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Introduction The analysis of DNA sequence and DNA mutant detection play fundamental roles in the rapid development of molecular diagnostics and in the anticancer drug screening. Therefor many detection techniques of DNA sequence have been developed in recent years. These techniques mainly depend on the nucleic acid hybridization1 and their sensitivities are related to the specific activity of the label linked to the DNA probe. The degree of hybridization of probe to its complementary DN… 相似文献
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Nikolay A. Grigorenko Dr. Christian J. Leumann Prof. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(3):639-645
Three 2′‐phenanthrenyl‐C‐deoxyribonucleosides with donor (phenNH2), acceptor (phenNO2), or no (phenH) substitution on the phenanthrenyl core were synthesized and incorporated into oligodeoxyribonucleotides. Duplexes containing either one or three consecutive phenR residues, which were located opposite each other, were formed. Within these residues, the phenR residues are expected to recognize each other through interstrand stacking interactions, in much the same way as described previously for biphenyl DNA. The thermal, thermodynamic, and fluorescence properties of such duplexes were determined by UV melting analysis and fluorescence spectroscopy. Depending on the nature of the substituent, the thermal stability of single‐modified duplexes can vary between ?2.7 to +11.3 °C in Tm and that of triple‐modified duplexes from +7.8 to +11.1 °C. Van′t Hoff analysis suggested that the observed higher thermodynamic stability in phenH‐ and phenNO2‐containing duplexes is of enthalpic origin. A single phenH or phenNO2 residue in a bulge position also stabilizes a corresponding duplex. If a phenNO2 residue is placed in a bulge position next to a base mismatch this can lead, in a sequence‐dependent manner, to duplex destabilization. The phenNO2 residue was found to be a highly efficient (10–100‐fold) quencher of phenH and phenNH2 fluorescence if placed in the opposite position to the fluorophores. When phenH and phenNH2 residues were placed opposite each other, efficient quenching of phenH and enhancement of phenNH2 fluorescence was found, which is an indicator for electron‐ or energy‐transfer processes between the aromatic units. 相似文献
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巯基化合物自组装单分子层的研究进展 总被引:20,自引:1,他引:20
超薄层有机材料的制备与研究 ̄[1]受到人们的广泛关注,有关研究结果和进展正在不断丰富着人类对表面结构与性质关系的理解和认识。与其它制备单分子层的技术相比,自组装技术是一种较新的制备方法,在80年代后期,迅速成为有关学科的研究焦点。采用此技术制备的超薄层体系主要有两类:一类是巯基化合物在金、银、铜、铂表面吸附形成的单层 ̄[2,3],一类是在硅、玻璃、金属氧化物表面通过硅烷化反应形成的单层 ̄[4]。其中,硫醇类分子自组装单层(self-assembledmonolayer,3AM)是被研究得最为广泛和深入的体系。本文主要综述十年来巯基化合物SAM的研究进展。 相似文献
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Carla T. Cioffi Dr. Amit Palkar Dr. Frederic Melin Dr. Amar Kumbhar Luis Echegoyen Prof. Dr. Manuel Melle‐Franco Francesco Zerbetto Prof. Dr. G. M. Aminur Rahman Dr. Christian Ehli Vito Sgobba Dr. Dirk M. Guldi Prof. Dr. Maurizio Prato Prof. Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(17):4419-4427
Don't cry! The attachment of ferrocene moieties on the surface of carbon nano‐onions influences the electrochemical properties of these moieties and the photophysical properties of the carbon nano‐onions (see figure). Quantum chemical calculations confirm that the spectral properties of carbon nano‐onions depend on their size and the degree of functionalisation.
