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1.
运用紫外和荧光光谱研究丁二酰化壳寡糖镧配合物与牛血清白蛋白(BSA)的相互作用.结果表明:随稀土配合物浓度的增加,BSA的紫外光谱表现增色效应并伴有蓝移;稀土配合物可有规律地猝灭BSA的内源荧光,猝灭方式为静态猝灭,并计算了结合常数和结合位点数.  相似文献   

2.
合成并表征了丁二酰化壳寡糖铕配合物,在模拟人体生理条件下,运用紫外和荧光光谱研究了配合物与牛血清白蛋白(BSA)的相互作用.结果表明:随着配合物浓度的增加,BSA的紫外光谱表现出增色效应并伴有蓝移;配合物与BSA形成复合物,从而猝灭BSA内源荧光,该猝灭机制为静态猝灭.计算得到室温下配合物与BSA的结合常数和结合位点数...  相似文献   

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利用元素分析、摩尔电导、红外光谱和紫外光谱,研究了桂皮酸-水杨酸-镍三元配合物的组成和结构.此外,采用紫外光谱、荧光光谱和循环伏安曲线法研究了配合物与牛血清白蛋白(BSA)的相互作用.结果表明:随配合物浓度的增加,BSA的紫外吸收光谱表现增色效应和蓝移;配合物可有规律地猝灭BSA的内源荧光,使BSA发生较强的静态荧光猝灭.在室温下,配合物与BSA的结合常数和结合位点数分别为4.34×105L·mol-1和1.22.  相似文献   

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以Zn()为中心离子,5-氟脲嘧啶(5-Fu)和邻菲口罗啉(Phen)为配体,合成了[Zn(Phen)(5-Fu)2](NO3)2配合物,并利用荧光光谱考察了该配合物与牛血清白蛋白(BSA)的相互作用。实验结果表明,配合物与BSA作用可导致BSA内源荧光猝灭,其猝灭机理为静态猝灭,结合常数Ka=1.56×106L/mol,结合位点数n=1.40,且该配合物能够猝灭BSA分子表面94.0%的色氨酸(Trp)残基,是良好的BSA猝灭剂。  相似文献   

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严赞开  范少萍 《光谱实验室》2010,27(4):1455-1458
运用荧光光谱法研究了几种EGCG金属配合物(EGCG-M)与牛血清白蛋白(BSA)的相互作用。实验结果表明,几种EGCG-M对BSA的荧光光谱有明显猝灭作用,两者之间的相互作用为静态猝灭,并得到了静态猝灭常数、结合常数及结合位点数等数据。  相似文献   

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合成了四种含硫氨基葡萄糖金属配合物(M-GLUS,M=Co, Cu, Ni和Zn),利用元素分析,摩尔电导,核磁共振氢谱进行了结构表征。结果表明含硫配体与这四种二价金属离子均形成了2∶1型非电解质配合物。在pH 7.08 Tris缓冲液中,采用紫外吸收光谱和荧光光谱研究了金属配合物与小牛胸腺DNA的作用机制,发现随着金属配合物量的逐渐增加,DNA电子吸收光谱的最大吸收峰呈增色效应,对配合物DNA-EB体系也能产生荧光猝灭作用,说明四种金属配合物均可与DNA发生相互作用,结合方式为部分插入;在近似生理酸度条件下,利用荧光光谱对金属配合物与HSA/BSA的结合特性进行了初步分析,发现配合物均能猝灭HSA/BSA的荧光强度,利用Scatchard方程计算了四种金属配合物与HSA/BSA的结合常数和结合位点数,表明金属配合物与血清白蛋白有较强的结合且只有1类键合位,其中Co-GLUS与蛋白的结合力最强。  相似文献   

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采用荧光光谱、同步荧光光谱、紫外光谱研究了水溶液中头孢噻肟钠(CTX)与牛血清白蛋白(BSA)之间的相互作用.结果表明:CTX能显著猝灭BSA的内源荧光并以静态猝灭为主;两者以摩尔比1∶1结合,结合常数分别为1.20×104(298K)、7.63×103(308K)和6.69×103(313K)L·mol-1;根据热力学参数判断CTX与BSA之间的作用力主要为氢键和范德华力;依据Foester非辐射能量转移理论计算出CTX与BSA之间的结合距离r为3.26nm,同步荧光光谱研究表明CTX能够使BSA构象发生变化.  相似文献   

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采用荧光光谱研究3-羟基-6-[(4-羧基苯基)偶氮]-苯甲酸(HCPAB)与牛血清蛋白(BSA)的相互作用.通过测定298K和310K下HCPAB与BSA的荧光猝灭光谱,计算得到荧光猝灭常数、反应的结合常数、结合位点数及热力学参数,得出这种荧光猝灭机理符合静态猝灭;由Foerster能量转移机理,计算了当BSA与HCPAB比例为1∶1时分子间距离r=3.18nm和能量转移效率E=0.23,并由同步荧光光谱显示HCPAB与BSA的结合位点更接近于色氨酸.  相似文献   

