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1.
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   

2.
Different from organic solvent, self-assemblies are environment friendly media, and moreover, if they are used as micro-reactor, many meaningful and exciting results may be obtained. In this paper, we investigated the photoisomerization of trans-stilbene in Triton X-100/n-C5H11OH/H2O microemulsions (a kind of self-assemblies) with different compositions and structures to establish the relationship between the reaction yields and the compositions and structures of microemulsions. The results show that the yield of cis-stilbene is increased with the increase of water content or with the decrease of Triton X-100 content, and oil in water (O/W) structure is the best structure for this reaction, which makes it possible to decrease the pollution of environment by organic solvent always used in organic reactions.  相似文献   

3.
Densities, viscosities and tracer diffusion coefficients for solutions of the nonionic surfactants Triton X-45, X-114, X-100 and X-102 in water (except for Triton X-45) and methanol, and for Triton X-100 in three water-methanol mixtures have been measured at 298.15 K and 308.15 K. The activation energy for viscous flow and the contributions to it from solute and solvent have been calculated. Comparison of the Gibbs energies of these systems shows the roles of polyoxyethylene chains of Triton X molecules in the interactions between solute and solvent, and also the effects of solvents on the inter-actions for different solutes. The viscosityB coefficients are positive for all of the surfactant solutions, and the temperature coefficients ofB are negative. In the non-micellar solutions in methanol, values ofB are small and the temperature coefficient ofB is nearly zero. In water-methanol mixtures the critical micelle concentration becomes larger as the methanol content increases up to 40% w/w; micelles are not formed at higher methanol concentrations. TheB coefficient decreases with increasing proportion of methanol in the solvent, and the temperature coefficient ofB changes from a fairly large positive value at low methanol contents to a small negative value at 80% w/w methanol.  相似文献   

4.
Abstract

The diffusion coefficients of Triton X-100 micelles with different shape are determined by cyclic voltammetry without any probe. The first CMC (3.2 × 10?4 mol-Lminus;1) and the second CMC (1.3 × 10minus;3 mol-Lminus;1) of Triton X-100 micelles arc obtained, and the mechanism of electrochemical reaction for Triton X-100 is deduced, When n-hexanol is added, the diffusion coefficient of Triton X-100 micelles with different shape increases, but the solubilization fraction of n-hexanol decreases in spherical micelles and is almost constant in rodlike ones. However, the micropolarity of micelles decreases in both spherical and rodlike micelles. Furthermore, the diffusion coefficient of Triton X-100 micelles with different shape increases with temperature and the diffusion activation energy increases with n-hexanol content.  相似文献   

5.
Recently, we showed that the signal intensity of intact protein by matrix-assisted laser desorption/ionisation (MALDI) mass spectro-metry measurement can be enhanced at least an order of magnitude by the addition of Tween80 to the analyte solution. We did not ascertain whether this effect was limited to Tween80 or if it was more universal of biological detergents. This paper discusses our investigations into this question. A variety of chemically diverse detergents were added to analyte solutions containing bovine serum albumin (BSA) to determine whether there was significant signal enhancement. The addition of Tween20, Tween80, Triton X100 and Triton X-114 improved the attainable sensitivity of intact protein MALDI mass spectrometry compared to spectra acquired without detergent. In some cases there was considerable improvement in signal--for example, with Triton X-100 two charge states (the +1 and +2) of BSA (3.9 fmol) could easily be observed. Another advantage of this process is that the detergent can be added directly to the matrix solution reducing sample handling and preparation time. We propose this phenomenon results from the ability of these detergents to increase the solubility of the protein via hydrophobic and hydrophilic interactions between the detergent and protein. The increased solubility allows for more uniform deposition of the analyte/-matrix mixtures producing an evenly distributed layer of analyte especially useful for data acquisition using an automated laser firing sequence.  相似文献   

6.
Abstract

A technique was developed using silica Sep-Paks to remove Triton X-100 and reduce the concentration of Tween 20 in fatty extracts. Tween 20 concentration was primarily reduced by using non polar solvents to lower solubility. Although each Sep-Pak was capable of adsorbing up to 75 mg of Triton X-100, separation of the detergent from sample extracts was most effective when using sample loads approximately one tenth that size.  相似文献   

