荧光法研究偏钒酸钠与牛血清白蛋白的相互作用

本文用荧光光谱和紫外可见吸收光谱研究了在模拟人体生理条件下，偏钒酸钠与牛血清白蛋白(BSA)结合反应的特征，研究了紫外灯(253.7 nm)照射对偏钒酸钠与BSA结合的影响。紫外吸收光谱显示，加入偏钒酸钠后，牛血清白蛋白的紫外吸收降低，表明偏钒酸钠与BSA形成了缔合物。荧光猝灭光谱显示偏钒酸钠对牛血清白蛋白有较强的荧光猝灭作用，荧光猝灭机理符合静态机制。缔合物的稳定常数分别为：K_s=0.357×10⁴(25 ℃)，K_{s相似文献}   

链状螺旋配位聚合物[Zn(BBP)(p-CPOA)]n的合成及表征

A coordination polymer of [Zn(BBP)(p-CPOA)]_n(where BBP is 2，6-bis(benzimidazolyl)pyridine and p-CPOA is p-carboxylato-phenoxyacetate dianion) has been synthesized and characterized by elemental analysis， IR， TG， and the single crystal structure was determined by X-ray diffraction. The crystal crystallizes in the monoclinic system， space group of P2₁/n with a=1.397 3(4) nm， b=1.138 4(3) nm， c=1.575 9(5) nm， β=91.805(1)°， V=2.505 4(13) nm³， Z=4， D_c=1.513 g·cm^-3， μ=1.030 mm^-1 and F(000)=1 168. Zn(Ⅱ) ion is penta-coordinated and surrounded by two carboxylate O atoms from two different p-CPOA groups in a bis-monodentate mode， three N atoms from the 2，6-bis(benzimidazolyl)pyridine ligand， completing a distorted trigonal bipyramidal coordination configuration. The structure is a helix with a long pitch of 1.138 4 nm. Under direction of supramolecular recognition and attraction， the adjacent chains are formed the double-stranded chain through π-π stacking between the 2，6-bis(benzimidazolyl)pyridine ligands and hydrogen-bonding interactions. A three-dimensional supramolecular network is further constructed through these interactions between the helices. The TG shows that its chain skeleton is thermally stable up to 382 ℃. CCDC: 626650.     

金属-血清蛋白的结构研究 3: Ni^2^+离子诱导的HSA和BSA的缓慢构象变化

用紫外光谱观察到Ni^2^+离子与人或牛血清白蛋白相互作用有显著的滞后效应, 表明Ni^2^+离子的结合可以诱导人或牛血清白蛋白发生从对Ni^2^+离子有较弱亲和力至较强亲和力构象态的缓慢变化(T-R转化); 这一构象变化为试样的旋光能力随时间变化进一步证实;测得并讨论了这一构象变化的速度常数和活化参数; 推测这一构象变化可能主要发生在蛋白质的IA亚区, 并且很可能是一种促使IA亚区变得更加开放的"绞链式运动"。     

共振光散射及平衡透析研究I-与HSA或BSA的结合平衡

首次采用共振光散射、荧光光谱并结合平衡透析法研究了 I- 与人血清白蛋白 ( human serum albumin,简称 HSA)或牛血清白蛋白 ( Bovine Serum Albumin,简称 BSA)结合平衡。首次观测到 I- 对 HSA和 BSA的共振光散射有增强效应 ,却导致 35 0和 70 0 nm处的荧光淬灭。平衡透析的结果表明 :I- 与 HSA或 BSA的结合平衡不适合用 Scatchard模型处理 ,却能较好地符合相平衡分配规律 ,表观相分配常数数量级为 1 0 4。Cl-很可能是通过改变溶液的离子强度影响 I- 的结合。根据不同的 p H条件下的透析结果 ,推测 I- 是与白蛋白上质子化的碱性氨基酸残基结合。     

1,2,4-苯三甲酸铜二维网状配合物的合成及结构表征(英)

在室温下,MnSO₄·H₂O和1,2,4-苯三甲酸(H₃BTC)反应得到化合物[Mn(H₂BTC)₂(H₂O)₄]·2H₂O (1),化合物1和CuSO₄·5H₂O反应得到化合物[Cu(HBTC)(H₂O)_1.5]·H₂O (2)。化合物1是一个单核分子化合物。在化合物1中,每个锰离子和两个H₂BTC^－离子及四个水分子配位。化合物2中,每个铜离子和三个HBTC^2－及两个水分子配位,其中的一个水分子起桥联作用从而形成二维网状结构。     

