Micelle Concentration Of Nonionic Surfactants Research Articles

P‐toluenesulfonychloride‐based niosomes for Amphotericin‐B against Leishmaniasis

AbstractNonionic‐surfactants have been reported as nanocarriers for delivering low bioavailable drugs at the target sites. In the current study, two new nonionic surfactants were synthesized to enhance the oral bioavailability of the low water‐soluble antifungal drug Amphotericin‐B. The hemolysis effect of nonionic surfactants on red blood cells and cytotoxicity against the 3T3 cell line was studied. Both surfactants have shown low hemolysis and cytotoxicity as compared to standard Tween 80. The morphology of drug‐loaded niosomes of nonionic surfactants 1 and 2 was studied by using atomic force microscopy (AFM), and both surfactants based vesicles were spherical, while their average sizes were measured by dynamic light scattering (DLS). The average size, zeta potential and polydispersity index (PDI) values of surfactants 1 and 2 were 282 ± 3 nm, −8 ± 1 mV, 0.26 and 287 ± 3 nm, −10 ± 1 mV, 0.24. The drug entrapment efficiency and critical micelle concentrations of nonionic surfactants were determined by using UV–visible spectroscopy. The structures of surfactants 1 and 2 were assessed through single‐crystal x‐ray crystallographic analysis, while Hirshfeld analysis was performed to study the intermolecular interactions of molecules, as well as the packing behavior of their crystals. The nonionic‐surfactant 1 was further tested for antileishmanial activity against Leishmania tropica promastigotes, in both drug‐loaded and unloaded niosomal vesicular forms. The nonionic surfactant 1 was found to be a potentanti‐leishmanial agent in the drug‐loaded form with IC50 = 3.02 ± 0.91 μM in comparison to their standard drugs Amphotericin‐B (IC50 = 3.8 ± 0.04 μM) and miltefosine (IC50 = 42.2 ± 0.6 μM) (p < 0.1). These results, therefore, form the basis of further results towards efficient drug delivery against tropical disease Leishmaniasis.

Prediction of the Critical Micelle Concentration of Nonionic Surfactants by Dissipative Particle Dynamics Simulations.

Micellization of surfactant solutions is a ubiquitous phenomenon in natural systems and technological processes, and its theoretical description represents one of the cornerstone problems in the physical chemistry of colloidal systems. However, successful attempts of quantitative modeling confirmed by experimental data remains limited. We show, for the first time, that the dissipative particle dynamics with rigorously defined soft repulsion interaction and rigidity parameters is capable of predicting micellar self-assembly of nonionic surfactants. This is achieved due to a novel approach suggested for defining the interaction parameters by fitting to the infinite dilution activity coefficients of binary solutions formed by reference compounds that represent coarse-grained fragments of surfactant molecules. Using this new parametrization scheme, we obtained quantitative agreement with the experimental critical micelle concentration and aggregation number for several typical surfactants of different chemical structures. The proposed approach can be extended to various colloidal and polymeric systems beyond nonionic surfactant solutions.

Indication of critical micelle concentration of nonionic surfactants with large emission change using water-soluble conjugated polymer as molecular light switch

A new near-infrared water-soluble conjugated polymer, i.e. poly [2,5-di (propyloxysulfonate)-1,4-phenylene-ethynylene-9,10-anthrylene] (PPEASO3) was synthesized to investigate its interaction with surfactants. It was found that PPEASO3 has only a weak fluorescence emission at about 670nm due to its self-aggregation in water and in aqueous solution containing a low concentration of nonionic surfactants, i.e. below their critical micelle concentration (CMC). However, a dramatic fluorescence enhancement with a large emission blue-shift (>40nm) was found once the concentration of nonionic surfactants reached the CMC (especially for Triton X-100). An orange fluorescence could be observed even with naked-eyes under UV-lamp, which gave a direct indication for the micelle forming process and provided a simple method for the CMC determination of the nonionic surfactants. The CMC values determined by this method were in good agreement with those obtained by other techniques. The dramatic emission change observed could be ascribed to the intensive hydrophobic interaction between PPEASO3 and surfactants micelle, which greatly disrupts the aggregation of the polymer and increase the fluorescence efficiency of PPEASO3.

