UV-visible and fluorescence spectral study on a pH controlled transfer process of an amphiphilic porphyrin in nonionic micelle

5,15-di(4-hydroxyphenyl)-10,20-di(hexadecyloxyphenyl) porphyrin P was solubilized in nonionic polyoxyethylene(9.5) octylphenol (Triton X-100 or TX-100) micelle solutions. By means of analyzing the UV-visible and fluorescence spectra of the synthesized amphiphilic porphyrin P in different solvent environments, and the relationship between the solubilizing location of the porphyrins in TX-100 micelle and the microenvironment polarity, P is shown to involve in a transfer process for the porphyrin moiety from inner to the outer surface of TX-100 micelle as the pH is increased. The kinetic study of porphyrin incorporate with Cu(II) shows that metalation rate of porphyrin increases with the pH increasing, indicating that metalation rate could be controlled by changing pH.     

Determination of the Micellar Properties of Triton X-100 by Voltammetry Method

ABSTRACT

The diffusion coefficient of the micelle, the first CMC and the second CMC of Triton X-100 are determined by cyclic voltammetry without any probe. The first CMC and the second CMC of Triton X-100 are 3.1x lO^?1 and 1.3× 10^?1 respectively. The viscosity of the micelle solution, the micellar aggregation number and the micellar size increase but the diffusion coefficient decreases with Triton X-100 concentration increasing. The mechanism of the electrochemical reaction of Triton X-100 at platinum electrode is deduced by measurements of conductivity, pH and cyclic voltammetry.     

Transfer of coenzyme Q0 from water to aqueous surfactant solutions: the case of Triton X-100

The effect of UQ0 on the micellization equilibrium of Triton X-100 has been studied by the analysis of the UV absorption spectra of Triton X-100. In the range of the UQ0 concentration investigated, the critical micelle concentration (CMC) increases at increasing of the solute concentration. The dependence of the CMC on UQ0 concentration has been used to calculate the generalized Setchenov constant. Mixing and dilution enthalpies of aqueous solutions of UQ0 and Triton X-100 were measured and used to calculate the enthalpies of transfer of UQ0 from water to Triton X-100 aqueous solutions. From the dependence of the enthalpy of transfer on surfactant concentration, the distribution constant between aqueous and micellar phase and the standard enthalpy of transfer from water to Triton X-100 micelles were evaluated along with the standard transfer free energy and entropy. All measurements were carried out at 298 K.     

Diffusion in surfactant solutions

The diffusion coefficients in water of Triton X-100 and sodium dodecyl sulfate were measured as a function of concentration using the Taylor dispersion technique. For Triton X-100, a nonionic surfactant, the diffusion coefficient drops from 7.4 × 10^-7 cm²/sec at 0.45 g/liter to 6.45 x 10^-7 cm²/sec at 5 g/liter. The diffusion coefficient of methyl yellow solubilized in Triton X-100 is close to that of the surfactant. This behavior is quantitatively consistent with a chemical equilibrium between monomer and micelle. For sodium dodecyl sulfate, an anionic surfactant, the diffusion coefficient increases from 1.76 x 10^-6 cm²/sec at 0.01 M to 4.53 x 10^-6 cm²/sec at 0.125 M. The increase is less when 0.1 M NaCl is added. The diffusion coefficient of the methyl yellow solubilized by the SDS is significantly less than that of the surfactant, particularly at low ionic strength. This behavior can be quantitatively explained by including electrostatic coupling between monomer, micelle, and counterion.     

