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1.
Russian Journal of Physical Chemistry A - The size and orientation of micelles of nonionic surfactant Triton X-100 in aqueous solutions is determined turbidimetrically. It is shown that micelles...  相似文献   

2.
用等温滴定微量热法测定表面活性离子液体溴化N-十二烷基异喹啉([C12iQuin]Br)与非离子表面活性剂Triton X-100混合物在水溶液中的临界胶束浓度。并以1H核磁共振(NMR)和二维核Overhauser效应增强谱(2D NOESY)研究[C12iQuin]Br与Triton X-100在混合胶束中的作用机理。研究结果显示:混合胶束中,Triton X-100分子的苯环定位于混合胶束的内核,聚氧乙烯链卷曲在异喹啉环周围。本文还应用规则溶液理论和浊点法对比研究了十二烷基三甲基溴化铵(DTAB)-Triton X-100混合胶束体系的相关性质。  相似文献   

3.
The influence of UV-irradiation on the interaction of hemoglobin (Hb) with Triton X-100 is investigated by UV–Vis absorption spectroscopy, fluorescence spectroscopy and freeze-fractured transmission electron microscopy. It is found that in Triton X-100/H2O systems Hb can convert to hemichrome but heme is not present, whereas in Triton X-100/n-C5H11OH/H2O microemulsion Hb can convert to hemichrome and then induce the heme monomer to leave the hydrophobic cavity of Hb. UV-irradiation can also convert Hb to hemichrome, and subsequently make heme to be photodegraded, in which the conversion rate depends on the structure of the surfactant aggregates. Furthermore, in order to understand the mechanism of photostabilization of Hb in Triton X-100 systems, the photostabilization of heme in the Triton X-100 aqueous solutions and Triton X-100/n-C5H11OH/H2O microemulsions has been studied.  相似文献   

4.
Russian Journal of Applied Chemistry - The kinetics of oxygen absorption during the oxidation of methyl linoleate in Triton X-100 micelles has been studied. The order of the reaction with respect...  相似文献   

5.
Norton D  Shamsi SA 《Electrophoresis》2004,25(4-5):586-593
Nonionic surfactants such as Triton X-100 (TX-100) are comprised of a mixture of oligomers with a varying degree of length in the ethoxylate chain. The development of chromatographic methods for resolution of the various oligomers of TX-100 is of environmental importance, and can be useful for quality control and characterization in industrial manufacture. Capillary electrochromatography (CEC) is fast becoming a capable separation technique that combines the benefits of both high-performance liquid chromatography (HPLC) and capillary electrophoresis (CE). This report presents a novel CEC method for separation of the various TX-100 oligomers. A comparison of monomeric vs. polymeric stationary phases for separation of TX-100 was conducted. Since the oligomers of TX-100 were better resolved on a monomeric phase as compared to polymeric phase, a systematic mobile phase tuning was performed utilizing a monomeric CEC-C18-3 microm-100 A stationary phase. Various mobile phase parameters such as acetonitrile (ACN) content, Tris concentration, pH, voltage, and temperature were manipulated in order to achieve the optimum separation of oligomers in less than 30 min.  相似文献   

6.
Semidifferential electroanalysis is used as an effective method for investigating microstructure and structural transition of Triton X-100 microemulsions.  相似文献   

7.
Stabilization of Cu2+ ions in aqueous and aqueous ammonia solutions of copper acetate was studied for a wide range of ammonia concentrations. The structure of copper acetate hydrate complexes was shown to markedly change upon dissolution in water. In aqueous solutions, copper is stabilized as strongly bound Cu2+ associates (dimers) in a distorted octahedral environment composed of water molecules and acetate groups oxygen atoms in equatorial positions with strong exchange interaction via acetate groups. In solutions of copper acetate in aqueous ammonia, the concentration of ammonia has a crucial effect on the ordering of Cu2+ ions in associates. At high ammonia concentration, disordered copper tetra-ammoniate associates with the \({d_{{x^2} - {y^2}}}\) ground state are formed, whereas at low ammonia concentration, bulky Cu2+ ion associate structures are generated, with the \({d_{{x^2} - {y^2}}}\) ground state, hydroxyl groups in the equatorial plane, and water molecules in the axial positions.  相似文献   

