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1.
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   

2.
A near-infrared (near-IR) fluorescence quenching method was developed for the determination of nucleic acids in aqueous solution by using a cationic heptamethylene thiacyanine as a probe. The near-IR cationic cyanine showed maximum excitation and emission wavelengths at 800 and 825 nm, respectively, in the presence of Triton X-100; the fluorescence of the cyanine could be greatly quenched by DNA. The calibration graphs were linear over the range of 10-400 ng/mL for CT (calf thymus) DNA and over the range 5-400 ng/mL for FS (fish sperm) DNA under optimal conditions. The corresponding detection limits were 5.2 ng/mL for CT DNA and 2.5 ng/mL for FS DNA. The relative standard deviation (n = 8) was 3.1% for 75 ng/mL CT DNA and 2.2% for 75 ng/mL FS DNA, respectively. Preliminary research showed that the fluorescence quenching might be ascribed to the formation of dye aggregate facilitated by DNA.  相似文献   

3.
有机酸对非离子型表面活性剂浊点的影响   总被引:1,自引:0,他引:1  
有机酸对非离子表面活性剂TritonX-100浊点的影响与酸的亲水性能、空间效应及其在胶束中的增溶位置有关。直链一元酸的加入均使浊点下降,且酸的碳链越长影响越大。直链二元酸对TritonX-100浊点下降的影响小于直链一元酸,且碳原子数nc<6时,使得浊点略有升高;nc≥6时,使得浊点下降。由于空间位阻作用,支链酸和取代酸使TritonX-100浊点降低幅度较小。  相似文献   

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An experimental study on the electrophoretic mobility (µe) of polystyrene particles after adsorption of Triton X-100 (TX100) is described. Three polystyrene particles with different functionality (sulphate, carboxyl and amidine) were used as solid substrate for the adsorption of the surfactant. The electrophoretic mobility of the polystyrene-TX100 complexes at different electrolyte concentrations has been studied versus the amount of adsorbed surfactant. The presence of TX100 onto the colloidal particles seems to produce a slight shifting of the slipping plane. This is observed for electrolyte concentrations above ~10-3 M. On the other hand, the electrophoretic mobilities of the latex-surfactant complexes with maximum surface coverage were measured versus pH and salt concentration. Specific ion interactions between H+/carboxyl groups and OH-/amidine groups appeared at extreme pH which explain the anomalous electrophoretic behaviour encountered in the region where surface charge change.  相似文献   

6.
Modification of important physicochemical properties of aqueous surfactant solutions can be achieved by addition of environmentally benign room temperature ionic liquids (ILs). While low aqueous solubility of "hydrophobic" ILs limits the amount of IL that may be added to achieve desired changes in the physicochemical properties, hydrophilic ILs do not have such restrictions associated to them. Alterations in the key physicochemical properties of aqueous solutions of a common nonionic surfactant Triton X-100 (TX100) on addition of up to 30 wt % hydrophilic IL 1-butyl-3-methylimidazolium tetrafluoroborate ([bmim][BF4]) are reported. The presence of micellar aggregates in as high as 30 wt % [bmim][BF4]-added aqueous TX100 solutions is established by dynamic light scattering and fluorescence probe behavior. Increasing the concentration of [bmim][BF4] results in decrease in average micellar size and aggregation number and increase in critical micelle concentration, indicating an overall unfavorable aggregation process. Increase in the dipolarity and the microfluidity of the probe cybotactic region within the palisade layer of the micellar phase upon [bmim][BF4] addition implies increased water penetration and the possibility of TX100-[bmim][BF4] interactions. While the changes in some of the physicochemical properties indicate the role of [bmim][BF4] to be similar to a cosurfactant, the IL acts like a cosolvent as far as changes in other properties are concerned. Effectiveness of IL [bmim][BF4] in modifying physicochemical properties of aqueous TX100 is demonstrated.  相似文献   

7.
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   

8.
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   

9.
An experimental desorption study of Triton X-100 from latices with different functionality is presented. Two different strategies to follow the desorption experiment have been used: first, a discontinuous method based on the wash step (centrifugation-removal-redispersion); and second, a continuous method based on the replacement of the disperse media. The desorption results show that in all cases a residual amount of Triton X-100 remains adsorbed, indicating irreversibility of the surfactant adsorption. Finally, the effect of desorption on the colloidal stability of one type of latex-surfactant complex has been analyzed. Copyright 2000 Academic Press.  相似文献   

