Wetting and adsorption: I. The structure of adsorbed layer of nonionic surfactants at SiO2/water and SiO2/cyclohexane interface

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 (θ_W) 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 θ_W (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.     

Transformation from ordered islands to holes in phase-separating P2VP/PS blend films by adding Triton X-100

Our previous investigation showed that the ordered hexagonal island pattern in the phase-separating polymeric blend films of polystyrene and poly(2-vinylpyridine) (PS/P2VP) formed due to the convection effect by proper control of PS molecular weight, solvent evaporation rate, and the weight ratio of PS to P2VP. In this paper, we further illustrate that, by adding a proper amount of the surfactant Triton X-100 to the PS/P2VP toluene solution, the ordered hexagonal island pattern can be transformed to the ordered honeycomb pattern. The effects of the amount of Triton X-100 on the surface morphology evolution and the pattern transformation are discussed in terms of the collapse of Triton X-100, phase separation between Triton X-100/P2VP and PS, the interfacial interaction between Triton X-100/P2VP and the mica substrate, and the Bénard-Marangoni convection.     

Spectrophotometric and Thermodynamic Studies of Micellar Interaction of Surfactants with p-Nitrophenol

Interaction of p-nitrophenol (NPH) with various surfactants, viz., cetylpyridinium chloride (cationic), sodium dodecylsulphate (anionic) and Triton X-100 (nonionic) are studied spectrophotometrically, in aqueous-micellar medium. The interactions are of electrostatic as well as hydrophobic nature. The strength of interaction is represented in terms of the equilibrium constants and other thermodynamic quantities of formation of the p-nitrophenol-micelle donor-acceptor complexes in addition to a shift in the acid-base equilibrium of NPH. The interaction between NPH and CPC is much stronger that with Triton X-100 whereas the interaction with SDS is very weak. Formation of 1:1 charge transfer (or electron donor-acceptor) complex is evidenced from the results. The interaction of NPH is enthalpy driven with CPC and entropy driven with Triton X-100.     

Inhibition of Triton X-100／n-C5H11OH／H2O System on Hydrolysis of Cephanone

The hydrolysis of cephanone in Triton X-100 micelle and Triton X-100/n-C5H11OH/H2O(O/W) microemulsion were studied by means of UV-Vis absorption spectroscopy. The results show that compared with water, Triton X-100 micelle and Triton X-100/n-C5H11OH/H2O (O/W) microemulsion can inhibit the hydrolysis of cephanone. The inhibition effects of Triton X-100 micelle and Triton X-100/n-C5H11OH/H2O (O/W) microemulsion on the hydrolysis of cephanone are related to the location of cephanone in the interphases of Triton X-100 miceUes and Triton X-100/n-C5H11OH/H2O(O/W) microemulsion droplets.     

Triton X-100对血红蛋白/利巴韦林/H2O体系中血红蛋白性质和药物释放的影响

通过紫外光谱、荧光光谱、zeta电位、电导率、高效液相色谱和影像分析等方法研究了Triton X-100对血红蛋白/利巴韦林/H2O体系中血红蛋白性质和药物控制释放的影响. 研究结果表明, 随着Triton X-100浓度的增大, 荧光强度、荧光偏振、zeta电位和蛋白的形貌均发生较大的变化, Triton X-100能使增溶定位在蛋白表面中的利巴韦林逐渐游离出来. 当Triton X-100浓度大于1×10^-5 mol·L-1 时, Triton X-100 与血红蛋白的作用占主导地位, 血红蛋白开始明显变性. 少量Triton X-100能保护蛋白免受药物的影响.     

Temperature induced phase separation of luminescent silica nanoparticles in Triton X-100 solutions

The aggregation and cloud point behavior of Tb(III)-doped silica nanoparticles has been studied in Triton X-100 (TX-100) solutions at various concentration conditions by fluorimetry, dynamic light scattering, electrophoresis and transmission electron microscopy methods. The temperature responsive behavior of nanoparticles is observed at definite concentration of TX-100, where the aggregation of TX-100 at the silica/water interface is evident from the increased size of the silica nanoparticles. The reversible dehydration of TX-100 aggregates at the silica/water interface should be assumed as the main reason of the temperature induced phase separation of silica nanoparticles. The distribution of nanoparticles between aqueous and surfactant rich phases at the phase separation conditions can be modified by the effect of additives.     