Properties of Water-Soluble Porphyrin as a Sensitizer in Peroxyoxalate-Hydrogen Peroxide Chemiluminescence System and Its Application to the Quenching FluorometriC Determination of Copper(II)

ABSTRACT

Six kinds of water-soluble porphyrin were examined as a sensitizer (fluorophore) in the bis(2,4,6-trichlorophenyl)oxalate(TCPO)-hydrogen peroxide (H₂O₂) chemiluminescence(CL) system. Among them, coproporphyrin III showed the highest CL intensity. Moreover, the TCPO-H₂O₂-coproporphyrin III CL system was separately examined in each micelle solution using a non-ionic surfactant such as Briji 35 and Triton X-100, and an ionic surfactant such as cetyltrimethylammonium chloride(CTAC) and sodium dodecylsulfate. As a result, the CL intensity along with the coexistence of the CTAC micelle increased approximately 36 times compared to that in the absence of surfactant. Based on these findings, the quenching CL determination of copper(II) was established using the complex formation of coproporphyrin III and copper(II) ion. The calibration graph for the concentration of copper(II) was linear in the range of 2×10^?8M to 1×10^?6M, and the detection limit(3σ) was 1.26×10^?8M. Moreover, the relative standard deviation was 2.9%(10 determinations). The proposed method was applied to the determination of copper(II) ion in waste water and satisfactory results were obtained.     

Factors Influencing Electroanalytical Measurements In Aqueous Surfactant Media

Abstract

Surfactant solutions of sodium dodecyl sulfate (SDS), cetyltrimethylammonium bromide (CTAB) and Triton X-100, have been studied for their utility as media for electroanalytical measurements. Each medium possesses a wide potential window with low background currents within which electrochemical measurements can be conducted. the potential windows at a glassy carbon electrode are +1.2 to -1.6 V for 0.1 M TEAP/SDS, 0.1 M NaCl/0.1 M SDS and 0.1 M NaCl/1.2% Triton X-100, and +0.6 to -1.6 V for 0.1 M NaCl/32 mM CTAB (V vs. Ag/AgCl (3M NaCl)). the M(II/I) redox couples of [ReCdmpe)₃]^2+/+ and [Tc(dmpe)₃]^2+/+ were used as electrochemical probes of each surfactant medium. Results are discussed In terms of the solubilization and interaction of the complexes with the micellar environment. Several factors are described which affect the general shape of the voltammograms as well as the observed values of E^o'; these include (i) the structure of the micelle as influenced by the supporting electrolyte, (ii) the electrostatic affinity of the probe complex for the micellar environment and (iii) the solubilization of each component of the redox couple in the micelle.     

The Micellization and Clouding Phenomena of a Nonionic Surfactant,Poly(ethylene glycol) t-octylphenyl ether (Triton X-100): Effect of (Chloride Salt) Electrolytes

Herein, we report the micellization and the clouding of a nonionic surfactant, poly(ethylene glycol) t-octylphenyl ether (Triton X-100), in aqueous solutions in the absence and presence of (chloride salt) electrolytes. In the absence and presence of electrolytes, the critical micelle concentration (CMC) of Triton X-100 was measured by surface tension measurements. Upon increasing the temperature as well as the concentration of electrolytes, the CMCs decreased. The surface properties and the thermodynamic parameters of the micellar systems were evaluated. From these evaluated thermodynamic parameters, it was found that in the presence of an electrolyte, the stability of the micellar system is high. The cloud points (CPs) of Triton X-100 were also measured in the absence and presence of metallic ions of electrolytes. Upon the addition of metallic ions of chloride salts (electrolytes), the decrease in CP values was observed and the order was found to be: K⁺ > Na⁺ > Li⁺ > NH⁺₄.     

An atomic absorption spectrometric method for the determination of non-ionic surfactants

A method is described for the determination of non-ionic surfactants in the concentration range 0.05–2 mg l^-1.Surfactant molecules are extracted into 1,2-dichlorobenzene as a neutral adduct with potassium tetrathiocyanatozincate(II) and the determination is completed by atomic absorption spectrometry. With a 150-ml water sample, the limit of detection is 0.03 mg l^-1(as Triton X-100).The method requires a single phase separation step, is applicable, without modification, to fresh, estuarine and sea-water samples and is relatively free from interference by anionic surfactants; the presence of up to 5 mg l^-1 of anionic surfactant (as LAS) introduces an error of no more than 0.07 mg l^-1 (as Triton X-100) in the apparent non-ionic surfactant concentration.     