QSPR with extended topochemical atom (ETA) indices: Modeling of critical micelle concentration of non-ionic surfactants

In this present study, we have developed predictive quantitative structure–property relationship (QSPR) models with extended topochemical atom (ETA) indices for critical micelle concentration (logCMC) values of 54 non-ionic surfactants. The ETA descriptors have been developed by the present authors’ group and these can be easily calculated from 2D representation of chemical structure without requirement of conformational analysis and alignment steps. Different chemometric tools such as stepwise multiple linear regression (MLR), genetic function approximation (GFA) and partial least squares (PLS) were employed in this study for development of the models. The final PLS models were found to be well validated internally, externally and also by the overall validation technique. From the results, it is clear that the best ETA model shows reliable prediction of the logCMC values and the statistical quality of the model is comparable with the corresponding non-ETA model. It is also observed that the use of ETA descriptors along with the non-ETA ones improved the statistical quality of the models. Thus, it can be inferred that the ETA indices encode important chemical information regarding not only the topological attributes, but also the effect of electronegativity, molecular volume, branching, shape parameter and nature of atoms and bonds, etc. Hence, the ETA descriptors can be satisfactorily employed for modeling the CMC values of non-ionic surfactants.

Prediction of Critical Micelle Concentration of Nonionic Surfactants by a Quantitative Structure – Property Relationship

A quantitative structure - property relationship (QSPR) was used to predict the critical micelle concentration (cmc) of nonionic surfactants. The relation was developed for a diverse set of 23 nonionic surfactants (r = 0.99, F-test = 1042.5) employing the connectivity and valence connectivity indices only. The molecular connectivity indices were calculated for the whole molecule which was a simple and general approach.

QSPR for Nonionic Surfactants

A quantitative structure property relationship; QSPR was preformed as a means to predict critical micelle concentration of nonionic surfactants via correlating properties to parameters calculated from molecular structure. Such parameters; molecular weight, M w , hydrophobic‐hydrophilic fragments molecular weight ratio, χ, polarizability, α, partition coefficient, log P, energy of hydration, EH, Van der Waal's surface area, Γ, and dipole moment,μ. Principal component analysis PCA and multiple linear regression technique MLR were performed to examine the relationship between multiple variables of the above parameters and the critical micelle concentration of nonionic surfactants. The results of PCA explain the inter‐relationships between log cmc and different variables. The linear relationship between the selected parameters and the critical micelle concentration was modeled according to the better statistical results. The best regressed model has highest coefficient of determination (R2=0.9889), highest statistical significance (F=391.599), and lowest standard errors (s2=0.2358). The obtained a QSPR model allows estimating of critical micelle concentration for nonionic surfactants using theoretical‐calculated descriptors.

Effectiveness of Surface Tension Reduction by Nonionic Surfactants with Quantitative Structure‐Property Relationship Approach

Quantitative structure‐property relationship (QSPR) study was made for the prediction of surface tension at the critical micelle concentration of nonionic surfactants (γ0) in aqueous solution with the quantum chemistry method. The optimum regressed model simply includes three descriptors: a constitutional descriptor, the number of oxygen atoms of the hydrophilic segment (NO); a topological descriptor, the Kier and Hall index of zero order (KH0) of the hydrophobic segment; and a quantum chemical descriptor, the heat of formation (ΔH f ) of a mole of surfactant molecules. The established general QSPR between γ0 and the descriptors produces a correlation coefficient of multiple determination, R 2=0.9942, for 30 studied nonionic surfactants.

Quantitative structure-property relationships of surfactants: prediction of the critical micelle concentration of nonionic surfactants

The quantitative structure–property relationship was used to predict the critical micelle concentration (cmc) of a nonionic surfactant in aqueous solution. Several structural, electronic, spatial and thermodynamic properties were selected as descriptors to build the relationship between the macroscopic properties (such as the cmc) and microscopic structures. These descriptors include the octanol/water partition coefficient, the heat of formation, the volume of a molecule and the energy of the lowest unoccupied molecular orbital. A general four-parameter structure–property relationship between the logarithm of the cmc and the descriptors, which was developed for a set of 37 nonionic surfactants (r2=0.990, F-test=802.970), can be used to predict the cmc of nonionic surfactants without the experimental data. The success of this approach indicates that the prediction of the cmc for other surfactants, such as anionic, cationic and zwitterionic surfactants, as well as the prediction of other surfactant properties, can be obtained.

