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61.
Cu(phen)22+与6-巯基嘌呤及DNA间的相互作用 总被引:3,自引:0,他引:3
在Tris-NaCl(pH=7.2)缓冲溶液中,应用伏安法、电子吸收光谱分析、溴化乙锭荧光分析、粘度测量和琼脂糖凝胶电泳等技术研究了Cu(phen)2^2+(phen=1,10-邻菲咯啉)与6-巯基嘌呤(6-MP)及DNA间的相互作用。结果表明,Cu(phen)2^2+与6-MP发生了明显的相互作用,其作用产物不仅与小牛胸腺DNA具有更强的相互作用,并且在H2O2和抗坏血酸存在下对质粒pBR322 DNA具有更强的断裂能力,与DNA的作用模式可能为部分插入模式。 相似文献
62.
合成了香兰素缩赖氨酸希夫碱配体(HL)和15种香兰素缩赖氨酸希夫碱的稀土配合物REL(NO3)2.3H2O(RE=Y,La,Ce,Pr,Nd,Sm,Eu,Gd,Tb,Dy,Ho,Er,Tm,Yb,Lu),并通过元素分析、摩尔电导、热重分析、红外光谱、紫外光谱、核磁共振方法对配合物的组成和结构进行了表征。采用紫外光谱和荧光光谱方法初步研究了Nd,Tb,Yb,Lu这4种希夫碱配合物与DNA的相互作用,实验结果显示,随着DNA的加入,配合物在280 nm处的紫外吸收峰不断增强,同时配合物在418 nm左右的荧光发射峰随DNA浓度的增大均逐渐减小,说明配合物和DNA是以静电模式结合。 相似文献
63.
Carbon Nanotubes in Analytical Sciences 总被引:1,自引:0,他引:1
Arben Merkoçi 《Mikrochimica acta》2006,152(3-4):157-174
64.
Jerman S Podgornik A Cankar K Cadet N Skrt M Zel J Raspor P 《Journal of chromatography. A》2005,1065(1):107-113
The availability of sufficient quantities of DNA of adequate quality is crucial in polymerase chain reaction (PCR)-based methods for genetically modified food detection. In this work, the suitability of anion-exchange CIM (Convective Interaction Media; BIA Separations, Ljubljana, Slovenia) monolithic columns for isolation of DNA from food was studied. Maize and its derivates corn meal and thermally pretreated corn meal were chosen as model food. Two commercially available CIM disk columns were tested: DEAE (diethylaminoethyl) and QA (quaternary amine). Preliminary separations were performed with standard solution of salmon DNA at different pH values and different NaCl concentrations in mobile phase. DEAE groups and pH 8 were chosen for further isolations of DNA from a complex matrix-food extract. The quality and quantity of isolated DNA were tested on agarose gel electrophoresis, with UV-scanning spectrophotometry, and by amplification with real-time PCR. DNA isolated in this way was of suitable quality for further PCR analyses. The described method is also applicable for DNA isolation from processed foods with decreased DNA content. Furthermore, it is more effective and less time-consuming in comparison with the existing proposed methods for isolation of DNA from plant-derived foods. 相似文献
65.
《Electroanalysis》2005,17(11):997-1002
Binding reactions of toluidine blue (TB) with herring fish DNA in pH 6.0 Britton–Robinson (B–R) buffer solution have been investigated by cyclic voltammetry and linear‐sweep voltammetry at a glassy carbon electrode. TB has a couple of well‐defined redox peaks. The addition of DNA into the TB solution resulted in the decrease of the redox‐peak currents and the shift negatively of the anodic peak potential. The values of the electrochemical parameters such as the electron number of the electrochemical reaction, the electron transfer coefficient and the electrochemical reaction standard rate constant in the absence and presence of DNA, as well as the values of binding constant and binding ratio of DNA with TB were obtained. Almost unchanged values of the electrochemical parameters in the absence and presence of DNA show that nonelectroactive complexes were formed when TB interacted with DNA. DNA concentration can be determined by the decrease of the peak current of TB. The binding mode of TB with DNA was discussed. 相似文献
66.