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Solution‐Processed Two‐Dimensional MoS2 Nanosheets: Preparation,Hybridization, and Applications 下载免费PDF全文
Xiao Zhang Zhuangchai Lai Chaoliang Tan Prof. Hua Zhang 《Angewandte Chemie (International ed. in English)》2016,55(31):8816-8838
As one member of the emerging class of ultrathin two‐dimensional (2D) transition‐metal dichalcogenide (TMD) nanomaterials, the ultra‐thin MoS2 nanosheet has attracted increasing research interest as a result of its unique structure and fascinating properties. Solution‐phase methods are promising for the scalable production, functionalization, hybridization of MoS2 nanosheets, thus enabling the widespread exploration of MoS2‐based nanomaterials for various promising applications. In this Review, an overview of the recent progress of solution‐processed MoS2 nanosheets is presented, with the emphasis on their synthetic strategies, functionalization, hybridization, properties, and applications. Finally, the challenges and opportunities in this research area will be proposed. 相似文献
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新型DNA电化学传感器的研制及其用于DNA氧化性损伤检测的研究 总被引:4,自引:1,他引:3
用溶胶-凝胶法在玻碳电极上制备了纳米多孔羟基磷灰石(HAp)-聚乙烯醇(PVA)涂层膜固定双链DNA,得到了一种新型DNA电化学传感器,检测了由Fenton反应引起的DNA氧化性损伤.结果表明,一定量浓度的抗坏血酸(AA)能加速Fenton反应的进行,使DNA损伤很快达到极限;损伤试剂中Fe2+的浓度越大,产生的羟基自由基(OH.)越多,对DNA的损伤就越严重;损伤试剂中EDTA的浓度越小,溶液中游离的Fe2+以及与DNA键合的Fe2+的浓度则相对越大,对DNA的损伤也就越严重. 相似文献
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A novel NH2+ ion implantation‐modified indium tin oxide (NH2/ITO) electrode was prepared. Acid‐pretreated, negatively charged MWNTs were firstly modified on the surface of NH2+ ion implantation electrode, then, positively charged Mb was adsorbed onto MWNTs films by electrostatic interaction. The assembly of MWNTs and Mb was characterized with electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV). The immobilized Mb showed a couple of quasireversible cyclic voltammetry peaks in pH 7.0 phosphate buffer solution (PBS). The apparent surface concentration of Mb at the electrode surface was 1.06×10?9 mol cm?2. The Mb/MWNTs/NH2/ITO electrode also gave an improved electrocatalytic activity towards the reduction of hydrogen peroxide. The catalysis currents increased linearly to the H2O2 concentration in a wide range from 9×10?7 to 9.2×10?5 M with a correlation coefficient of 0.999. The detection limit was 9.0×10?7 M. The experiment results demonstrated that the modified electrode provided a biocompatible microenvironment for protein and supplied a necessary pathway for its direct electron transfer. 相似文献
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Gabriele K. Wienhausen Larry J. Kricka John E. Hinkley Marlene DeLuca 《Applied biochemistry and biotechnology》1982,7(6):463-473
NADH : FMN oxidoreductase and bacterial luciferase have been efficiently coimmobilized onto Sepharose 4B. This luminescent
immobilized enzyme system can be used to assay NADH. The assay is rapid and sensitive with a lower limit of detection of 0.2
pmol/assay tube. The intra-assay precision was 3.5% at 2 × 10-5
M and 5.8% at 2 × 10-6
M NADH. Light intensity was proportional to NADH concentration from 0.2 to 1000 pmol. Added serum and certain dehydrogenases
were found to be inhibitory; however, inhibition could be eliminated by a combination of heat treatment and dilution.
Firefly luciferase has also been immobilized onto both Sepharose 4B and CL 6B. The detection limit for ATP using this immobilized
enzyme was 0.2 pmol and the assay was linear from 0.2 to 2000 pmol. The intra-assay precision was 4.8% at 2 × 10-4
M and 3.2% at 1 × 10-5
M ATP.