7.
Solubility and acid–base properties of calix[4]resorcinarene (H8L) in aqueous solutions of nonionic surfactants Triton X-100, Triton X-405, and Brij-35, as well as isopropanol were studied by pH-potentiometry. The dependence of the amount of a nonionic surfactant necessary to dissolve H8L on the length of ethylene oxide chain was found. The dissociation constants of macrocycle for the first four steps are low sensitive to the medium nature (micellar or water–alcohol solutions). Complexation ability of the [H8 – n L] n anions with respect to tetramethyl- and tetraethylammonium, N-methylpyridinium, and [Co(En)2(C2O4)]+ cations was studied by pH-potentiometry. A noticeable increase in the selectivity of guest–host binding was found on going from aqueous or water–alcohol to micellar solutions.  相似文献   

8.
The kinematic viscosity of binary solutions methanol-n-octane at 293.15-313.15 K and ethanol-n-octane at 263.15-298.15 K in the miscibility range (low concentrations of n-octane) was measured. In the methanol-octane system, the viscosity shows an abnormal behavior. As shown by molecular-dynamic calculations, this effect is due to formation of a specific type of associates, which results in a decrease in the molecular mobility as the n-octane concentration is increased (up to the phase separation point).  相似文献   

9.
Tianqing Liu   《Acta Physico》2008,24(4):625-632
Effects of Triton X-100 on the properties of hemoglobin (Hb) and on the controlled release of ribavirin were studied using the methods of UV-Vis spectrum, fluorescence spectrum, zeta potential, conductivity, high-performance liquid chromatographic (HPLC), and image morphology in Hb/ribavirin/H2O system. With the increase of concentration of Triton X-100 in the system, the intrinsic fluorescence intensity, synchronous fluorescence intensity, fluorescence polarization, zeta potential, and morphology of Hb all changed gradually, and the ribavirin located on the Hb surface was dissociated and released out. When the concentration of Triton X-100 was higher than 1×10−5 mol·L−1, the stronger interaction of Triton X-100 with Hb was predominant. Hb was unfolded and denaturized. A little Triton X-100 can protect Hb from the effects of ribavirin.  相似文献   

10.
Based on the adsorption of Triton X-100 on silica/water and silica/cyclohexane interfaces and the adsorption of Triton X-305 on silica/water interface, two adsorption models have been proposed. On silica/cyclohexane interface, the adsorption of Triton X-100 is monomolecular layer. The molecules in the monolayer are presumed to be attached to the silica surface by their EO chain such that their hydrocarbon chain are exposed to the cyclohexane phase. On silica/water interface, the adsorption of Triton X-100 or Triton X-305 is bimolecular layer. The surfactant molecules orientated in the first layer are similar with that on the silica/cyclohexane interface. The molecules in the second layer are postulated to adsorb on those of the first in the opposite orientation, with EO chain directed toward the adsorption medium. The contact angle of quartz-water-cyclohexane (θW) as a function of the concentration of Triton X-100 and Triton X-305 in water has been measured with quartz plate employing the captive drop (cyclohexane) technique. The observed θW (measured through water) rose from < 10° to a maximum of about 120° for Triton X-100 and of about 40° for Triton X-305 as the concentration of surfactant in water increased, and then fell, as the concentration increased further. The results are consistent with the proposed adsorption models.  相似文献   

11.
Triton X-100/C10H21OH/H2O体系微乳液与溶致液晶   总被引:1,自引:0,他引:1  
关于离子型表面活性剂生成的微乳液与溶致液晶已有不少研究,非离子型表面活性剂生成的微乳液与港致液晶的应用正在引起人们的重视,但由于药物提纯的困难,对其物理化学性质的研究还不多见.本文以非离子表面活性剂TritonX-100/C10H21OH/H2O体系为例,研究了非离子型表面活性剂微乳液和溶致液晶的生成及其结构特性.1实验部分试剂ThitonX-100(Aldrich公司,分析纯)正癸醇(分析纯)、水为一次蒸馏水微乳液区域和层状液晶区域的确定方法及小角x射线衍射测定方法同文献,实验温度20±0.1℃.2结果与讨论2·IThtonX-100、CIOH…  相似文献   

