文简要介绍了生物传感器的分类和生物传感器在POCT中的应用现状,综述了近年来各类生物传感器在面向POCT检测应用的研究进展。生物传感器根据类型主要分为基于微流控芯片的生物传感器、基于纸的生物传感器、基于纳米材料的生物传感器、基于手机检测平台的生物传感器及集成的生物传感器等,并对这些传感器平台在POCT检测方面的应用做了阐述,最后对生物传感器在POCT应用中存在的问题进行了讨论,并对其发展趋势及前景做了展望。     

无酶葡萄糖电化学传感器的研究进展

随着各种新型材料的层出不穷及其在葡萄糖电化学传感器方面应用的发展,无酶葡萄糖电化学传感器的研制成为葡萄糖电化学传感器的另一个研究热点.本文综述了近年来无酶葡萄糖电化学传感器的研究进展,重点介绍了电流型无酶葡萄糖传感器所使用的各种电极材料,总结了最近五年各种新型结构材料在该类传感器研制方面的应用,并对无酶葡萄糖电化学传感器发展方向和趋势进行了展望.     

层层自组装聚电解质膜光纤传感器的制备和应用

在过去几十年中,光纤的应用已经渗透到多个学科领域。光纤的抗电磁干扰、可远程监控、多重监测、体积小及质量轻等特点,使其在传感器研究领域备受关注。聚电解质层层自组装膜构建的光纤传感器自2000年诞生以来,已快速发展成为传感器领域新的研究热点。该类光纤传感器在微量物质的监测方面具有广泛的应用前景。本文从光纤和光纤传感器优点出发,总结了基于层层自组装多层膜的光纤传感器种类、性能、检测原理以及相应的光纤结构和自组装材料;进而结合作者已做的相关工作,论述了在光纤基底上的聚电解质层层自组装及基于自组装膜的光纤传感器的测试;重点综述了近十年层层自组装膜的光纤pH传感器、湿度传感器、气体传感器、生物传感器及其他类型的光纤传感器的制备与应用,并展望了今后聚电解质层层自组装多层膜光纤传感器的发展。     

无酶葡萄糖传感器

葡萄糖传感器在几十年的发展中取得了重大进展,经历了三代基于酶葡萄糖传感器之后,现已进入第四代无酶葡萄糖传感器的发展阶段.本文从基于酶和无酶两类介绍了不同葡萄糖传感器的测试原理,综述了近年来纳米材料在无酶电化学葡萄糖传感器方面应用的主要研究进展,对不同类别纳米材料的制备方法以及所构建传感器的灵敏度、选择性、检测范围和稳定性等进行了评述,分析了制约无酶葡萄糖传感器商业化应用的主要原因.其中,贵金属纳米材料主要讨论了铂、金和钯;过渡金属纳米材料主要讨论了镍、铜以及其氧化物;双金属纳米材料主要讨论了合金和复合物;碳纳米材料主要讨论了单壁(多壁)碳纳米管和石墨烯.此外,本文也对无酶葡萄糖传感器的发展方向和趋势进行了展望.     

手性荧光传感器的研究进展

随着手性化合物在制药、不对称合成、生物科学及临床医学等领域应用的增长,迫切需要发展一种快速、灵敏的对映异构体检测技术。手性荧光传感器引起了人们的高度关注。近年来,发展了很多手性荧光传感器并对手性化合物表现出较高的选择性和灵敏度。该文综述了以1,1'-联-2-萘酚衍生物、杯芳烃衍生物、高分子聚合物、纳米材料、金属有机多孔材料为骨架的手性荧光传感器,总结了其在手性化合物识别中的应用,并展望了手性荧光传感器的发展方向。     

薄膜基荧光气体传感器

薄膜基荧光传感因灵敏度高、可采集信号丰富、实时检测性好和易于器件化等优点备受人们关注,特别是随着微纳米加工、集成制造和物联网技术的发展应用,薄膜基荧光传感器研究已经成为传感器研究的一个重要领域,呈现出广阔的发展前景。 结合课题组工作,本文简要讨论了基于小分子化合物的薄膜基荧光气体传感器在隐藏爆炸物、毒品、挥发性有机污染物检测/监测,重大疾病早期诊断等领域的应用探索。 在此基础上,指出了薄膜基荧光传感器发展面临的问题,评述了薄膜基荧光传感器研究和应用的前景。     

分子印迹聚合物的制备及其传感器应用研究

分子印迹技术于近十年内得到了飞速的发展,已经成为当前研究的热点之一.本文主要介绍了分子印迹聚合物的原理以及一些常用制备方法.分子印迹聚合物的一个重要应用是在化学传感器中作为识别元件,研制稳定、低成本的分子印迹传感器.分子印迹聚合物在传感器领域的应用是分子印迹技术的一个重要方面,本文综述了分子印迹聚合物在化学传感器方面的应用研究现状,并对分子印迹传感器的发展前景进行了评述.     

