共查询到19条相似文献,搜索用时 109 毫秒
1.
2.
目的为了研究偶氮胂Ⅲ与牛血清白蛋白(BSA)在不同pH条件下(pH=2.0~9.0)的相互作用机理。方法采用荧光光谱法研究偶氮胂Ⅲ对BSA荧光的影响,通过计算获得作用机理的诸多信息。结果偶氮胂Ⅲ对BSA有较强的荧光猝灭作用,猝灭机制为生成复合物的静态猝灭;偶氮胂Ⅲ与BSA间的结合常数在pH 3.0~5.0最大,结合位点数为1;pH=3.5和4.5时偶氮胂Ⅲ与BSA色氨基酸残基间的结合距离在4.10 nm左右;两者主要靠静电引力结合;金属离子Mg2+、Ba2+和Ca2+对两者结合作用有影响。结论偶氮胂Ⅲ及偶氮胂Ⅲ-Ba2+、偶氮胂Ⅲ-Ca2+可作为优良的光谱探针,用于蛋白质的定量测定。 相似文献
3.
4.
5.
在pH 7.40和离子强度0.15 mol/L的模拟生理条件下, 托拉塞米(TOR)对牛血清白蛋白(BSA)的内源荧光产生较强的猝灭作用. 从吸收光谱的变化、温度对猝灭作用的影响及猝灭常数判断该猝灭作用是TOR与BSA形成基态配合物而导致的静态猝灭过程. 文中计算了TOR与BSA的结合常数K、结合位点数n和相关的热力学函数. 在最大猝灭波长342 nm处, 荧光猝灭程度(ΔF)与托拉塞米的浓度成正比, 线性范围和检出限分别为0.02~5.0 mg/mL和6.3 ng/mL. 本文还研究了适宜的反应条件, 考察了共存物质的影响, 表明方法具有较好的选择性, 据此提出了以BSA为探针快速测定痕量TOR的荧光光谱新方法, 适用于服用TOR后尿样和片剂中托拉塞米的测定. 相似文献
6.
运用荧光光谱和紫外吸收光谱研究水溶液中除草醚(NP)与牛血清白蛋白(BSA)的相互作用.结果表明,NP与BSA形成基态复合物导致BSA内源荧光猝灭,猝灭机理主要为静态猝灭和非辐射能量转移.运用位点模型计算298 K、308 K、318 K时结合常数K_A分别为6.97×10~4、5.25×10~4 、4.96×10~4 L·mol~(-1),结合位点数n分别为0.98、0.92、0.96.根据热力学参数确定其作用力以疏水作用和静电作用为主;运用F(o)rster偶极-偶极非辐射能量转移原理,测定了NP与BSA的结合距离r为2.19 nm;用同步荧光技术初步考察了NP对BSA构象的影响. 相似文献
7.
研究了模拟生理条件下,山姜素与牛血清白蛋白(BSA)的相互作用。山姜素猝灭BSA为静态猝灭过程,获得了不同温度下山姜素与BSA的结合常数和结合位点数。考察了Mg2+、Ca2+、Zn2+、Cu2+等金属离子对结合作用的影响。热力学参数研究发现静电作用力为山姜素与BSA的主要结合力。根据Frster非辐射能量转移理论,计算了山姜素与BSA之间的结合距离r0为4.07nm。同步荧光光谱法研究结果表明山姜素对酪氨酸残基的微环境产生了影响,使其疏水性增强,而对色氨酸残基的微环境没有产生影响。 相似文献
8.
9.
10.
采用荧光光谱、紫外光谱对吡柔比星与牛血清白蛋白的相互作用进行了研究。结果表明,吡柔比星和牛血清白蛋白可形成基态配合物导致牛血清白蛋白的内源荧光猝灭,猝灭机理主要为静态猝灭和非辐射能量转移。通过计算获得了二者在不同温度下的结合常数及结合位点数。根据热力学参数判断吡柔比星与牛血清白蛋白之间的作用力主要为范德华力和氢键。根据Frster非辐射能量转移理论确定了吡柔比星和牛血清白蛋白的作用距离。研究了不同金属离子存在下对吡柔比星与牛血清白蛋白结合常数及结合位点数的影响。 相似文献
11.