Solution properties of hydrophobically modified acrylamide-based polysulfobetaines in the presence of surfactants

Polymer–surfactant interactions in aqueous solutions of a acrylamide-based, hydrophobically modified polysulfobetaine (ADS) containing 3-[N-(2-methacryloxylethyl)-N,N-dimethylammonio]-propane sulfonate and stearyl methylacrylate, with sodium dodedyl sulfate (SDS), N-dodecyl-N,N,N-trimethylammonium bromide (DTAB), and Triton X-100 were studied using surface tension, rheology, Rayleigh light scattering, and dynamic laser light scattering techniques. The purpose of this study was to highlight the influences of the surfactant structure and the nature of the surfactant head group on the polymer–surfactant interactions. The results show that the interaction and association between ADS and surfactants are distinctly varied depending on surfactant type and surfactant concentration. SDS produced the strongest interactions with ADS, while DTAB and Triton X-100 interact with ADS to a lesser degree, which is attributed to surfactant structure and the nature of the surfactant head group. For SDS and DTAB, there are two driving forces for the complexation of the polymer and surfactants, resulting from the electrostatic interaction and the hydrophobic association. However, for the nonionic surfactant Triton X-100, only hydrophobic association predominated in the interaction between ADS and the surfactant. The mechanism and reconstruction of the polymer–surfactant complexes have been evaluated and discussed.     

Self-Assembly of Dendritic Micellar Structures Based on Triton X-100 and Branched Poly(ethylene oxide)-containing Cyclodextrins

Interaction between the branched poly(etylene oxide)-containing cyclodextrins and nonionic surfactant Triton X-100 was studied. Amphiphilic character of substituted cyclodextrins where poly(etylene oxide) fragments serve as the hydrophilic moiety and outer cyclodextrin surface, as the hydrophobic moiety. Using two groups of experimental methods, it was shown that substituted -cyclodextrin forms inclusion complexes with hydrophilic poly(ethylene oxide) fragment of Triton X-100 molecule, surfactant molecules being incorporated into a micelle composition. The first group of these methods includes viscometry of solutions and measurement of rotational diffusion coefficient, while the other group (tensiometry, gel permeation chromatography, and spectrophotometry) makes it possible to determine colloidal properties of components. The modified micelles consist of nonionic surfactant molecules, whose outer ends are strung with molecules of substituted cyclodextrins; moreover, their structure resembles that of dendrimers due to arising branchings. Note that the self-assembly method was employed to prepare such dendrimers for the first time.     

The Micellization and Clouding of Nonionic Surfactant,Poly(Ethylene Glycol) t-Octylphenyl Ether (Triton X-100): Effect of Halide Ions of (Sodium Salt) Electrolytes

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^?.     

卟啉-噁二唑二元体系光诱导能量及电子传递研究

以5-对氨基苯基-10,15,20-三苯基卟啉及2-苯基-5-(对氨基苯基)-1,3,4-噁二唑为原料合成了系列卟啉-噁二唑二元化合物, 其结构通过¹H NMR, ESI-MS, IR, UV-Vis确定. 对合成化合物进行光谱性能测定, 结果表明, 在卟啉与噁二唑混合体系中, 存在着卟啉激发态分子向噁二唑基态分子的分子间电子传递过程, 导致卟啉激发态的荧光猝灭; 在卟啉-噁二唑二元体系中, 315 nm激发下发生了由激发态噁二唑基团至卟啉基团的能量传递, 导致噁二唑基团荧光猝灭, 卟啉基团荧光增强. 420 nm激发下不存在分子内卟啉基团向噁二唑基团的电子回传竞争; 电化学性能测定进一步表明从噁二唑基团向卟啉基团的电子传递是可能的. 因此卟啉-噁二唑二元化合物可能作为一种模型, 模拟光合作用中电子给体至叶绿素之间的电子传递过程.     