The immobilized enzymes remained fully active when rapidly frozen in the presence of glycerol and DTT. Such preparations could
be stored for at least two months with no loss of activity. A variety of different compounds were used to block any remaining
reactive groups on the Sepharose following immobilization of the enzymes. Glycine, 2-aminoethanol, and ethylenediamine were
examined. The preparations where ethylenediamine was used as a blocking agent exhibited better activity and stability than
the others. 相似文献
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本文研究了熔融制样时熔融温度、熔融时间和脱模剂的加入量对分析结果的影响。研究结果表明,随着熔融温度的升高和熔融时间的加长,分析结果的总值将随之增大。相反,脱模剂量的增加会使分析结果降低。通过对熔融样品时产生的升华物的研究,发现在熔触过程中,四硼酸锂比样品以更大的比例逸出熔融体,从而造成了样品在分析圆片中的相对浓缩。而且在高温熔融时,钾和钠比样品中的其他元素例如硅、铝、铁、钛、钙、镁等更易于逸失。制样条件的不同引起样品和熔剂逸失的比例会有变化,它直接影响测定的结果,这证明了在X射线荧光光谱分析中保持制样条件一致的重要性。 相似文献
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Michael Printz Dr. Clemens Richert Prof. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(14):3390-3402
Effect of a PAH on base pairing : A polycyclic aromatic hydrocarbon (PAH) covalently linked to the N6‐position of a dangling deoxyadenosine residue (see scheme) of an oligonucleotide increases target affinity, but decreases base‐pairing selectivity. Melting point increases of up to 28 °C (14 °C per residue) were observed, and 20 out of 24 mismatch‐containing duplexes are stabilized more strongly by the PAH substituent than their perfectly matched counterpart.
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Dr. Natalia Busto Jesús Valladolid Cristina Aliende Prof. Félix A. Jalón Prof. Blanca R. Manzano Dr. Ana M. Rodríguez Prof. Jorge F. Gaspar Celia Martins Dr. Tarita Biver Dr. Gustavo Espino Prof. José María Leal Prof. Begoña García 《化学:亚洲杂志》2012,7(4):788-801
The reactions of two diaminotriazine ligands 2,4‐diamino‐6‐(2‐pyridyl)‐1,3,5‐triazine (2‐pydaT) and 6‐phenyl‐2,4‐diamino‐1,3,5‐triazine (PhdaT) with ruthenium–arene precursors led to a new family of ruthenium(II) compounds that were spectroscopically characterized. Four of the complexes were cationic, with the general formula [(η6‐arene)Ru(κ2‐N,N‐2‐pydaT)Cl]X (X=BF4, TsO; arene=p‐cymene: 1.BF4 , 1.TsO arene=benzene: 2.BF4 , 2.TsO ). The neutral cyclometalated complex [(η6‐p‐cymene)Ru(κ2‐C,N‐PhdaT*)Cl] ( 3 ) was also isolated. The structures of complexes 2.BF4 and 3.H2O were determined by X‐ray diffraction. Complex 1.BF4 underwent a partial reversible‐aquation process in water. UV/Vis and NMR spectroscopic measurements showed that the reaction was hindered by the addition of NaCl and was pH‐controlled in acidic solution. At pH 7.0 (sodium cacodylate) Ru–Cl complex 1.BF4 was the only species present in solution, even at low ionic strength. However, in alkaline medium (KOH), complex 1.BF4 underwent basic hydrolysis to afford a Ru–OH complex ( 5 ). Fluorimetric studies revealed that the interaction of complex 1.BF4 with DNA was not straightforward; instead, its main features were closely linked to ionic strength and to the [DNA]/complex ratio. The bifunctional complex 1.BF4 was capable of interacting concurrently through both its p‐cymene and 2‐pydaT groups. Cytotoxicity and genotoxicity studies showed that, contrary to the expected behavior, the complex species was biologically inactive; the formation of a Ru–OH complex could be responsible for such behavior. 相似文献
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L ‐Threoninol‐derived acyclic nucleotide monomers were prepared and incorporated into oligonucleotides at preselected positions via phosphoramidite chemistry. Hybridization properties of these modified oligonucleotides with the corresponding natural oligomers were studied, and their vis‐à‐vis comparison with serinol‐modified oligonucleotides was made. Stability of the modified oligomers against nuclease in human serum and snake venom phosphodiesterase (SVPD) was examined. 相似文献
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