高氯酸锂-乙酰胺/乙烯脲体系的二元熔盐电解质

制备了高氯酸锂与乙酰胺和乙烯脲形成的二元低温熔盐电解质，采用差示扫描量热法、交流阻抗法和循环伏安法分别对其热学、电化学性质进行了研究.测试结果表明,高氯酸锂-乙酰胺体系具有较好的热稳定性和高的电导性，配比n（LiClO4）:n（Acetamide）=1.0:5.5的样品室温（25 ℃）电导率为1.25×10－3 S•cm－1，80 ℃电导率为1.15×10－2 S•cm－1;其电化学稳定电位窗近3 V左右.     

高电势铁硫蛋白的模型化合物：2，4，6-三苯基苯硫酚的4Fe4S簇合物的合成与性质

新型簇合物(n-Bu₄N)₂［Fe₄S₄(tpbt)₄］(tpbt=2,4,6-三苯基苯硫酚基)通过2，4，6-三苯基苯硫酚和(n-Bu₄N)₂［Fe₄S₄(S-t-Bu)₄］在DMF(二甲基甲酰胺)中进行配体交换反应合成得到。该簇合物在CH相似文献   

之字链聚合物[Zn(o-bda)(phen)(H2O)]n·nH2O的结构

[Zn(o-bda)(phen)(H₂O)]_n·nH₂O (C22H20N2O6Zn) (1) [where o-bda is o-phenylenediacetic acid dianion and phen is 1,10-phenanthroline] crystallizes in triclinic system, space group P1 with a=0.826 5(4) nm, b=1.042 4(5) nm, c=1.238 1(6) nm, α=76.987(9)°, β=70.987(9)°, γ=78.281(8)°, V=0.9728(8) nm³, Z=2, D_c=1.617 g·cm^-3, μ=1.308 mm^-1 and F(000)=488. Zn(Ⅱ) ion has a distorted trigonal bipyramid coordination geometry formed by two carboxyl O atoms from two different o-bda groups, two N atoms from the phen ligand and one terminal water molecule. Adjacent Zn(Ⅱ) ions are interlinked by o-bda groups into a infinite zigzag chain structure with a Zn…Zn distance of 0.825 6(4) nm. The adjacent zigzag chains may also be paired under direction of supramolecular recognition and attraction through both π-π stacking and hydrogen bonding interactions into molecular zippers, which further interlinked into a three-dimensional supramolecular network by these noncovalent interactions. CCDC: 600935.     

Synthesis and Crystal Structure of [H-amp]4[Mo8O26(DMF)2]·2H2O (amp = 2-Amino-6-methyl-pyridine)

The reaction of MoO2(acac)2 with 2-amino-6-methyl-pyridine (amp) in the mixed solvent of DMF (N,N-dimethylformamide) and water affords the title complex [H-amp]4- [Mo8O26(DMF)2]·2H2O which was characterized by elemental analysis, IR spectroscopy and single-crystal X-ray diffraction analysis with the following crystallographic data: C30H54Mo8N10O30, Mr = 1802.35, monoclinic, P21/n, a = 8.631(1), b = 24.260(3), c = 13.351(2)A,β= 104.688(3)°, V = 2704.2(7) A3, Z = 2, Dc = 2.213 g/cm3, μ =1.890 mm－1 and F(000) = 1760. The final R = 0.0281 and Wr = 0.0620 for 4935 observed reflections with I > 2σ(I). X-ray structure analysis has confirmed the existence of γ-[Mo8O26]4－ anion in the molecule. Eight MoO6 distorted octahedra share edges with short terminal Mo-O bonds from 1.691(3) to 1.749(2)A, medium bonds from 1.868(2) to 1.965(2) A And long bonds from 2.059(2) to 2.450(2) A. In the terminal site there exist two DMF ligands bound to the Mo atom through O atoms with the Mo-ODMF bond length of 2.166(3) A, affording a bond strength of 0.433. A three-dimensional network structure was formed through hydrogen bonds.