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1.
Electrostatic interaction between poly(methyl methacrylate) latex particles with different levels of chitosan modification
and bovine serum albumin (BSA) was investigated. The critical flocculation concentration is in the range 5–15 nmol dm−3 for these latex products toward added BSA. A series of isothermal equilibrium adsorption experiments shows that the adsorption
process is divided into two distinct intervals. Adsorption of BSA on latex particles in intervals I and II is primarily controlled
by charge neutralization and hydrophobic interaction, respectively. Intervals I and II can be reasonably described by an empirical
parabola equation and the Langmuir isotherm model, respectively. The maximum amount of BSA adsorbed per unit weight of polymer
particles was observed at pH ≅ 5. A maximum elution yield of about 80% can be achieved using NaSCN as the elution electrolyte,
and NaSCN is more effective in inducing desorption of BSA from the particle surface than NaCl. The chitosan content has very
little effect on the interaction between latex particles and BSA. By contrast, the influence of the content of 2,2′-azobis(2-amidinopropane)
dihydrochloride, a cationic initiator used in preparing the chitosan-modified latex products, on the BSA adsorption process
is significant.
Received: 26 March 1999 Accepted in revised form: 3 June 1999 相似文献
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Jinghua Yu Bo Li Ping Dai Shenguang Ge 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2009,74(1):277-281
The interaction between 3-(4′-methylphenyl)-5-(4′-methyl-2′-sulfophenylazo) rhodanine (M4MRASP) and bovine serum albumin (BSA) was studied by using spectrofluorimetry. It was shown in fluorescence spectrums that the quenching mechanism of BSA by M4MRASP was a static quenching. Meanwhile, the binding constant and binding site numbers were calculated. The action distance (r = 8.03 nm) and energy transfer efficiency (E = 0.12) between donor (BSA) and acceptor (M4MRASP) were obtained according to the theory of Förster non-radiation energy transfer. The effect of M4MRASP on the conformation of BSA was further analyzed by using synchronous fluorescence spectrometry. A new model of the interaction between small organic molecule and biomacromolecule was established. The results offered a reference for the studies on the biological effects and action mechanism of small molecule with protein. 相似文献
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Summary The stability of liposomes (2∶1 egg yolk lecithin:cholesterol, mole ratio; diameter about 100 nm) at increasing bovine serum
albumin (BSA) concentration was study. The influence of introducing positive or negative charge to the liposomal bilayers
was tested. The results indicated appreciable destructive effects of serum albumin on the liposomal membranes of neutral and
negatively charged liposomes. Near-physiological concentration (30 mg mL−1) of albumin dissolved more then 50% of liposomes.
Presented at the 21st ISC held in Stuttgart, Germany, 15th–20th September, 1996 相似文献
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The interaction of magnolol with bovine serum albumin(BSA) was studied using fluorescence spectroscopy under physiological conditions. The binding constants, K, and the ratio of quantum yields of protein fluorescence for complex and free protein, f, at 298 K, 304 K, and 310 K were obtained; the values were 6.799×105 L mol–1, 5.541×105 L mol–1, and 4.344×105 L mol–1 and 0.17, 0.30, and 0.34, respectively. The standard enthalpy change (H°) and the standard entropy change (S°) were calculated to be –28.53 kJ mol–1 and 15.88 J mol–1 K–1, which indicated that hydrophobic forces played major role in the interaction of magnolol and BSA. The binding average distance between magnolol and BSA (4.32 nm) was obtained on the basis of the theory of Förster energy transfer. 相似文献
6.