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Triton X-100-induced inactivation and phosphatidylcholine-induced reactivation of photosystem II (PSII) membranes were investigated using oxygen electrode, variable fluorescence and spectroscopic techniques including absorption and circular dichroism spectroscopy. Incubation of the PSII membrane with Triton X-100 reduced the oxygen-evolving rate, modified the variable chlorophyll fluorescence kinetics, changed the protein secondary structures, altered the chlorophyll binding state to proteins and decreased the excitonic interaction of chlorophyll molecules. Phosphatidylcholine addition did not change the protein secondary structures, but could partially reactivate the reduced oxygen-evolving rate, and partly reversed the variable fluorescence parameters, the chlorophyll binding state and the excitonic interaction of the chlorophyll molecules. The results indicate that the phosphatidylcholine environment can optimize the tertiary structures of PSII.  相似文献   

12.
The molecular motion of a set of n-(9-anthroyloxy) fatty acids (n = 2, 6, 9, 12) solubilized within the non-ionic micelle Triton X-100 has been investigated using fluorescence anisotropy measurements. The anthroyloxy fluorophores occupy a graded series of positions within the micelle and rotational relaxation time data indicate a uniform microviscosity of approximately 215 cP.  相似文献   

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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   

16.
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   

17.
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   

18.
The adsorption isotherms of nonionic surfactants Triton X-100 and Triton X-305 from water and cyclohexane on carbon black have been determined at 15 and 30°C. The Langmuir-type and BET-type isotherms are obtained for adsorption of Triton X-100 and Triton X-305 from water and cyclohexane respectively. Both the contact angles of water for graphite/water/air and graphite/water/cyclohexane decrease monotonously with increasing surfactant concentration. From these results, it is proposed that the adsorption of Triton X-100 and Triton X-305 on carbon black or graphite from water is monolayer. For the adsorption from cyclohexane solutions, the ethyleneoxide group of the surfactant molecules may be adsorbed onto the polar spot at the surface of carbon black, and the hydrophobic group of adsorbed molecules may direct toward the liquid phase or attaches to the nonpolar surface region around the polar spot. As the concentration increases, the ethylene oxide groups of the adsorbed molecules can be aggregated with each other via polar interactions to form hemi-reversed micelle.  相似文献   

19.
Equilibrium interfacial tension measurements at 25.0 °C of the toluene + water system with two widely used surfactants, octylphenol decaethylene glycol ether (Triton X-100) and cetyl trimethyl ammonium bromide (CTAB) having concentrations much lower than their CMC were performed. According to the obtained parameters from the Szyszkowski equation, Triton has higher adsorption tendency than of CTAB. The results obtained for surfactants mixtures are analyzed by the theory of non-ideal interactions in binary mixtures (NIBMs) and the interfacial composition and the interaction parameter in the mixed adsorbed monolayer are determined. The attractive interaction shows a maximum value at nearly equal surfactants bulk mole fraction. The synergism is achieved for Triton bulk mole fractions of 0.30 and higher, and the highest degree of synergism (40.6%) is found for the bulk mole fraction of 0.52 with the lowest investigated constant interfacial tension of 28.0 mN m−1. A correlation was developed for variation of the interaction parameter with bulk mole fraction.  相似文献   

20.
Summary The effect of some surfactants and protective colloids on the absorbance of the iron(III)-phenylfluorone complex has been investigated. The binary complex formed at pH 9.0 show a molar absorptivity of 7.5×104 l · mol–1 · cm–1 at 530 nm. In the presence of 2% Triton X-100, at the same pH, the molar absorptivity of the sensitized complex was 1.19×105 l · mo–1 · cm–1 at 555 nm. Full colour development of the sensitized complex occurred within 25 min and Beer's law was followed up to 0.53 ppm of iron. The molar ratio and continuous variation methods indicated a 13 metal-ligand ratio for the sensitized complex. The effect of various amounts of different ions has been studied under the experimental conditions and some masking agents were recommended. The method has been applied to the determination of iron in copper and nickel metals and some non-ferrous alloys.
Spektralphotometrische Bestimmung von Eisen als Phenylfluoronkomplex sensibilisiert mit Triton X-100
  相似文献   

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