活体pH实时检测研究进展

酸碱度异常即pH值改变与机体的健康状况有密不可分的关系,活体实时pH检测不仅可以为临床诊疗提供支持信息,而且有助于一些疾病发病机理的研究。本综述详细介绍了pH的定义、pH检测的发展历史、活体实时pH生物传感器所需满足的条件,重点介绍了各类型活体实时pH生物传感器的原理与应用,包括电化学传感器、荧光传感器、光纤传感器以及超声传感器,并对活体实时pH生物传感器的未来发展方向做出展望。     

免标记光学生物传感器研究进展

免标记光学生物传感器因分析样品无需标记、强特异性、动态测量、无损检测、分析速度快等诸多优点,在化学、药学及生物等诸多领域中得到了快速发展和广泛应用。本文重点介绍了当前发展成熟且具代表性的四种免标记光学生物传感器,即表面等离子体共振传感器、光波导光模光谱传感器、椭圆偏振光学传感器以及反射干涉传感器,对每种传感器的原理结构、方法发展及在生化分析等相关领域中的最新应用进行了总结和论述;在此基础上,对它们各自的性能进行了优劣比较;最后对免标记光学生物传感器的发展前景进行了展望。     

可视化柔性可穿戴传感器研究进展

柔性可穿戴传感器具有轻质、共形性好和生物安全性高等特点,在军事、医疗健康和运动等领域展现出广阔的应用前景。可视化是柔性可穿戴传感器的一个重要发展方向,对于丰富传感器功能和扩展其应用领域具有重要意义。本文综述了近年来可视化柔性可穿戴传感器的研究和应用进展,总结了现有的可视化传感器种类及其作用机理,重点介绍了基于发光或变色进行可视化传感的柔性可穿戴传感器。最后,讨论了可视化柔性可穿戴传感器所面临的机遇和挑战。     

“Base Flipping”: Photodamaged DNA–RNA Duplexes Are Poor Substrates for Photoreactivating DNA-Repair Enzymes

What is damaged cannot always be readily repaired. This is observed for particular areas in the genome (mutation hot spots), which are repaired with low efficiency. DNA–DNA duplexes that exist in the B-conformation are repaired relatively efficiently by photolyases. DNA–RNA duplexes, which prefer an A-type conformation are only moderately destabilized by DNA photolesions and are slowly repaired. This suggests that the DNA conformation modulates the necessary “flipping” process for the repair of DNA lesions.     

DNA内电子传递特性的研究现状*

DNA是生物体中储存和传递遗传信息的重要物质。双链DNA分子中碱基对的紧密堆积为电子传递提供了有利条件,DNA内的电子转移与许多生物学功能密切相关,可能诱发遗传信息的错读和引起DNA损伤,导致细胞的突变和癌变。本文介绍了DNA电子传递的多种可能机理,就DNA电子传递的各种理论模型进行了讨论,详细介绍了实验体系的设计和研究方法,分析了各种影响电子传递的因素,对近10多年来DNA电子传递的研究工作进行了综述。     

DNALB膜的AFM形貌观察

DNA分子本身所具有的独特性质使其在生物学、医学和遗传学等领域占有极其重要的位置 ,近年来 ,人们意识到利用 DNA作为模板剂建造具有特殊结构和功能的纳米材料的可行性 [1] ,如 Braun等 [2 ]将寡聚核苷酸连接在两个金电极之间 ,用 DNA分子作为模板剂生长出 1 2 μm长、直径 1 0 0 nm的银纳米线 ;Mirkin等 [3]将 3 和 5 端连有巯基的寡聚核苷酸与金纳米粒子结合 ,通过互补的碱基形成介观尺寸的组装体 ;Alivisatos等 [4]利用 DNA的特点 ,使其与之相连的金纳米粒子按预计的形式排布形成人造分子 .我们尝试利用 LB技术将 DNA分子复合到…     

Properties of hybridized DNA arrays on single-crystalline undoped and boron-doped (100) diamonds studied by atomic force microscopy in electrolytes

Properties of hybridized deoxyribonucleic acid (DNA) arrays on single-crystalline undoped and boron-doped diamonds are studied at the microscopic level by atomic force microscopy (AFM) in buffered electrolytic solutions. DNA is linked to diamond via aminodecene molecules (TFAAD) that are attached to undoped diamonds by a photochemical reaction and via nitrophenyl-diazonium molecules attached electrochemically to boron-doped diamonds. Both H-terminated and oxidized diamond surfaces are used in this process. On H-terminated surfaces, AFM measurements detect compact DNA layers. By analyzing phase and height contrast in AFM, a DNA layer height of 76 A is determined on the photochemically functionalized diamonds and a DNA layer height of up to 92 A is determined on the electrochemically functionalized diamonds. Based on the layer thickness, the DNA chains are tilted under the angle of 31 degrees . The morphology of the DNA layers exhibits long-range (30-50 nm) undulations of 20 A in height and a nanoroughness of 8 A. Using Hertz's model for calculating the contact area of the AFM tip on a DNA layer and a geometrical model of DNA arrangement on diamond yields the DNA density on diamonds of 6 x 10(12) cm(-2) on both photochemically and electrochemically functionalized diamonds. The structure of these dense DNA layers is not significantly influenced by variations in buffer salinity of 1-300 mM NaCl. DNA molecules can be removed from the diamond surface by contact-mode AFM with forces >or= 45 nN and >or= 76 nN on photochemically and electrochemically functionalized diamonds, respectively, indicating that DNA is bonded covalently and stronger on diamond than on gold substrates. The DNA arrangement and bonding strength are similar on oxidized diamond surfaces when using an electrochemical process. On oxidized surfaces after photochemical processing, DNA is bonded noncovalently as deduced from the removal force < 6 nN. The presence of hybridized DNA as well as the selective removal of DNA by AFM scanning are corroborated by fluorescence microscopy.     