溴甲酚绿分光光度法测定牛血清白蛋白 总被引:2,自引:0,他引:2
在pH 3.3的Britton-Robinson (B-R)缓冲溶液中, 对溴甲酚绿(BCG)与牛血清白蛋白(BSA)相互作用的吸收光谱进行了初步研究. 结果表明: BCG与BSA作用在室温下能迅速结合成复合物, 并且随着BSA的浓度增大, 在444 nm处的吸收峰降低, 618 nm处吸收峰升高并红移至628 nm. 在此波长下测定其复合物的吸光度, 其吸光度的增加值(ΔA)与BSA的质量浓度在8~260 μg/mL范围内呈良好的线性关系(r=0.9996), 检出限为4 μg/mL. 该方法应用于鲜奶粉和液态纯牛奶样品中总蛋白的测定, 回收率分别为92.7%, 95.5%, 结果与考马斯亮蓝G250法基本一致. 相似文献
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利用荧光技术研究了在生理酸度条件下,二氢氯噻与牛血清白蛋白相互作用,发现二氢氯噻对牛血清白蛋白有较强的荧光猝灭作用,用Stern-Volmer和Line weaver-Burk方程处理荧光猝灭数据,得到了反应的结合常数、结合热力学性质等参数。根据热力学参数确定了该药物与血清白蛋白之间的作用力类型,在此基础上依据福斯特F rster非辐射能量转移理论探讨了二氢氯噻与BSA相互结合时其供体-受体间的距离。与人血清蛋白[1]比较,牛血清白蛋白与二氢氯噻的结合较弱,体现了二氢氯噻与血清蛋白结合的动物间的差异性。同时考察了中药活性成分和金属离子对结合的影响,结果显示甘草次酸对结合的影响较大,提示同时给药时应该注意它们之间的血清药物相互作用。 相似文献
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<正>The interaction mechanism between human serum albumin(HSA) and 1-phenyl-3(fluorenone-2-yl)-5-(9-ethylcarbazole-3-yl)-2- pyrazoline(PFEP) was investigated by fluorescence and absorption titration techniques in combination with molecular modeling method.Stern-Volmer plots at different temperatures proved that PFEP could quench the intrinsic fluorescence of HSA attributed to a static quenching procedure.The association constants were calculated in the range of 1×10~5-8×10~5mol~(-1) at different pH conditions,and the stoichiometric ratio of binding was 1:1 between PEEP and HSA.Molecular modeling study showed that the distance between indole moiety of the Trp214 residue and the carbazole group at the terminal of PFEP was 4.45 A in the optimal model. 相似文献
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In this study, acrylamide–itaconic acid hydrogels containing different amounts of itaconic acid prepared by irradiating with γ radiation are discussed. They have been used in experiments of swelling, diffusion and bovine serum albumin (BSA) adsorption. Maximum and minimum swellings were observed with water (1520%) and BSA (890%), respectively. Diffusion of water, NaCl and BSA within hydrogels were found to be non-Fickian in character. In the experiments of BSA adsorption, type III adsorption was found. The hydrogel prepared with 60 mg itaconic acid and irradiated at 2.00 kGy was found to be the best adsorption system for BSA. The adsorption capacity of acrylamide–itaconic acid hydrogel was found to exceed that of acrylamide hydrogel by more than 80–100%. 相似文献
11.
2, 2′-Dihydroxyazobenzene-based fluorescent system for the colorimetric ‘turn-on’ sensing of cyanide
Jing Wang 《Tetrahedron》2010,66(10):1846-3733
2, 2′-Dihydroxyazobenzene (DHAB) demonstrated high sensitivity and low selectivity toward three anions: CN−, CO32−, and HCO3−. In the presence of Cu(II), complex DHAB-Cu(II) could give rise to enhanced fluorescence intensity by about 45-fold at 590 nm and visible red-to-reddish orange color change upon the addition of cyanide by utilizing an indirect method, while no changes were observed in the presence of other anions, including F−, Cl−, Br−, I−, H2PO4−, CH3COO−, NO3−, CO32− and HCO3−, and SO42−, making the DHAB-Cu(II) complex a selective and sensitive cyanide chemosensor. 相似文献
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Lida Fotouhi Sara Banafsheh Majid M. Heravi 《Bioelectrochemistry (Amsterdam, Netherlands)》2009,77(1):26-30
The electrochemical behavior of the interaction of furazolidone (Fu) with bovine serum albumin (BSA) was investigated by cyclic voltammetry and differential pulse voltammetry at a glassy carbon electrode. Fu shows an irreversible reduction at − 0.34 V in pH 4.0 Britton–Robinson buffer (B–R) buffer–10% DMF solution. After the addition of BSA into the Fu solution, the reductive peak currents decreased without any significant shift of the peak potential and the appearance of new peaks. The electrochemical parameters of the interaction system were calculated in the absence and presence of BSA. This electrochemical method was further applied to the determination of BSA samples and the results were in good agreement with the traditional cellulose acetate electrophoresis. The linear dynamic range was between 10.0 and 80.0 mg l− 1. The detection limit was 7.6 mg l− 1 and the recoveries were obtained from 97.0% to 104.0%. 相似文献
15.
金丝桃苷与牛血清白蛋白相互作用的研究 总被引:1,自引:0,他引:1
采用荧光共振能量转移法研究了金丝桃苷与牛血清白蛋白的相互作用.金丝桃苷对牛血清白蛋白(BSA)的荧光猝灭类型是静态猝灭,25℃时的结合位点数为0.5451.并依据F(o)ster非辐射能量转移理论,研究了给体(牛血清白蛋白)--受体(金丝桃苷)间的结合距离R.和能量转移效率E分别为2.04nm和0.66.同时,采用同步... 相似文献
16.
