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71.
采用UPLC法测定烟叶中氨基酸的含量。Waters Acquity UPLC BEH C18色谱柱(2.1mm×100mm,1.7μm),AccQ.Tag Ultraa Eluent A及AccQ.Tag Ultraa Eluent B梯度洗脱,流速为0.7mL·min-1,波长:248nm,柱温55℃。18种氨基酸在0.0030-0.204mg/mL范围内有良好的线性关系(r0.9994),平均回收率(n=6)为98.7%。该方法10min内18种氨基酸可完全分离且具有快速、准确、重复性好的特点。 相似文献
72.
本文主要概述了近年来核酸工具酶辅助的基于金属稳定同位素标记的电感耦合等离子体质谱(ICP-MS)检测方法在生物分析中的发展和应用,简要介绍了该方法在蛋白质、核酸及一些生物小分子检测中的应用。最后对核酸工具酶辅助的基于金属稳定同位素标记的电感耦合等离子体质谱(ICP-MS)检测方法的发展前景做了展望。 相似文献
73.
采用稳态吸收和荧光光谱、圆二色谱和皮秒时间分辨荧光光谱手段, 研究了5,10,15,20-四[4-(N-甲基吡啶)]卟啉(TMPyP4)与腺嘌呤(A)、鸟嘌呤(G)、胸腺嘧啶(T)和胞嘧啶(C)等4种碱基, 以及相应的核苷、核苷酸和单链DNA的结合能力和光谱学性质. 研究结果发现, 嘌呤与TMPyP4的结合能力比嘧啶的强. 对于某一碱基系列, 结合能力强弱顺序依次为: 碱基~核苷<核苷酸<单链DNA. 时间分辨荧光谱研究发现, 除鸟嘌呤外, 核酸和TMPyP4复合物的荧光动力学均含有快(1~2 ns)和慢(约10 ns)两个衰减过程, 它们分别是由激基复合体和环境极性对激发态TMPyP4分子的影响所致. 单链DNA能诱导TMPyP4产生诱导圆二色信号, 而单分子(碱基、核苷、核苷酸)则无此功能. 相似文献
74.
Purnanand P. D. Shakya Shefali Saxena M. Sharma Basant Lal 《Phosphorus, sulfur, and silicon and the related elements》2013,188(5):1093-1099
Based on 31 P NMR studies of thionyl chloride reaction with dialkyl alkylphosphonothionates, a method for preparation of alkylphosphonic dichloride has been investigated. A mechanism via intermediacy of ester chloride is suggested. 相似文献
75.
76.
O6-Methylguanosine derivative was treated with sodium nitrite or isoamylnitrite in the presence of carboxylic acid to give the purin-2-yl carboxylate, an unusual product bearing a carboxylic group at the 2-position of the purine moiety. 相似文献
77.
Luís O. de B. Benetoli Henrique de Santana Cássia Thaïs B. V. Zaia Dimas A. M. Zaia 《Monatshefte für Chemie / Chemical Monthly》2008,139(7):753-761
In the present paper, the adsorption of nucleic acid bases (A, adenine; C, cytosine; U, uracil; and T, thymine) on clays (bentonite, kaolinite, and montmorillonite) was studied at different pH (2.00 and 7.20). It should be pointed out there is no reported study of adsorption of nucleic acid bases on clays using seawater
(with the major elements), and a wide range of pH. The main finding of this study was that the ratio of A and T adsorbed on clays ranged from 4.68 to 25.1, much higher than the ratio of their occurrence in organisms ranging from 0.95
to 1.05. The weaker adsorption of U and T on clays raises the question of the possibility of a genetic code based on purines only. The FT-IR spectra at pH 2.00 showed that the interaction of A, C, T, and U with the clays occurs through positively charged, protonated groups.
Correspondence: Dr. Dimas A. M. Zaia, Departamento de Química-CCE, Universidade Estadual de Londrina, 86051-990 Londrina-PR,
Brazil. 相似文献
78.
Antibiotics as inhibitors of nucleic acid and protein synthesis 总被引:2,自引:0,他引:2
G Hartmann W Behr K A Beissner K Honikel A Sippel 《Angewandte Chemie (International ed. in English)》1968,7(9):693-701
The antibiotics of the rifamycin, actinomycin, chromomycin, and anthracycline groups have been found to be specific inhibitors for the DNA-controlled synthesis of RNA in vitro. Streptomycin, chloramphenicol, and puromycin can specifically suppress certain steps in the biosynthesis of proteins. The investigation of the mode of action of such substances may help us to gain a better insight into the transmission of hereditary information. 相似文献
79.
Yuanyuan Ma Tianxiang Chen Muhammad Zubair Iqbal Fang Yang Norbert Hampp Aiguo Wu Liqiang Luo 《Electrophoresis》2019,40(16-17):2011-2028
As a result of their advantages for superparamagnetic properties, good biocompatibility, and high binding capacity, functionalized magnetic materials became widely popular over the past couple of decades, being applied on large scale in various processes of sample preparation for biomedicine. In this work, we perform an in‐depth review on the current progress in the field of magnetic bead separation, discussing in detail the physical basis of this process, various synthesis methods and surface modification strategies. We place special focus of attention as well on the latest applications of magnetic polymer microspheres in cell separation, protein purification, immobilized enzyme, nucleic acid separation, and extraction of bioactive compounds with low molecular weight. Existing problems are highlighted and possible trends of magnetic separation techniques for biomedicine in the future are proposed. 相似文献
80.
Karen Amirbekyan Justine Mansot Keiichiro Ohara Shiraz A. Markarian Jean-Jacques Vasseur Michael Smietana 《Tetrahedron letters》2018,59(3):295-298
Structurally distinct guanidinium derivatives were evaluated for their ability to interact non-covalently with various nucleic acid sequences. Among the evaluated derivatives, 4-[(pyrene-1-ylmethyl)amino]butyl] guanidinium (pbg) was found to demonstrate strong excimer emission upon nucleic acid addition and high levels of discrimination between ds- and ss-DNA. The intensity of excimer emission proved to be dependent on the length of the linker probe as well as the oligonucleotide length and sequence. In particular, G-quadruplex prone structures were found to induce the highest excimer emissions among all nucleic acids tested. 相似文献