Effects of Triton X-100 on Properties of Hemoglobin and Controlled Release of Drug in Hemoglobin/Ribavirin/H2O System

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.     

非离子表面活性剂层状液晶的结构与增溶作用

相行为研究表明，与ＴｒｉｔｏｎＸ－１００／Ｃ＿６Ｈ＿６／Ｈ＿２Ｏ体系相比，ＴｒｉｔｏｎＸ－１００／Ｃ＿（１０）Ｈ＿（２１）ＯＨ／Ｈ＿２Ｏ体系更易于生成层状液晶，并更为稳定，小角Ｘ－射线衍射表明；ＴｒｉｔｏｎＸ－１００／Ｃ＿（１０）Ｈ＿（２１）ＯＨ／Ｈ＿２Ｏ体系层状液晶中，Ｃ＿（１０）Ｈ＿（２１）ＯＨ与ＴｒｉｔｏｎＸ－１００交替排列于两亲双层中，Ｃ＿（１０）Ｈ＿（２１）ＯＨ／ＴｒｉｔｏｎＸ－１００重量比增加，两亲双层厚度ｄ＿０值不变。以Ｃ＿６Ｈ＿６代替Ｃ＿（１０）Ｈ＿（２１）ＯＨ后，Ｃ＿６Ｈ＿６存在于两亲双层的油层和渗入ＴｒｉｔｏｎＸ－１００分子链尾周围，使得溶剂渗透率减少，并且Ｃ＿６Ｈ＿６／ＴｒｉｔｏｎＸ－１００增加，ｄ＿０值增加。     

表面活性离子液体溴化N-十二烷基异喹啉与非离子表面活性剂Triton X-100在水溶液中的混合胶束

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。     

High-impact polystyrene/halloysite nanocomposites prepared by emulsion polymerization using sodium dodecyl sulfate as surfactant

In this work, we report on the phase behavior of 1-ethyl-3-methyl-imidazolium-ethylsulfate ([emim][etSO(4)])/limonene/polyethylene glycol tert-octylphenyl ether (Triton X-114 or TX-114) microemulsions as a function of ionic liquid (IL) content and temperature. Phase diagrams, conductivity measurements, and small angle X-ray scattering (SAXS) experiments will be presented. A hydrophilic IL, instead of water is used with the goal to enlarge the temperature range on which stable microemulsions can be formed. Indeed, the system shows remarkably large temperature stability, in particular down to -35 °C. We will emphasize on a comparison with a recently published work about microemulsions composed of [emim][etSO(4)], limonene, and Triton X-100 that to some extent are stable at temperatures well below the freezing point of water. The key parameter responsible for the difference in phase behavior, microstructure, and temperature stability is the average repeating number of ethylene oxide units in the surfactant head group, which is smaller for Triton X-114 compared to Triton X-100. Among the fundamental interest, how the amphiphilicity of the surfactant influences the phase diagram and phase behavior of IL-based microemulsions, the exchange of Triton X-100 by Triton X-114 results in one main advantage: along the experimental path the temperature where phase segregation occurs is significantly lowered leading to single phase microemulsions that exist at temperatures beneath 0 °C.     

The Photostabilization of Hemoglobin in Triton X-100 Aqueous Solution and Triton X-100/n-C5H11OH/H2O Microemulsion

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.     