A quantitative structure-property relationship study for the prediction of critical micelle concentration of nonionic surfactants

A quantitative structure-property relationship (QSPR) study was carried out for the prediction of the critical micelle concentration ( cmc) of nonionic surfactants in aqueous solution. The regressed model includes one topological descriptor: the Kier and Hall index of zero order of the hydrophobic segment of the surfactant and two quantum chemical ones: the total energy (or the heat of formation) and the dipole moment of the surfactant molecules. The established general QSPR between the logarithm of the critical micelle concentration (lg cmc) and the descriptors produces relevant coefficients of multiple determination: r 2=0.9948, for both 29 linear alkyl ethoxylates and ten alkyl phenyl polyethylene oxides, and r 2=0.9965 for only the linear alkyl ethoxylates. The latter produces the same results as those based on the well-known Becher's and Ravey's models.

Critical Micelle Concentrations of Nonionic Surfactants in Organic Solvents: Approximate Prediction with UNIFAC

The objective of this study was to model the critical micelle concentration (cmc) of nonionic surfactants in nonaqueous systems using the UNIFAC group contribution method. For the prediction of the cmc the phase separation approach was used, where the micellar phase is approximated as a second liquid phase resulting from the liquid–liquid equilibrium between the solvent and the surfactant, with the necessary activity coefficients predicted by UNIFAC. The limited amount of literature data for reverse micelle formation in nonaqueous systems was used to test the predictions, varying surfactant type, solvent, and temperature. The most promising model was the modified UNIFAC of B. L. Larsen, P. Rasmussen, and A. Fredenslund (Ind. Eng. Chem. Res.26, 2274 (1987)). Since most nonionic surfactants contain oxyethylene chains, a new set of parameters was evaluated for this group, leading to satisfactory predictions. The average deviation between the predicted and the experimental cmc's was about 0.1 log units.

Critical Incorporation Concentration of Surfactants Added to Micellar Solutions of Hydrophobically Modified Polyelectrolytes of the Same Charge

Polymer−surfactant interactions in aqueous solutions of the surface-active copolymer poly(ethylene oxide)-b-poly(propylene oxide)-b-poly(ethylene oxide)-g-poly(acrylic acid) and a homologous series of alkyl sulfates are studied. When surfactants of the same charge are added to copolymer solutions that already have micelles, the surfactant starts to incorporate into the existing polymer micelle at the critical incorporation concentration (CIC). Surface tension measurements determine the CIC as a local minimum in surface tension as a function of added surfactant. Fluorescence emission measurements using a selective fluorescent probe indicate that the surfactant incorporation is noncooperative. Because the initial incorporation at the CIC only involves a single surfactant entering a nonionic micelle, no counterion condensation is needed, making the tail-length dependence of the CIC similar to the tail-length dependence of the critical micelle concentration of nonionic surfactants.

Prediction of Critical Micelle Concentrations of Nonionic Surfactants in Aqueous and Nonaqueous Solvents with UNIFAC

The UNIFAC group-contribution model is used to predict the critical micelle concentration (cmc) of nonionic surfactants in aqueous and nonaqueous solvents. For predicting the cmc, the phase-separation thermodynamic framework approach is used, where the micellar phase is approximated as a second liquid phase resulting from the liquid−liquid equilibrium between the solvent and the surfactant. The necessary activity coefficients are predicted by UNIFAC. The most promising UNIFAC model for this purpose was found to be the UNIFAC-Lyngby (Ind. Eng. Chem. Res. 1987, 26, 2274). To improve the results for surfactants containing oxyethylene chains, a new set of parameters was evaluated for this group, leading to still better cmc predictions for both water and organic solvents, as well as binary solvent systems.

Measurement of the critical micelle concentration of nonionic surfactants by the first derivative absorption spectrum method.