Solvent‐free Liquid Crystals and Liquids from DNA

As DNA exhibits persistent structures with dimensions that exceed the range of their intermolecular forces, solid‐state DNA undergoes thermal degradation at elevated temperatures. Therefore, the realization of solvent‐free DNA fluids, including liquid crystals and liquids, still remains a significant challenge. To address this intriguing issue, we demonstrate that combining DNA with suitable cationic surfactants, followed by dehydration, can be a simple generic scheme for producing these solvent‐free DNA fluid systems. In the anhydrous smectic liquid crystalline phase, DNA sublayers are intercalated between aliphatic hydrocarbon sublayers. The lengths of the DNA and surfactant are found to be extremely important in tuning the physical properties of the fluids. Stable liquid‐crystalline and liquid phases are obtained in the ?20 °C to 200 °C temperature range without thermal degradation of the DNA. Thus, a new type of DNA‐based soft biomaterial has been achieved, which will promote the study and application of DNA in a much broader context.     

A column gel electrophoresis-coupled genomic DNA subtractive hybridization technique

We have developed a DNA subtractive hybridization technique especially designed for mammalian genome comparison. The core of this protocol is a newly devised denaturant-containing polyacrylamide gel formed in a glass-column. In this gel system, the following DNA manipulation steps are carried out sequentially: size separation by electrophoresis, heat-denaturation, renaturation, and recovery. In the first step, a mixture of tester and driver DNA fragments are segregated according to their size whilst keeping their double-stranded forms. This reduces the complexity of the original genomic DNA fragments and also segregates DNA fragments having closely related sequences. In the second step, fractionated DNA fragments are quickly denatured and subjected to successive subtractive hybridization in situ by controlling gel temperature in a water bath. In the third step, DNA fragments are recovered by electrophoresis towards the reverse-orientation and are adsorbed onto ion-exchange beads. Two lines of experiments show that our protocol is able to highly enrich or directly extract differences among genomic DNA samples.     

Repair processes on deoxyribonucleic acid

Many cells have the ability to recognize and eliminate damage to their DNA, particularly thymine dimers formed by UV light. The elimination of this damage may be achieved by enzymatic, light-dependent cleavage of the dimers into the monomers (photoreactivation) or more frequently by dark repair, in which the damaged part is completely removed from the, DNA. In this repair process, the DNA is incised by an endonuclease in the immediate vicinity of the thymine dimers. Oligonucleotides containing the thymine dimer are removed hydrolytically from the DNA by the 5→3′ exonuclease activity of DNA polymerase I (Kornberg enzyme). The resulting gaps are immediately closed by a de novo synthesis with the aid of the same DNA polymerase I, the complementary strand serving as a template (excision repair). The final step is the formation of the phosphodiester bond between the newly synthesized DNA fragment and the old DNA strand by a DNA ligase. Xeroderma pigmentosum patients lack the endonuclease as a result of a genetic defect; they therefore cannot eliminate thymine dimers from their DNA, and are extremely sensitive to sunlight. All information so far suggests that genetic recombination and DNA repair are performed by the same enzyme system.     

脱氧核糖核酸电分析化学研究进展

就DNA电分析化学研究及其应用方面进行综述，主要叙述了DNA的各种电分析化学方法，以及DNA电化学传感器的原理，应用以及发展，本文引用文献77篇。     

Assembly of DNA triangles mediated by perylene bisimide caps

Perylene bisimides (PBI) have been synthetically incorporated as caps onto a Y-shaped DNA triple strand. These PBI caps serve as "sticky" ends in the spontaneous assembly of larger DNA ensembles, linking the triangular DNA through stacking interactions. This, in turn, yields a hypsochromic shift in the absorption and a red shift in the fluorescence as characteristic optical readouts. This assembly occurs spontaneously without any enzymatic ligation process and without the use of overhanging DNA as sticky ends. Instead, dimerizations of the PBI chromophores in the assembly are controlled by the DNA as a structural scaffold. Thereby, the PBI-driven assembly is fully reversible. Due to the fact that PBI dimerization does not occur in the single strand, the aggregates can be destroyed by thermal dehybridization of the DNA scaffold and reassembled by reannealing of the DNA construct. In view of the fact that PBI forms stable radical anions, the presented DNA architectures are not only interesting optical biomaterials, but are also promising materials for molecular electronics with DNA.