Self-Assembled Supramolecular Micellar Structures Based on Non-ionic Surfactants and Cyclodextrins

The complexation between non-ionic polyethylene oxide (PEO)-based surfactants (Triton X-45, Triton X-100, polyethylene glycol-1000-monostearate, and Brij 35) and cyclodextrins is studied. It is shown that the addition of surfactant solutions to the aqueous solution of alpha, beta-, and gamma-cyclodextrins affords poorly soluble crystalline precipitates. Parameters of crystalline structure and the composition of complexes are analogues to those obtained on the basis of polyethylene oxide. Using a method of surface tension it is shown that cyclodextrins favor the increase of the value of critical micelle concentration (CMC) of surfactants. The dependence of CMC from the molar ratio cyclodextrin/surfactant permits us to determine the composition of inclusion complexes in solution. For Triton X-100 and polyethylene glycol-1000-monostearate values of stoichiometric composition of complexes in solution and in condensed phase agree well. It is shown that in the presence of beta-cyclodextrin the destruction of micelles based on Triton X-100 occurs. UV-spectroscopy is used for the investigation of the microenvironment of a phenyl group in inclusion complexes based on alpha- and beta-cyclodextrins. The interaction of gamma-cyclodextrin with PEO surfactants results in the formation of novel double-tailed surfactants. The values of CMC registered in solutions of these complexes is lower than the corresponding value of Triton X-100 and polyethylene glycol-1000-monostearate. The stoichiometric composition of complexes in solution is established from the dependence of CMC versus the gamma-cyclodextrin/surfactant ratio. The composition of the complexes in solution and condensed phase agree well. The interaction of alpha- and gamma-cyclodextrins with Brij 35 results in the formation of nonstoichiometric complexes. The investigation of the dependences of CMC of modified surfactants from temperature shows that these supramolecular structures exist at high temperatures. Copyright 1999 Academic Press.     

Competitive adsorption in the system: carboxymethylcellulose/surfactant/electrolyte/Al<Subscript>2</Subscript>O<Subscript>3</Subscript>

The adsorption of carboxymethylcellulose (CMC) in the presence or absence of the surfactants: anionic SDS, nonionic Triton X-100 and their mixture SDS/TX-100 from the electrolyte solutions (NaCl, CaCl₂) on the alumina surface (Al₂O₃) was studied. In each measured system the increase of CMC adsorption in the presence of surfactants was observed. This increase was the smallest in the presence of SDS, a bit larger in the presence of Triton X-100 and the largest when the mixture of SDS/Triton X-100 was used. These results are a consequence of formation of complexes between the CMC and the surfactant particles. Moreover, the dependence between the amount of surfactants’ adsorption and the CMC initial concentration was measured. It comes out that the surfactants’ adsorption amount is not dependent on the CMC initial concentration and moreover, it is unchanged in the whole measured concentration range. The influence of kind of electrolyte, its ionic strength as well as pH of a solution on the amount of the CMC adsorption at alumina surface was also measured. The amount of CMC adsorption is larger in the presence of NaCl than in the presence of CaCl₂ as the background electrolyte. It is a result of the complexation reaction between Ca²⁺ ions and the functional groups of CMC belonging to the same macromolecule. As far as the electrolyte ionic strength is concerned the increase of CMC adsorption amount accompanying the increase of electrolyte ionic strength is observed. The reason for that is the ability of electrolyte cations to screen every electrostatic repulsion in the adsorption system. Another observation is that the increase of pH caused the decrease of CMC adsorption. The explanation of this phenomenon is connected with the influence of pH on both dissociation degree of polyelectrolyte and kind and concentration of surface active groups of the adsorbent.     

Cloud point extraction equilibrium of lanthanum(III), europium(III) and lutetium(III) using di(2-ethylhexyl)phosphoric acid and Triton X-100

The cloud point extraction behaviors of lanthanoids(III) (Ln(III) = La(III), Eu(III) and Lu(III)) with and without di(2-ethylhexyl)phosphoric acid (HDEHP) using Triton X-100 were investigated. It was suggested that the extraction of Ln(III) into the surfactant-rich phase without added chelating agent was caused by the impurities contained in Triton X-100. The extraction percentage more than 91% for all Ln(III) metals was obtained using 3.0 × 10⁻⁵ mol dm⁻³ HDEHP and 2.0% (v/v) Triton X-100. From the equilibrium analysis, it was clarified that Ln(III) was extracted as Ln(DEHP)₃ into the surfactant-rich phase. The extraction constant of Ln(III) with HDEHP and 2.0% (v/v) Triton X-100 were also obtained.     