8.
The apparent molar volumes, V,2, of glycine, alanine, -amino-n-butyric acid, valine, leucine, and lysine monohydrochloride have been determined in aqueous solutions of 0.05, 0.1, and 0.4 mol-kg–1 Triton X-100 (TX-100), and the partial specific volume, v0, of hen-egg-white lysozyme in 0.4 mol-kg–1 TX-100 by density measurements at 298.15 K. These data have been used to calculate the infinite dilution apparent molar volumes, V2,m0, for the amino acids in aqueous TX-100 solutions and the standard partial molar volumes of transfer, tr V2,m0, of the amino acids from water to the aqueous surfactant solutions. The linear correlation of V2,m0 for a homologous series of amino acids has been utilized to calculate the contribution of the charged end groups (NH3+, COO), CH2 group and other alkyl chains of the amino acids to V2,m0. The results on tr V2,m0, of amino acids from water to aqueous TX-100 solutions have been interpreted in terms of ion–ion, ion–polar, hydrophilic–hydrophilic and hydrophobic–hydrophobic group interactions. For all the six amino acids studied, the values of tr V2,m0 from water to all the studied concentrations of aqueous TX-100 are small in spite of their different hydrophobic content, indicating an overall balance in interactions of zwitterionic/hydrophilic groups of amino acids with the hydrophilic groups of TX-100, and of hydrophobic and ionic/hydrophilic groups of the amino acids with hydrophobic groups of TX-100. Comparison of the interactions of the amino acids with nonionic, anionic and cationic surfactants has also been made and discussed. The partial specific volume of transfer of lysozyme from water to aqueous TX-100 solutions also indicates a balance of the hydrophobic and hydrophilic interactions in the protein–nonionic surfactant system.  相似文献   

9.
Two samples of Triton X-100 (TX100) were compared. The "old sample," manufactured by Rohm and Haas, has a mean degree of ethoxylation of 10.1. The "new sample," manufactured by Union Carbide, has a mean degree of ethoxylation of 9.6. The cmc values near room temperature (23 degrees C, old sample; 24.6 degrees C, new sample), as determined from surface tension measurements, are similar. Dynamic light scattering measurements on the new sample gave hydrodynamic radii at different temperatures in reasonable accord with those reported a number of years ago. In contrast, time-resolved fluorescence quenching (TRFQ) experiments using a pyrene-labeled triglyceride as a probe gave aggregation numbers N(agg) near room temperature that were similar to those determined previously by light scattering; however, the N(agg) of the new sample was larger, and the difference was outside of experimental error to one standard deviation. More troubling was that the TRFQ experiment failed to give meaningful results on solutions exposed to air, as in the case of the older TX100 sample. To get useful data by TRFQ measurements, one had to first remove oxygen from the solution. Copyright 2000 Academic Press.  相似文献   

10.
刘天晴  郭荣 《中国化学》2007,25(4):490-497
The influences of Triton X-100 on hemoglobin (Hb) behaviors were studied by the methods of UV-Vis spectrum, fluorescence spectrum, HPLC, conductivity, zeta potential and negative-staining transmission electron microscope in Hb/acyclovir/Triton X-100/H2O system. With the increase of Triton X-100 concentration in the system, the percentage of the free acyclovir increased from 58%--63% to 90%--94%. The static quenching constant and the association number of acyclovir to Hb decreased. The fluorescence spectrum, conductivity, zeta potential, fluorescence polarization and negative-staining morphology of Hb tended to recover to those of the original state of Hb in the same concentration of Hb. The interaction between Triton X-100 and Hb is stronger than that between acyclovir and Hb. Most Triton-X-100 was associated with Hb at low Triton X-100 concentration. But the interaction of Triton X-100 with Hb was apparently dominant in high Triton X-100 concentration. The Hb structure was unfolded and finally denatured.  相似文献   

11.
抗生素头孢唑酮的加入使得非离子表面活性剂Triton X-100的表面活性降低. 1H-NMR的结果表明,头孢唑酮增溶于胶束极性基团附近.头孢唑酮与Triton X-100胶束的结合常数随Triton X-100含量的增加而下降,但头孢唑酮在Triton X-100胶束相和水连续相之间的分配系数不随Triton X-100含量变化而变化.  相似文献   

12.
表面活性剂在非水溶剂中聚集态的研究所见的报导与水体系相比要少得多.然而近年来对非水体系的研究日益增多.这是因为表面活性剂在非水溶剂中的应用日趋增加,但与水体系相反,对非水体系的性质了解甚少.对表面活性剂非水体系的研究还有助于对其聚集体的共溶剂效应有更深的认识.TritonX-100(以下简写为TX-100)是典型的非离子表面活性剂,在工业上有着广泛的应用.乙二醇在多醇中与水的化学结构最相近问,然而它却是水结构的破坏剂,加入少量的乙二醇会使水的冰点急剧下降.乙二醇又是蛋白质的变性溶剂.表面活性剂在乙二醇中的胶…  相似文献   

13.
Experiments with Triton X-100 as a model surfactant were performed under steadystate conditions, using deoxygenated solutions as well as those saturated with N2O, O2 or N2O/O2 mixtures. The Triton X-100 decomposition yield was dependent on the O2 content of the irradiated system. Oxygen promoted surfactant decomposition in aqueous solution containing only Triton X-100.  相似文献   

14.
Considering surfactant solutions at concentrations exceeding the CMC, another relaxation process besides diffusion occurs, also affecting the dynamic surface tension. The latter equilibration process concerns a micellisation/demicellisation process, representing the disintegration of micelles into monomers. The micellisation kinetics are accounted for by adding a single source term to the diffusion equation of the free monomers.