Spectrometric study of the interaction between Alpinetin and bovine serum albumin using chemometrics approaches 总被引:1,自引:0,他引:1
The binding interaction of Alpinetin (APT) with bovine serum albumin (BSA) was studied by fluorescence, UV-visible and synchronous fluorescence spectroscopy (SFS) under simulated physiological conditions. The measured complex spectra were resolved by multivariate curve resolution-alternating least squares (MCR-ALS), yielding a host of data and information, which otherwise would have been impossible to obtain. The extracted profiles corresponded to the spectra of the single species in the APT/BSA mixture. In addition, the presence of the APT-BSA complex was demonstrated, and it was shown that the associated quenching of the fluorescence from the BSA protein resulted from the formation of APT-BSA complex via a static mechanism. The binding constant (Ka(ave) = 2.34 × 106 L mol−1) and the number of sites (n = 1) were obtained by fluorescence methods as were the thermodynamic parameters (ΔH0, ΔS0 and ΔG0). This work suggested that the principal binding between APT to BSA was facilitated by hydrophobic interactions. The thermodynamic parameters for APT were compared to those from the structurally similar Chrysin and Wogonin molecules. It appeared that the entropy parameters were relatively more affected by the small structural changes. SFS from the interaction of BSA and APT showed that the ligand affected the conformation of BSA. The competitive interaction of APT and site makers with BSA indicated site I as the binding area of APT in BSA. 相似文献
12.
Liu R Yu X Gao W Ji D Yang F Li X Chen J Tao H Huang H Yi P 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2011,78(5):1535-1539
The interaction between salvianic acid A sodium (SAS) and bovine serum albumin (BSA) was investigated using fluorescence and ultraviolet spectroscopy at different temperatures under imitated physiological conditions. The experimental results showed that the fluorescence of BSA was quenched by SAS through a static quenching procedure. The binding constants of SAS with BSA were 2.03, 1.17 and 0.71×10(5) L mol(-1) at 291, 298 and 305 K, respectively. Negative values of ΔG, ΔH, and ΔS indicate that the interaction between SAS and BSA is driven by hydrogen bonds and van der Waals forces. According to F?rster non-radiation energy transfer theory, the binding distance between BSA and SAS was calculated to be about 2.92 nm. The effect of SAS on the conformation of BSA was analyzed using synchronous fluorescence spectroscopy. In addition, the effect of some metal ions Cu(2+), Ca(2+), Mg(2+), and Zn(2+) on the binding constant between SAS and BSA was examined. 相似文献
13.
阿魏酸哌嗪与牛血清白蛋白相互作用的研究 总被引:5,自引:0,他引:5
在模拟人体生理条件下,用常规荧光光谱法和紫外-可见吸收光谱法研究阿魏酸哌嗪和牛血清白蛋白结合反应的特征,并利用同步荧光法和三维荧光法研究了阿魏酸哌嗪与牛血清白蛋白作用前后白蛋白的构象变化.研究表明:阿魏酸哌嗪与牛血清白蛋白形成复合物,从而猝灭牛血清白蛋白的内源性荧光.该过程为静态猝灭过程.根据Stem-Volmer方程求出不同温度下的结合位点数和结合常数;根据Fsmter非辐射能量转移理论可求出其作用距离r=2.33nm:根据基本热力学参数△H、△S和△G判断阿魏酸哌嗪和牛血清白蛋白主要通过氢键和范德华力发生相互作用. 相似文献
14.
15.
16.
17.
运用荧光及紫外-可见吸收光谱法研究了胡椒酸丁二醇单酯(简称BPM)与牛血清白蛋白(BSA)的相互作用。实验结果表明,胡椒酸丁二醇单酯与BSA形成基态复合物导致BSA内源性荧光猝灭,猝灭机理主要为静态猝灭和非辐射能量转移,其猝灭速率常数为Kq为1.077×1013L/(mol.s)(25℃)、0.946×1013L/(mol.s)(37℃)。利用荧光猝灭反应测得结合常数KA为2.6×106(25℃)、3.4×106(37℃),结合位点数n为1.30(25℃)、1.33(37℃)。根据Frster能量转移理论得到结合距离r=2.92nm(25℃)、2.66nm(37℃)和能量转移效率E=0.45(25℃)、0.43(37℃)。通过热力学参数计算,确定胡椒酸丁二醇单酯与BSA的相互作用是熵增加和吉布斯自由能降低的自发过程,主要作用力是疏水作用力。 相似文献
18.
19.
Hui Lin Jingfeng Lan Min Guan Fenling Sheng Haixia Zhang 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2009,73(5):936-941
The mechanism of interaction between mangiferin (MA) and bovine serum albumin (BSA) in aqueous solution was investigated by fluorescence spectra, synchronous fluorescence spectra, absorbance spectra and Fourier transform infrared (FT-IR) spectroscopy. The binding constants and binding sites of MA to BSA at different reaction times were calculated. And the distance between MA and BSA was estimated to be 5.20 nm based on Föster's theory. In addition, synchronous fluorescence and FT-IR measurements revealed that the secondary structures of the protein changed after the interaction of MA with BSA. As a conclusion, the interaction between the anti-diabetes Chinese medicine MA and BSA may provide some significant information for the mechanism of the traditional chinese medicine MA on the protein level to cure diabetes or other diseases. 相似文献