12.
Laser capture microdissection (LCM) technology combined with immunohistochemistry (immuno-LCM) is a valuable tool to obtain specific target cell populations and therefore this technique enables more accurate proteomic profile. In this study, we optimized the regular immuno-LCM technique to isolate and stain pure prolactin cells from either normal human pituitary (n = 6) or prolactioma (n = 11). Compared with the routine procedure, more intense and specific staining could be obtained when sections were pretreated with 0.2% Triton X-100 for 4 min. Interestingly, longer pretreatment (0.2% Triton X-100 for 10 min) or higher concentration (2% Triton X-100 for 4 and 10 min) greatly impaired labeling intensity and cell shape. Further scanning electron microscope study revealed that the component extracted from the cell surface by Triton X-100 was lipid. Using the optimized immuno-LCM technique, more pure prolactin cells could be isolated and prepared for further proteomic analysis. Taken together, we reported an optimized immuno-LCM technique that could effectively dissect pure target cells in different type pituitary adenomas for further proteomics analysis.  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.
The concentration effect of nonionic surfactants (Triton X‐100, Brij 30, Brij 58, Tween 20, and Tween 80) and tert‐butanol was investigated on the Briggs–Rauscher oscillatory reaction in a stirred batch reactor at 25 ± 0.1°C in both the absence and presence of nonionic surfactant and tert‐butanol as well. The addition of Triton X‐100, Brij 58, and Tween 20 influenced the oscillatory parameters in a similar fashion: a decrease of the induction period until its disappearance, an increase of the oscillation period, an increase of the oscillation amplitude, an increase of the duration of the oscillation, and a gradual increase of the oscillation numbers. The addition of Brij 30 has no significant effect on the oscillation parameters of the Briggs‐Rauscher oscillatory reaction. The effect of tert‐butanol on the Briggs–Rauscher oscillatory reaction is very similar to the effect of Brij 58; however, we were unable to observe the disappearance of the induction period on the studied concentration range. The addition of Tween 80 to the reaction mixture has a similar effect as the addition of Triton X‐100, Brij 58, or Tween 20, except for the induction period, which in the case of Tween 80, it becomes larger. The observed effects are explained in terms of micellar catalysis or inhibition, that is, in a different extent of individual reactants of solubilization.  相似文献   

15.
The effect of micelles of different surfactants (cationic, anionic, and neutral) on the kinetics of the glucose oxidase-catalyzed reduction of ferrocenium cations RFc+ (R=H, Bun) byd-glucose was studied by spectrophotometry. In micellar media of Triton X-100 and sodium dodecyl sulfate (SDS), the Michaelis dependence of the reaction rate on the HFc+ concentration is observed, while this dependence has an extreme character in cationic micelles of cetyltrimethylammonium bromide (CTAB). The nature and concentration of surfactants of all types have a slight effect on the rate of reduction of HFc+. The level of enzymatic activity is approximately equal in the case of Triton X-100 and CTAB and is considerably lower in the SDS micelles. On going from HFc+ to BunFc+, the reaction rate is maximum in the cationic CTAB micelles, the anionic SDS micelles exhibit almost no activity, and the activity has an intermediate value in neutral micelles of Triton X-100. The conditions are presented under which the micellar medium controls the catalytic activity of glucose oxidase with respect to ferrocenium cations. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 1795–1801, October, 1997.  相似文献   

16.
In this investigation, the micellization and the clouding phenomena of a nonionic surfactant, poly(ethylene glycol) t-octylphenyl ether (Triton X-100) in the absence and presence of halide ions (sodium salt) electrolytes has been reported. The critical micelle concentration (CMC) of Triton X-100 (in the absence and presence of electrolytes) was measured by surface tension measurements. A decreasing trend of CMC was found with increasing the temperature as well as the concentration of electrolyte. The effectiveness of the halide ions was found in the order: F? > Cl? > Br? > I?. The surface properties of Triton X-100 were evaluated. The thermodynamic parameters of the micellar systems of Triton X-100 were evaluated and from these thermodynamics data, it was found that in the presence of electrolyte the stability of the micellar system is more. The cloud points (CPs) of Triton X-100 were also measured in the absence and presence of halide ions of electrolytes. With the addition of halide ions of sodium salt (electrolyte), a decrease in CP values was observed and the order was found to be: F? > Cl? > Br? > I?.  相似文献   