The absorption maximum of a drug in surfactant solution often shifts at surfactant concentrations above the critical micelle concentration (cmc). The first derivative absorption spectrum (FDAS) was used to evaluate the wavelength shift and to measure the cmc of surfactants.The cmc's of heptaethylene glycol dodecyl ether (HED), octaethylene glycol dodecyl ether (OED) and sodium dodecyl sulfate (SDS) obtained by the FDAS method were 1.2×10-4, 1.4×10-4 and 7.6×10-3 M, respectively. These cmc values were higher than those obtained by the surface tension method (the Wilhelmy plate method) because of the difference of the positions where the values were estimated on the curve (see text). In the measurement of cmc by the FDAS method, less sample and a shorter time are needed, and the reproducibility of this method is satisfactorily high. Though the FDAS method can be utilized for ionic and nonionic surfactants, it is particularly effective for nonionic surfactants, while the previous methods for cmc measurement of nonionic surfactant are generally cumbersome and time-consuming.It was found that the degree of shift-length increased with increasing alkyl chain length of alkylparabens (or alkyl gallates). Therefore, it seems that the use of alkylparabens (or alkyl gallates) of greater alkyl chain length is most convenient in the determination of cmc values by the FDAS method.

Effect of alcohols on the critical micelle concentration of nonionic surfactants in water

Effect of alcohols on the critical micelle concentration of nonionic surfactants in water

Effect of sorbitol and inositol on the critical micelle concentration of nonionic surfactants in water and in aqueous urea

The critical micelle concentrations (cmc) of non-ionic surfactants in water and in aqueous urea with or without hexahydric alcohols, sorbitol and inositol, were determined. In water the cmc's of the surfactants were decreased by the addition of the hexahydric alcohols. In addition, there was a remarkable difference in the decreasing ability between these two hexahydric alcohols. Inositol decreased the cmc's more markedly than sorbitol. In aqueous urea the effect of these hexahydric alcohols on the cmc's and the difference in the decreasing ability between the two alcohols were less than those in water. These results were explained in terms of the effect of the hexahydric alcohols on the structure of water.

Spectrophotometric determination of critical micelle concentration of nonionic surfactants

Spectrophotometric determination of critical micelle concentration of nonionic surfactants

The determination of critical micelle concentrations of nonionic surfactants by charge-transfer solubilization of 7, 7, 8, 8 tetracyanoquinodimethane

The determination of critical micelle concentration (CMC) of homogeneous polyethylene glycol n-dodecyl ethers has been done from spectral change based on the charge-transfer (CT) solubilization of 7, 7, 8, 8-tetracyanoquinodimethane (TCNQ). When TCNQ was solubilized in aqueous solutions of nonionic surfactants, color appeared above the CMC, while there was no color below the CMC. The appearance of color depends on the formation of TCNQ-micelle CT complex. The absorption bands for the complex solutions were observed at 480- to 550-mμ region, 700- to 750-mμ region, and 850 mμ, and these bands are not of the components. The CMC values obtained by this method were found to agree fairly well with those by surface-tension measurements. Also this method has some advantages in discussion of both the type of the interaction of solubilizate with nonionic surfactant and the mechanism of solubilization.

Salt effects on the critical micelle concentrations of nonionic surfactants

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTSalt effects on the critical micelle concentrations of nonionic surfactantsPasupati MukerjeeCite this: J. Phys. Chem. 1970, 74, 21, 3824–3826Publication Date (Print):October 1, 1970Publication History Published online1 May 2002Published inissue 1 October 1970https://doi.org/10.1021/j100715a019RIGHTS & PERMISSIONSArticle Views302Altmetric-Citations18LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (406 KB) Get e-Alerts

Determination of critical micelle concentration of non-ionic surfactants by electrocapillary curves

A method is described for the determination of the critical micelle concentration of non-ionic surfactants by measurement of their effect on the electrocapillary curves for a dropping mercury electrode. The method was compared with the iodine-solubilization, surface tension, and polarographic maximum suppression methods.

Critical Micelle Concentration of Nonionic Surfactants in Water and Carbon Tetrachloride

The critical micelle concentration (CMC) of two nonionic surface-active agents was studied. The micellization properties of polysorbate 80 and sorbitan monooleate were investigated in water and chloroform utilizing iodine as the indicator. Mixtures of polysorbates and sorbitans in various proportions were also tested relative to the CMC for mixed micelles in both solvents. A spectrophotometric method was used to determine the CMC in both solvents; the aqueous systems were also studied by a surface-tension method.