以电化学方法对秋水仙碱与牛血清白蛋白的相互作用进行了研究。在0.3 mol/L H2SO4底液中,秋水仙碱在玻碳电极上产生一不可逆的氧化峰,峰电位为1.18 V(vs.SCE),加入表面活性剂四丁基氯化铵后,秋水仙碱的峰信号得到明显提高。在上述条件下,加入BSA后秋水仙碱的氧化峰电位正移,峰电流下降,峰电流下降值与BSA加入的浓度在1.5×10-7~2×10-6mol/L(r=0.9978)范围内有良好的线性关系,检出限达4.0×10-8mol/L。进一步探讨了秋水仙碱与BSA的结合数和结合常数,得到结合数为1,结合常数为2.40×105L/mol。 相似文献
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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
18.
Gebrenegus Yohannes Susanne K. Wiedmer Matti Jussila Marja-Liisa Riekkola 《Analytica chimica acta》2010,675(2):191-2561
The use of asymmetrical flow field-flow fractionation (AsFlFFF) in the study of heat-induced aggregation of proteins is demonstrated with bovine serum albumin (BSA) as a model analyte. The hydrodynamic diameter (dh), the molar mass of heat-induced aggregates, and the radius of gyration (Rg) were calculated in order to get more detailed understanding of the conformational changes of BSA upon heating. The hydrodynamic diameter of native BSA at ambient temperature was ∼7 nm. The particle size was relatively stable up to 60 °C; above 63 °C, however, BSA underwent aggregation (growth of hydrodynamic diameter). The hydrodynamic diameters of the aggregated particles, heated to 80 °C, ranged from 15 to 149 nm depending on the BSA concentration, duration of incubation, and the ionic strength of the solvent. Heating of BSA in the presence of sodium dodecyl sulfate (1.7 or 17 mM) did not lead to aggregation. The heat-induced aggregates were characterized in terms of their molar mass and particle size together with their respective distributions with a hyphenated technique consisting of an asymmetrical field-flow fractionation device and a multi-angle light scattering detector and a UV-detector. The carrier solution comprised 8.5 mM phosphate and 150 mM sodium chloride at pH 7.4. The weight-average molar mass (Mw) of native BSA at ambient temperature is 6.6 × 104 g mol−1. Incubation of solutions with BSA concentrations of 1.0 and 2.5 mg mL−1 at 80 °C for 1 h resulted in aggregates with Mw 1.2 × 106 and 1.9 × 106 g mol−1, respectively. The average radius of gyration and the average hydrodynamic radius of the heat-induced aggregate samples were calculated and compared to the values obtained from the size distributions measured by AsFlFFF. For comparison static light scattering measurements were carried out and the corresponding average molar mass distributions of solutions with BSA concentrations of 1.0 and 2.5 mg mL−1 at 80 °C for 1 h gave aggregates with Mw 1.7 × 106 and 3.5 × 106 g mol−1, respectively. 相似文献
19.
Thangaraj Anand Gandhi Sivaraman Murugan Iniya Ayyanar Siva Duraisamy Chellappa 《Analytica chimica acta》2015
Chemosensors based on aminobenzohydrazide Schiff bases bearing pyrene/anthracene as fluorophores have been designed and synthesized for F− ion recognition. The addition of fluoride ions to the receptors causes a dramatically observable colour change from pale yellow to brown/red. 1H NMR studies confirm that the F− ion facilitates its recognition by forming hydrogen bond with hydrogens of amide and amine groups. Moreover these sensors have also been successfully applied to detection of fluoride ion in commercial tooth paste solution. 相似文献
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This article describes the influence of bovine serum albumin (BSA) as an additive on the capillary electrophoresis–potential gradient determination of five quinolones, enoxacin, norfloxacin, ofloxacin, fleroxacin, and pazufloxacin. With 10 mg/L of BSA present in the buffer of 30 mM Tris and 3 mM phosphoric acid at pH 9, the detection limits of the five quinolones were in the range of 0.24–0.68 mg/L, i. e. 5.8–16.5‐fold lower than those obtained with the buffer devoid of BSA, and the analysis time was shortened. We suggest that the inner wall‐adsorbed BSA suppresses the adsorption of quinolones and simultaneously enhances the electroosmotic flow rate. Our experiments indicated that adopting the potential gradient detection technique could eliminate the interference of the UV‐active proteins on the detection of quinolones that would occur with conventional optical detection, and therefore offer high detection sensitivity. As a demonstration, the method was applied to the determination of QNs in fortified chicken muscle sample with satisfactory results. 相似文献