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991.
A Study of the Probe Effect on the Apparent Image of Biological Atomic Force Microscopy 总被引:1,自引:0,他引:1
Xue Mei WANG * Lei QIN Long BA Zu Hong LU The State Key Lab of Coordination Chemistry Nanjing University Nanjing National Lab of Molecular Biomolecular Electronics Southeast University Nanjing 《中国化学快报》2001,(12)
The atomic force microscopy (AFM) possesses high spatial resolution and it is compatible with liquid environments. AFM can provide possibility to study a wide range of biological problems at the molecular level and acquire topological information at nanometre resolution under physiological conditions1,2. However, a major problem for image reconstruction of biological specimens is that structures of most biological molecules are very soft and delicate, which could be easily deformed and dama… 相似文献
992.
对DNA具有识别和断裂功能的金属插入剂的研究 总被引:6,自引:0,他引:6
本文详尽介绍了国际上对金属配合物与DNA 以插入方式进行识别和反应的前瞻性的工作,为设计能够与特定序列的DNA 进行识别和反应的金属配合物提供了多种策略。 相似文献
993.
IntroductionThe basis of molecular recognition is the expression of information stored in the interact-ing components. In the process of self-assembly, the information is expressed by acomponent's potential for entering into noncovalent relationships with its partners and by itssteric requirements. Thus, it could be expected that suitably designed molecular components...containing proper information would generate self-assemblies with definite architect.re.[1'2J.There have been many examples … 相似文献
994.
IntroductionIn the past decades, chemists have exp1Ored the relatively weak noncovalent interactionsthat could exist between molecules, and also developed the means to design and fabricate.nanostructures serving as candidate for new matefials[1--4]. When these interactions act in acooperative and convergent way, organized assemblies can be constructed by molecular recog-nition directed self-assembly. Many successful nanostructures have been fabricated via suchmethods[5--9]. However, for the a… 相似文献
995.
A novel β-cyclodextrin derivative4 bearing a pyridinio group on the primary side was synthesized by the reaction of 2-aminopyridine with 6-β-cyclodextrin monoaldehyde3, and its complexation stability constants with several aliphatic amino acids have been determined in phosphate buffer solution
( pH = 7.2, 0.1 mol·L−1) at 25 °C by using spectrofluormetric titrations. The stoichiometry is 1:1 for the inclusion complexation of amino acids
with compound4. Circular dichroism study indicates that the aromatic moiety was embedded shallowly into the cyclodextrin cavity. As a spectral
probe, the pyridinio group in the modified cyclodextrin can recognize not only differences of the size and shape of amino
acid molecules, but also theL/D-amino acid chiral isomer. As compared with mono-[6-(1-pyridinio)-6-deoxy]-β-cyclodextrin5, compound4 switched the enantiomer preference forL- toD-isomer, and showed the highest enantioselectivity of 5.4 forD/L-serine. These results are discussed from the viewpoints of geometric compensation, induced-fit concept and cooperation of
several weak interactions. 相似文献
996.
超分子体系中的分子识别桥──连环糊精对模型底物的键合能力及分子选择性 总被引:7,自引:0,他引:7
综述了近年来桥连双环糊精分子识别的研究进展,主要从疏水相互作用、多重识别、尺寸和构型匹配、热力学性质以及环糊精二聚体分子识别的一些应用等方面对研究结果进行了评述. 相似文献
997.
锌卟啉对氨基酸甲酯手性分子识别的理论研究 总被引:5,自引:0,他引:5
用Tripos力场和分子力学方法研究了手笥锌卟啉的最低能量构象,并用分子动力学模拟了锌卟啉对氨基酸甲酯的识别过程,发现锌卟啉与D-氨基酸酯结合能力强于L-氨基酸,这与热力学实验结果一致. 相似文献
998.
Molecular shape equivalence classes defined with respect to equivalence of geometrical and topological properties are represented by logical models. Consequently, the factor space of molecular shapes is provided by a metric useful in shape comparisons. 相似文献
999.
IntroductionAfter the introduction of modified cyclodextrins (CDs) as a new type ofchiral stationaryphases, great progress has been made in enantioselective gas chromatography, which hasraised many questions about the mechanism of chiral recognition and intermolecularinteractionsl. Theoretical computational methods in conjunction with modellingprocedures have been extensively used to investigate the nature of binding processesresponsible for inclusion complex formation2'3. It is of interest t… 相似文献
1000.
药物头孢氨苄分子模板聚合物水中结合性质的研究 总被引:15,自引:0,他引:15
采用分子模板技术合成了以头孢氨苄为模板分子以三氟甲基丙烯酸和4-乙烯基吡啶同时为功能单体的分子模板聚合物。将得到的棒状聚合物研磨过筛后,运用平衡结合实验研究了头孢氨苄分子模板聚合物的结合性质,Scatchard分析表明,在所研究的浓度范围内,在聚合物中形成了两类不同的结合位点。头孢氨苄分子模板聚合物与其化学组成相同的非模板聚合物相比,有很高的结合容量。底物选择性实验表明,与其它结构相似的药物相比, 相似文献