Adsorption of cationic and nonionic surfactants on a SiO<Subscript>2</Subscript> surface from aqueous solutions: 1. Adsorption of dodecylpyridinium bromide and Triton X-100 from individual solutions

Adsorption of cationic surfactant dodecylpyridinium bromide and nonionic surfactant Triton X-100 from aqueous solutions on the surface of SiO₂ particles is studied at various pH values (3.6, 6.5, and 10). The data on the adsorption are compared with the data on the wetting of quartz plates by solutions of these surfactants. Adsorption of both studied surfactants on the SiO₂ surface is greatly dependent on solution pH. The mechanism of adsorption of the cationic surfactant is shown to be changed when passing to the alkaline pH region. Triton X-100 does not demonstrate a substantial change in the adsorption mechanism in the pH range from 3.6 to 10.__________Translated from Kolloidnyi Zhurnal, Vol. 67, No. 2, 2005, pp. 274–280.Original Russian Text Copyright © 2005 by Kharitonova, Ivanova, Summ.     

Tensammetry with accumulation on the hanging mercury drop electrode : Part 3. The behaviour of triton X-100 in mixtures with PEG-9000

The behaviour of Triton X-100, which can be present in monomeric or associated form, and its mixtures with PEG-9000, which does not undergo association, is described. The tensammetric curve of Triton X-100 alone shows one or two peaks at negative potentials, depending on the concentration of Triton X-100, i.e., on the presence of associated forms. For <2 mg l^?1, there is one broad peak, related to monomers of Triton X-100. The calibration plot for this peak is sigmoidal but its rising section (0.05–0.20 mg l^?1) is approximately linear. The calibration curve of the second, much narrower, peak related to associated forms of Triton X-100, grows parabolically with increasing concentration of Triton X-100. The behaviour of a mixture of PEG-9000 with a larger amount of Triton X-100 is similar to the behaviour of a model mixture of components with sufficiently different properties (e.g., PEG 1500/PEG 9000). The peak for PEG-9000, the stronger surfactant, is relatively less affected by a large amount of Triton X-100. Even this effect can be decreased by using a suitable preconcentration potential (?1.45 V vs. SCE) so that PEG-9000 can be determined in the presence of a 1000-fold amount of Triton X-100. Both peaks of Triton X-100 are greatly decreased by the presence of PEG-9000 and the broad peak can be completely suppressed. Triton X-100 cannot be determined accurately in the presence of unknown amounts of PEG-9000.     

Assembly properties of Triton X-100/phosphatidylcholine aggregates during liposome solubilization

The assembly properties of the nonionic surfactant Triton X-100 and phosphatidylcholine (PC) aggregates during the overall solubilization process of PC liposome were investigated. Permeability alterations were detected as a change in 5(6)-carboxyfluorescein (CF) released from the interior of vesicles and bilayer solubilization as a decrease in the static light scattered by liposome suspensions. A direct dependence was established between the bilayer/aqueous phase surfactant partition coefficients (K), the growth of vesicles and the leakage of entrapped CF in the initial interaction steps (surfactant to phospholipid molar ratioRe up to 0.2). These changes may be related to the increasing presence of surfactant molecules in the outer monolayer of vesicles. In theRe range 0.2–0.35 the coexistence of a low vesicle growth with a constant increase of CF release may be correlated with the decrease inK (increased rate of flip-flop of surfactant molecules). Furthermore, in theRe range between 0.64 and 2.0 (lytic levels) almost a linear dependence was detected between the composition of these aggregates (Re) and the decrease in both the surfactant-PC aggregate size and the static light scattered by the system. This dependence was not observed in the last solubilization steps (Re range 2.0–2.60) possibly due to the increased formation of mixed micelles in this interval. The fact that the free Triton X-100 concentration at sublytic and lytic levels showed respectively lower and similar values than its critical micelle concentration confirms that permeability alterations and solubilization were determined respectively by the action of surfactant monomer and by the formation of mixed micelles.Abbreviations PC phosphatidylcholine - PIPES piperazine-1,4 bis(2-ethanesulphonic acid) - T_X-100 Triton X-100 - CF 5(6)-carboxyflucrescein - Re enective surfactant/lipid molar ratio - Re _SAT effective surfactant/lipid molar ratio for bilayer saturation - Re _SOL enective surfactant/lipid molar ratio for bilayer solubilization - S _W surfanctant concentration in the aqueous medium - S _B surfactant concentration in the bilayers - S _T total surfactant concentration - K bilayer/aqueous phase surfactant partition coefficient - K _SAT bilayer/aqneous phase surfactant partition coefficient for bilayer saturation - K _SOL bilayer/aqueous phase surfactant partition coefficient for bilayer solubilization - PL phospholipid - TLC-FID thinlayer chromatography/flame ionization detection system - PI polydispersity index - CMC critical micellar concentration - r ² regression coefficient     