Rong‐Min Wang Nai‐Pu He Yu‐Feng He Yun‐Tao Xie Yun‐Pu Wang Eishun Tsuchida 《先进技术聚合物》2005,16(8):638-641
Water‐soluble low molecular weight chitosan of nanometer level and its copper complexes were prepared, and characterized by IR spectra, elemental analysis and gel permeation chromatography (GPC). The modes and mechanism of these copper complexes interaction with DNA were studied by a fluorescent probe method and electrophoresis analysis. It is suggested that there are electrostatic and intercalation modes of copper complexes interacting with DNA. At first, the cationic complex electrostaticly binds to the negatively charged phosphate backbone of DNA, and then a portion of the complex intercalates between the base pairs on the DNA duplex strand. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
67.
把无相移滤波技术引入了分析化学信号处理领域。其方法为:先将输入序列按顺序滤波,然后将所得结果逆转后反向通过滤波器,再将所得结果逆转后输出。通过对色谱信号的实验研究表明,与普通的数字滤波方法相比较,无相移滤波不但具有普通数字滤波的优点,而且不会产生滤波前后的相位偏移,具有良好的应用前景,尤其对于需要准确计算保留时间的场合,用此预处理方法非常适合。 相似文献
68.
基于硫化镉纳米团簇标记DNA电化学传感的研究 总被引:3,自引:2,他引:3
合成了表面具有自由羧基的硫化镉纳米团簇,以乙基-(3-二甲基丙基)碳二 亚胺盐酸盐为偶联活化剂,将其标记于人工合成的5'端氨基修饰的寡聚核苷酸片段 上,制备成CdS纳米团簇标记DNA探针,该寡聚核苷酸片段与大肠杆菌肠毒素基因相 关。在一定的条件下,使基与固定晨玻碳电极表面的待测DNA序列进行杂交反应, 利用阳极溶出示差脉冲伏安法(ASDPV)间接测定Cd的量,实现对互补、非互补 DNA片段的识别和电化学检测,从而对大肠杆菌肠毒素基因片段识别和检测。 相似文献
69.
La-phen-邻苯二甲酸混配化合物与DNA作用的共振光散射光谱及分析应用 总被引:1,自引:0,他引:1
本文研究了镧的混配物LaL1L2·3H2O(L1为邻苯二甲酸,L2为邻菲咯啉)与DNA作用的共振光散射光谱。加入DNA后,在pH6.5~7.5的范围内,LaL1L2·3H2O在DNA分子表面发生长距离自组装,在470nm处产生了增强的共振光散射峰,其发光强度与DNA的浓度成线性关系。该方法的线性范围为23~1870ng·mL-1,检出限(3σ)为23ng·mL-1,可用于测定纳克级的DNA。 相似文献
70.
Two fluorophore-nitrilotriacetic acid conjugates, Pro-Q Sapphire 365 and Pro-Q Sapphire 488 oligohistidine gel stains, have been developed for the fluorescence detection of fusion proteins containing oligohistidine tags directly in sodium dodecyl sulfate polyacrylamide gels, without the requirement for electroblotting, reporter enzymes or secondary detection reagents. Pro-Q Sapphire 365 oligohistidine gel stain exhibits bright-blue fluorescence (emission maximum = 450 nm) when illuminated with UV-A or UV-B light from a standard ultraviolet transilluminator. Pro-Q Sapphire 488 oligohistidine gel stain exhibits bright-green fluorescence (emission maximum = 515 nm) when illuminated with visible light from a laser-based gel scanner equipped with a 470 nm second-harmonic generation (SHG) or 488 nm argon-ion laser source. Typically, 25-65 ng of oligohistidine-tagged fusion protein in whole cell lysates is detectable using either stain. After documenting the fluorescence signal from the Pro-Q Sapphire dyes, gels may be post-stained with the red-fluorescent SYPRO Ruby protein gel stain in order to reveal the total protein pattern. 相似文献