17.
在氢氧化钡和氢氧化锶水溶液/Triton X-100/环己烷/正己醇四元W/O型反相微乳液中制备了钛酸锶钡纳米棒, 研究了ω0值(水与表面活性剂Triton X-100的物质的量之比)、反应物浓度、陈化时间对产品形貌和尺寸的影响, 用TEM, SAED, SEM, EDS和XRD等技术对产品进行了表征. 结果表明, 所得Ba0.7Sr0.3TiO3纳米棒长约500~1200 nm、直径约为50~120 nm; 具有立方相单晶结构. 产品中钡、锶、钛的物质的量之比约为0.7∶0.3∶1.  相似文献   

18.
Summary The polarographic behaviour of simple solutions of selenite and tellurite in 1M ammonium salts of formate, acetate, tartrate, oxalate, and benzoate solutions in absence and in presence of Triton X-100 as a maximum suppressor and a temperature of 25°C has been investigated. Schemes for the mechanism of reductions occurring at the DME have been deduced. A method for analytical determination of selenite and tellurite in simple solutions as well as in a binary mixture in the presence of 4–14·10–3% Triton X-100 is reported.
Polarigraphisches Verhalten und die Bestimmung von Selenit und Tellurit in einfachen Lösungen oder in binären Mischungen
Zusammenfassung Es wurde das polarographische Verhalten von einfachen Lösungen von Selenit und Tellurit in 1M Ammonsalzlösungen von Formiat, Acetat, Tartrat, Oxalat und Benzoat-Lösungen mit und ohne Triton X-100 als Suppressor bei einer Temperatur von 25°C untersucht. Es wurde ein Reaktionsschema für den Mechanismus der Reduktion an der DME abgeleitet. Eine Methode zur analytischen Bestimmung von Selenit und Tellurit in einfachen Lösungen und in binären Mischungen in Gegenwart von 4–14·10–3% Triton X-100 wird berichtet.
  相似文献   

19.
三嗪染料(Cibacmn blue F3G-A)的蒽醌部分结构类似于腺嘌呤,可以用于亲和分离以NAD+(NADP+)和FAD为辅酶的脱氢酶.三嗪染料通过亲核取代反应修饰曲通X-100,形成的三嗪染料-曲通X-100与成相聚合物吐温80、磷酸钾盐构成液-固亲和萃取体系.从猪心肌匀浆液纯化苹果酸脱氢酶的条件:三嗪染料-曲通...  相似文献   

20.
A series of calcium bilirubinate nanoparticles were synthesized in microemulsions consisting of polyoxyethylene octylphenol ether (Triton X-100), n-hexyl alcohol (n-C6H13OH), cyclohexane (c-C6H12), and an aqueous solution. The particles were characterized by Fourier transform infrared (FT-IR) spectra, powder X-ray diffraction (XRD), inductively coupled plasma atomic emission spectrometry (ICP-AES), transmission electron microscopy (TEM), and zeta potential measurements. The results showed that the initial CaCl2/Na2BR molar ratio and the molar ratio of water to surfactant (ω0) influenced the morphology and microstructure of calcium bilirubinate nanoparticles and the sites of Ca2+ coordination to BR2−. The composition of synthesized calcium bilirubinate was nonstoichiometric. The stability of calcium bilirubinate nanoparticles dispersed in water changes as the Ca2+/BR2− molar ratio and solution pH varied. Dopant Fe2+ ions played a certain role in the simulated mineralization of calcium bilirubinate. A possible mechanism of calcium bilirubinate formation in inverse microemulsions is discussed. The text was submitted by the authors in English.  相似文献   

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