Wetting and adsorption: II. Adsorption of Triton X-100 and Triton X-305 onto carbon black from water and cyclohexane solutions

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.     

Sono-anodic stripping voltammetric determination of cadmium in the presence of surfactant

The effect of applying ultrasound in anodic stripping voltammetry analysis of Cd²⁺ in pH 4.6 buffer containing the surfactant Triton X-100 has been investigated. Manipulation of the horn intensity and the horn/electrode distance was found to reduce the deleterious influence of the surfactant on the height of the cadmium peak. The system has been optimised to take advantage of the in situ cleaning action offered by ultrasound. As a result facile detection of Cd²⁺ (0.05–4 μM) in solutions containing 10 μg/mL Triton X-100 can be achieved without recourse to sample pretreatments or electrode modifications. Received: 17 April 2000 / Revised: 2 June 2000 / /Accepted: 8 June 2000     

Sono-anodic stripping voltammetric determination of cadmium in the presence of surfactant

The effect of applying ultrasound in anodic stripping voltammetry analysis of Cd²⁺ in pH 4.6 buffer containing the surfactant Triton X-100 has been investigated. Manipulation of the horn intensity and the horn/electrode distance was found to reduce the deleterious influence of the surfactant on the height of the cadmium peak. The system has been optimised to take advantage of the in situ cleaning action offered by ultrasound. As a result facile detection of Cd²⁺ (0.05–4 μM) in solutions containing 10 μg/mL Triton X-100 can be achieved without recourse to sample pretreatments or electrode modifications. Received: 17 April 2000 / Revised: 2 June 2000 / /Accepted: 8 June 2000     

Micelle dissociation kinetics study by dynamic surface tension of micellar solutions

The dynamic surface of sodium tetradecylsulphate and sodium bexadecylsulphate solutions in water and also in Triton X-100 solutions was measured by the maximum bubble-pressure method, using modern computerized instrumentation, for a wide range of surface lifetimes (from 0.001 to 10 s), temperatures (from 30 to 80°C) and surfactant concentrations (from 1 to 200 CMC). On the basis of a previously suggested adsorption kinetics theory for micellar solutions of ionogenic surfactants (V.B. Fainerman, Colloids Surfaces, 62 (1992) 333) a method was developed for the calculation of the micellar dissociation rate constant k. For the surfactants studied, k increases with increasing concentration. Moreover, for ionic surfactants the dependence of k on concentration (C) becomes more striking for C> (10–30) CMC. This can be explained by a micelle shape transition and by a strengthening of the intermolecular repulsion in micelles. In solutions of the ionic surfactants the constant k increasing with increasing temperature, whereas in Triton X-100 solutions a temperature dependence is absent. This phenomenon is associated with the different nature of the molecular interactions for ionogenic and non-ionogenic surfactants in micelles. The k values, obtained from results of dynamic surface tension measurements, are in satisfactory agreement with the results of a study of the relaxation of micellar solutions published previously.     

Dynamic surface tension of micellar solutions in the millisecond and submillisecond time range

The analysis of the available bubble life times and dead times for the bubble pressure tensiometer BPA-1S shows that dynamic surface tensions can be measured also for surfactant solutions at concentrations many times higher than the corresponding CMC. For the three nonionic surfactants Triton X-100, Triton X-45, and C14EO8 experiments are performed for solutions with a concentration of up to 200 times the CMC (C14EO8). Comparison of the experimental data with micelle kinetics models yields rate constants for the fast micelle dissolution process, which are in a good agreement with values obtained by other experimental methodologies.