草莓型PMMA/SiO2有机-无机复合微球的合成与表征

在纳米二氧化硅水分散介质中,借助于正离子单体甲基丙烯酰氧乙基三甲基氯化铵(MTC)与未改性纳米二氧化硅颗粒之间的电荷作用,通过MTC与甲基丙烯酸甲酯(MMA)的自由基共聚合,制备了草莓型的PMMA/SiO2复合微球.整个制备反应过程中,纳米二氧化硅无需表面处理,体系中无需另外加入乳化剂或助乳化剂,微球表面吸附的纳米二氧化硅对颗粒起稳定作用.详细讨论了纳米二氧化硅初始添加量、MTC浓度对复合微球的平均粒径、复合微球中二氧化硅含量及微球形态的影响.动态光散射粒度分布仪(DLS)测得复合微球粒径在180~300 nm之间,热重分析(TGA)表明复合微球中二氧化硅含量介于16.4%~40.8%之间.透射电镜(TEM)显示所得复合微球具有草莓型结构,二氧化硅于表面富集.     

水/Triton X-100/正丁醇/环己烷反相微乳液体系中水结构的FT-IR研究

用FT-IR法研究了水/辛烷基苯酚聚氧乙烯醚（Triton X-100）/正丁醇/环己烷组成的反相微乳液体系水池中存在的束缚、结合和自由3种不同的水的状态.分别考察了水与表面活性剂物质的量之比（Rw）、水油比φ（水与环己烷的质量比）、助剂正丁醇的含量对3种状态水含量的影响.发现在φ=2.8、m正丁醇/mTriton X...     

Triton X-100/C10H21OH/H2O体系微乳液与溶致液晶

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…     

L-asparaginase release from Escherichia coli cells with aqueous two-phase micellar systems

A method was proposed to release and separate L-asparaginase (EC 3.5.1.1) from Escherichia coli ATCC 11303 cells with aqueous two-phase micellar systems. The systems were composed of K2HPO4 and Triton X-100. The method combines enzyme release with enzyme purification. The influence of Triton X-100 concentration, K2HPO4 concentration, and pH on the release and partition of L-asparaginase was investigated. Experimental results showed that E. coli cells treated with 9.4% (w/v) K2HPO4 and 15% (w/v) Triton X-100 at 25 degrees C for 15-20 h released nearly 80% of the enzyme. Most of the released enzyme was partitioned to the bottom phase (phosphate-rich phase). The effects of Triton X-100 concentration, K2HPO4 concentration, and pH on cloud point were also studied. Electron micrography indicated that the chemical treatment altered the inner structure of E. coli cells significantly.     

Thermodynamic studies of mixed ionic/nonionic surfactant systems

Mixtures of alkyltrimethylammonium bromide (CnTAB, n=12, 14, 16, 18) and Triton X-100 were studied at a range of mole fractions of ionic surfactant per nonionic surfactant. For each mixture, the cmc obtained from surface tension measurements differed from that obtained using potentiometry. The behavior of these mixed-surfactant systems showed three different regions with increasing total surfactant concentration. From the surface tension and potentiometry data, we obtained the free monomer concentration of ionic surfactant (mi), the micellar mole fraction of surfactant (xi), and the degree of dissociation (alpha) of ionic surfactant. We also obtained the free monomer concentration of Triton X-100 (m2) using PFG-NMR technique. A new equation was introduced to evaluate the activity coefficient in the micellar phase. The excess free energy (GE) and the synergetic parameters of mixtures were determined at various mole fractions of CnTAB/Triton X-100. Finally, the complexity of the synergism parameters was investigated.     

CTAB/n-C5H11OH/H2O体系对青霉素G钾盐水解的抑制作用

微乳液是由表面活性剂、助表面活性剂、水、油等组成的各向同性、低粘度的热力学体系［１］,在生物、环境及其相关领域有着十分重要的应用［２］．近年来,以微乳液为微反应器进行化学反应已引起重视［３－１０］青霉素是一种很重要的抗生素药物,它在阴暗干燥的空气中较...