9.
马钱子碱与牛血清白蛋白相互作用的研究   总被引:4,自引:3,他引:1  
应用荧光光谱和紫外光谱法研究了马钱子碱与牛血清白蛋白(BSA)的结合反应,求得它们之间的结合常数KA和结合位点数n分别为KA=6.3×103,n=0.94(27 ℃);KA=7.7×103,n=0.97(37 ℃)。根据Frster非辐射能量转移理论求出了马钱子碱与BSA之间的结合距离为3.99 nm(27 ℃)和4.21 nm(37 ℃)。探讨了马钱子碱的荧光猝灭机理,结果表明马钱子碱能够插入BSA内部形成基态复合物导致内源荧光猝灭,猝灭机理主要是静态猝灭和非辐射能量转移。根据热力学参数确定马钱子碱与BSA之间的作用力类型主要为疏水性相互作用。  相似文献   

10.
光谱法研究儿茶素与牛血清白蛋白的相互作用   总被引:2,自引:0,他引:2  
运用荧光猝灭光谱、傅里叶红外光谱(FTIR)等光谱手段研究了模拟人体牛理条件下儿茶素与牛血清白蛋白(bovine serum albumin,BSA)的相互作用,求出了儿茶素与BSA结合的结合常数、结合位置、结合类型等参数,并研究了共存离子对儿茶素与BSA的结合常数的影响.实验结果表明:儿茶素与BsA形成复合物从而猝灭BSA的内源荧光,且其荧光猝灭机理符合静态机制.296,303,310 K下儿茶素与BSA结合的结合常数分别为:2.368,2.249,2.152×106 L·mol-1.热力学数据表明儿茶素与BsA主要靠疏水作用力和静电作用力结合,探针实验表明儿茶素与BSA在结合位点Site Ⅰ发生结合.F(o)ster偶极一偶极非辐射能量转移机理确定了儿茶素在BSA中与第214位色氨酸残基之间的距离r=1.93 nm.FTIR光谱显示,儿茶素诱导BSA的二级结构发生了变化.  相似文献   

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为了提高LED光源色温和亮度的调节精度和准确度,结合色温由低向高变化时光色所呈现的渐变特点,提出了一种低色温白光LED灯珠、高色温白光LED灯珠加红绿蓝光LED灯珠补偿式调光的方法.将色温分成三个部分进行调节,每个部分选用不同的LED灯珠组合来进行调光.实验结果表明:不同组合情况下的LED光源的初始输出色温相对于目标值的偏差范围在1%以内;亮度可以在保证色温不变的情况下独立进行调节,初始输出值与目标值的偏差范围在1%以内;经过微调之后可以达到目标值;达到了色温和亮度独立调节的要求;光源发光稳定,不会因为长时间工作而影响调节精度.  相似文献   

13.
The relative stability of alternative carbon nanoparticles with icosahedral symmetry, such as diamond-like nanocrystallites and multiwalled fullerenes (onions), is investigated using the parametric model and the density functional tight-binding (DFTB) method. It is demonstrated that an increase in the size of particles and their hydrogenation favor the stabilization of diamond-like nanocrystallites. The formation of “intermediate” nanostructures consisting of diamond-like nanocrystallites inside the fullerene cage is revealed. The electronic spectra of icosahedral carbon nanoparticles are calculated.  相似文献   

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A technique combining image processing and laser interferometry for visualizing and detecting the deformation of transparent cylindrical and spherical sample is proposed. This deformation includes geometric deformation such as volume transition in profilometry and physical deformation such as refractive index change in tomography. Phase contour lines are used for quantitative analysis and graphical representation of the deformation. This method allows us to visually detect the spatial variation of the deformation field and to evaluate the test quality such as misalignment of optical system. A theoretical analysis using phase contour map to characterize the deformation field is described in detail. A method using phase contour map to qualify the interferometric test is proposed. Analysis of test examples is carried out. Suggestions on using phase contour line method to ameliorate test system design are finally discussed.  相似文献   

16.
We show that good approximations to the exact equivalent local potential (ELP) and damping factor of a nonlocal Perey-Buck potential can be calculated in the partial wave WKB approximation of Horiuchi. The exact ELP and damping factor are obtained by means of a method previously given by one of us. We also confirm that an approximate ELP proposed by Bauhoff et al. is of comparable accuracy as the Horiuchi approximation. Thesel-dependent ELP's exhibit reduced attraction in the interior and provide a test for higher order WKB approximations. We subsequently obtain an equivalent velocity dependent potential (EVDP) which is even exactly wave function equivalent to the original nonlocal potential. This almost local potential, unlike the trivial equivalent local potential, is smooth and well-behaved and is therefore particularly useful in nuclear reactions where the off-shell behaviour of the potential is important.  相似文献   

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Discrepancies and accords between quantum (QM) and classical mechanics (CM) related to expectation values and periods are generally found for both the harmonic oscillator (SHO) and a free particle in a box (FPB), which may apply generally. These indicate non-locality is expected throughout QM. The FPB energy states violate the Correspondence Principle. Previously unexpected accords are found and proven that 〈x 2 CM =〈x 2 QM and τ CM =τ QMb (beat period i.e. beats between the phases for adjoining energy states) for the SHO for all quantum numbers, n. However, for the FPB the beat periods differ at small n. It is shown that a particle’s velocity in an infinite square well varies, no matter how wide the box, nor how far the particle is from the walls. The quantum free particle variances share an indirect commonality with the Aharonov-Bohm and Aharonov-Casher effects in that there is a quantum action in the absence of a force. The concept of an “Expectation Value over a Partial Well Width” is introduced. This paper raises the question as to whether these inconsistencies are undetectable, or can be empirically ascertained. These inherent variances may need to be fixed, or nature is manifestly more non-classical than expected.  相似文献   

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