In the present paper the integration of the diffusion equation is avoided by using the concept of the diffusion penetration depth. Nevertheless, when this approximation is made, good agreement is achieved between experiment and theory for micellar Triton X-100 solutions. Moreover, it follows that diffusion of micelles may not be neglected.  相似文献   


15.
硫胺素—钒(V)—Triton X—100荧光光度法的研究及应用   总被引:4,自引:2,他引:4  
揭念琴  扬景和 《分析化学》1993,21(3):333-335
本文研究了在Trton X-100存在下,琉胺素和钒(Ⅴ)的荧光反应,建立了测定硫胺素的新方法。测定琉胺素的线性范围为2.5×10~(-7)~2.5×10~(-5)mol/L,可用于直接测定生物样品中的硫胺素。  相似文献   

16.
Triton X-100与牛血清白蛋白的相互作用   总被引:37,自引:6,他引:37  
魏晓芳  刘会洲 《分析化学》2000,28(6):699-701
应用荧光光谱法研究了溶液体系中Triton X-100(TX)与牛血清白蛋白(BSA)之间的相互作用。实验表明TX对BSA的荧光有较强的猝灭作用,二者形成不发荧光的复合物所产生的静态猝灭是引起荧光猝灭的主要原因。从荧光猝灭结果求得二者的结合常数,发现在不同TX浓度下,结合常数K及络合个数n均不同;低于TX的cmc,K=440mol/L,n=0.91,高于cmc,K=10mol/L,n=0.42,疏  相似文献   

17.
Property data for tetraalkylammonium cations, [H(CH2) n ]4N+, are reviewed. They pertain to the isolated cations and their transfer from the gas phase into aqueous solutions. Various properties of these cations in aqueous and non-aqueous solutions and data for their transfer between these are also reviewed. Emphasis is placed on the dependence of data on the length n of the alkyl chains rather than on the absolute values. Most of the data are available only for the first four members of the series. The properties of the isolated ions increase linearly with the chain length. Molar enthalpies of formation of the gaseous and aqueous cations, and absolute standard molar enthalpies of hydration, are derived. Standard molar entropies of dissolution of several salts in water are obtained from their solubilities and enthalpies of solution. The molar entropies of the crystalline iodides of the first four members of the series then give the standard partial molar entropies of the aqueous cations and their molar entropies of hydration. The standard partial molar volumes in aqueous and non-aqueous solutions are quite linear with n and in non-aqueous solutions the molar volume hardly depends on the nature of the solvent. On transfer from water to non-aqueous solvents the volume of Me4N+ suffers some shrinkage, that of Et4N+ appears to be unaffected, but from Pr4N+ onwards an increasing expansion takes place. This unexpected result is tentatively explained by hydrophobic intra-molecular association of pairs of alkyl chains in aqueous solutions, resulting in a tightening of the structure. The transfer of the R4N+ cations from water into non-aqueous solvents is governed by a large positive entropy change, outweighing the smaller positive enthalpy change. The transport properties of the aqueous R4N+ cations are non-linear with n. A major impediment to movement is thus the sticking of the water molecules to the ice-like hydrophobic hydration sheaths of the larger cations. The number of water molecules affected by the hydrophobic cations is open to widely differing estimates resulting from various approaches, and constitute an open issue.  相似文献   

18.
The effects of Triton X-100 molecule and micelle on the microstructure and properties of HSA are studied by the some methods of UV spectrum, fluorescence spectrum, fluorescence polarization, circular dichroism, conductivity, and zeta potential. With the increase of Triton X-100 concentration, the UV absorbance, fluorescence intensity of HSA, and the system conductivity all first decrease and then increase. The zeta potential of HSA first goes up and then down. The percents of the β-sheet, random, turn structures, and the polarization of HSA increase but the percent of the α-Helix of HSA decreases. When Triton X-100 concentration is more than 1.0×10−3 mol l−1, the structure parameters change obviously especially for the percents of random and turn structures.  相似文献   

19.
The partitioning of three amino acids, L-phenylalanine, L-tryptophan and L-tyrosine, has been studied in surfactant-based aqueous two-phase systems (ATPS) of Triton X-100 + salts + H2O at 298.15 K. Sodium citrate as an organic salt and magnesium sulfate as an inorganic salt were used to prepare the ATP systems. The effects of tie-line length and salt type on the partitioning of amino acids have been discussed. The results show that the partitioning behavior of the amino acids in the systems containing MgSO4 and Na3C6H5O7 are significantly different, because increasing the tie-line length in MgSO4 solutions leads to a decrease of the partition coefficient, whereas the opposite trend is found in Na3C6H5O7 solutions.  相似文献   

20.
The oxidative coupling reaction of 2,6-dimethylphenol with H2O2 catalyzed by a copper(Ⅱ) Schiff complex in aqueous and Triton X-100 micellar solution under mild conditions was investigated. The kinetics of formation of 3,3′,5,5′-tetramethyl-4,4′-diphenoquinone (DPQ) was studied. Rate constant k2 were obtained. The optimum pH for DPQ generation reaction is 7.25. The main product was DPQ in aqueous buffer solution, but PPE and the oxidized products of PPE remained in Triton X-100 micellar solution.  相似文献   

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