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31.
32.
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
33.
《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
34.
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
35.
用循环伏安法研究了染料天青A(AA)与鲱鱼精DNA(dsDNA)在0.20 mol/L pH4.5的HAc-NaAc缓冲溶液中的相互作用。AA在玻碳电极上分别于-0.134 V和-0.082 V(vs.SCE)有一个还原峰和相应的氧化峰。加入dsDNA后,AA的还原峰和氧化峰电流均明显减小,但电子转移系数和电极反应标准速率常数基本不变。AA与dsDNA相互作用生成了一种非电活性的超分子复合物。求得AA与dsDNA复合物的结合比为n(AA)∶n(DNA)=3∶1,结合常数β=2.51×1015。紫外-可见吸收光谱法结果与循环伏安法结果一致。 相似文献
36.
以量化的分子结构参数和实验结果为依据, 运用模式识别技术、多元线性回归和人工神经网络研究了目标分子与DNA相互作用的主要影响因素, 建立了准确性较高的2个键合常数预测模型和1个作用模式预测模型. 初次量化的分子结构参数有21种, 经过筛选发现其中的10种参数对相互作用有显著影响. 研究结果可为抗癌药物的分子设计和筛选提供有价值的信息. 相似文献
37.
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
38.
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
39.
Evanescent fluorobiosensor for the detection of polyaromatic hydrocarbon based on DNA intercalation 总被引:1,自引:0,他引:1
A flow-injection analysis (FIA) system coupled with an evanescent wave (EW) Biosensor employing total internal reflection
of fluorescence radiation (TIRF) for the detection of polyaromatic hydrocarbon that intercalates into DNA is reported. A highly
fluorescent intercalator, “ethidium bromide,” has been used as the reference compound for detection. The EW Biosensor was
developed according to the procedure described earlier (1,2). Data on the analysis of Naphthalene, 3-methy cholanthrene, 7,12-dimethylbenz(a)anthracene,
1,2-benzanthracene, and some standard reference materials supplied by the National Institute of Standards and Technology are
reported. The relative ability of the polyaromatic hydrocarbon to displace ethidium bromide, based on the relative binding
ratio, is found to be on the order of 7,12-dimethylbenz[a]anthracene > 3-methylcholanthrene > 1,2-benzanthracene > napthalene. 相似文献
40.
用循环伏安方法和紫外可见吸收光谱法研究了一种自行合成的Schiff碱配合物与DNA的相互作用,发现此配合物能插入DNA双螺旋结构内部,并得到该配合物与DNA的结合常数。 相似文献