Sodium Lauryl Ether Sulfate Research Articles

Cytotoxicity of lecithin-based nanoemulsions on human skin cells and ex vivo skin permeation: Comparison to conventional surfactant types

As constituents of cellular membranes, lecithins feature high biocompatibility and great emulsifying properties due to their amphiphilicity. Additionally, there are expectations that these naturally occurring emulsifying agents can replace other skin damaging emulsifiers like sodium dodecyl sulfate or sodium laureth sulfate. However, cytotoxicity data of lecithin-based formulations on primary human skin cells are scarce. Thus, we developed nanoemulsions with different kinds of surfactants (amphoteric, anionic and non-ionic), studied the skin permeation of a model drug from this formulations employing Franz-type diffusion cells and monitored their cytotoxicity potential on primary human keratinocytes and fibroblasts using a cell proliferation assay. The skin diffusion studies demonstrated that the amphoteric lecithin-based emulsifiers were superior to non-ionic surfactants in terms of skin permeation, but inferior to anionic emulsifiers. Further, we found that the nanoemulsions containing the amphoteric lecithins as emulsifying agents lead to significantly higher viability rates of both epidermal keratinocytes and dermal fibroblasts than the investigated anionic and non-ionic surfactants. This renders them a promising alternative to conventional emulsifiers used in daily products.

The analysis of the components in modern shampoos for children with the aim of further development of domestic products

Proper care that is adequate to the condition of the newborn’s skin and hair is the necessary condition for maintain­ing health, preventing possible allergic manifestations and various diseases. The main components of a daily skin care are bathing, face, eyes, nose and ears care, etc. At the same time, parents often independently choose, dose and use cosmetic and hygienic, therapeutic and prophylactic products of cleansing action, fully relying on promotional offers, recommendations of their acquaintances. In addition, most often the choice of drugs is influenced by the personal preferences or parents’ tastes, financial ability and general culture. Therefore, the composition of cosmetic preparations for the baby skin and hair should be particularly safe and balanced.Аim. To conduct the analysis of modern products for the baby skin and hair care of various dosage forms, categories and segments, price ranking for the latest trends when selecting active surfactants with a mild action, conditions for their administration, development of foaming bases and creation of hygienic, therapeutic and preventing drugs.Materials and methods. The study of the range of drugs formed within five years by the products of the foaming action of the baby-segment (from birth 0+). Modern competitive tendencies was determined by monitoring this segment of products in the form of shampoos, shampoo-foams, shampoo-gels, a wide range of cost from 25-00 UAH to 650-00 UAH presented by different manufacturers that were in demand with consumers from Ukraine, countries of the European Union and CIS.Results. The analysis of the composition of foaming agents in the baby-segment (from the birth of 0+) shows that when selecting the basic substances – detergents the advantage is given to substances with a low threshold of the irritant action, such as Disodium Laureth Sulfosuccinate, Sodium Lauroyl Sarcosinate, Sodium Lauroyl Glutamate, Ammonium, Laureth Sulfate and others. However, these surfactants are not able to independently fully provide high functional and consumer properties of the final product (foaming ability, foam number, pH, viscosity), while having the necessary dermatological characteristics.Conclusions. The data obtained indicate that it is important to search for new and promising substances in order to create safe, hypoallergenic foaming bases for baby cosmetics. There is a need for research to determine the conditions for the introduction of the priority primary and secondary surfactants.

Preparation and Property of Perfluoropolyether Emulsions.

Perfluoropolyether (PFPE) glycerol emulsions were prepared. Three different green surfactants (AES (sodium laureth sulfate), APG (alkyl polyglycoside), and SDS (sodium dodecyl sulfate)) were chosen to emulsify the PFPE. Their properties and performance in shampoo were also investigated. Centrifuge stability measurements show that three PFPE emulsions have good stability. They are stable for 60 min when the centrifugal speed is 6000 r/min. In addition, a change of droplet size was observed with time. Moreover, its rheological properties and application performance was studied. The AES emulsion was the most stable emulsion and it was found to improve the slip and lubricity performance of the cotton, so it has potential applications in shampoo.

Rheo-physical characterization of microstructure and flow behavior of concentrated surfactant solutions

Processing-relevant relationships between the microstructure and flow behavior of concentrated surfactant solutions were determined by a combination of basic rheological experiments, rheo-flow velocimetry tests, and flow birefringence measurements. The most common surfactant microstructures found in liquid soaps and other consumer care products—spherical, worm-like, and hexagonally packed micelles and lamellar structures—were recreated by varying the concentration of sodium laureth sulfate in water from 20 to 70 wt% and adding salt in some cases. It was found that common features of flow curves, such as power-law shear thinning behavior, resulted from a wide variety of material responses including shear-induced wall slip in micellar samples and plug flow in lamellar samples. Knowledge of key processing-structure-property relationships for concentrated solutions will allow engineers to develop more efficient industrial workflows for the scalable manufacturing of materials and feedstocks with reduced economic and environmental costs.

Oil drop deposition on solid surfaces in mixed polymer-surfactant solutions in relation to hair- and skin-care applications

The deposition of oil drops on solid substrates from mixed solutions of surfactants and cationic polymer is investigated. The used anionic surfactants are sodium laurylethersulfate (SLES) and sulfonated methyl esters (SME); the zwitterionic surfactant is cocamidopropyl betaine (CAPB). A new method, called the pressed drop method (PDM), was proposed to study the drop adhesion to substrates of different hydrophobicity. The PDM allows one to detect the presence or absence of drop adhesion at different degrees of dilution of the initial solution and, thus, to determine the threshold concentration of drop adhesion. The results show that the increase of the fraction of CAPB in the mixture with the anionic surfactant suppresses the oil-drop deposition; SME provides easier drop adhesion than SLES; the addition of NaCl enhances, whereas coco-fatty-acid-monoethanolamide (CMEA) suppresses the drop deposition; no drop adhesion is observed in the absence of polymer. The drop-to-substrate adhesion is interpreted in terms of the acting surface forces: polymer bridging attraction; hydrophobic attraction between segments of adsorbed polymer brushes and electrostatic forces. From viewpoint of applications, the PDM experiments enable one to compare the performance of various components in personal care formulations and to optimize their composition with respect to the oil-drop deposition.

Synthesis of halal membrane capsule from water soluble chitosan by adding sodium lauryl ether sulphate

Membrane capsule has been synthesized from water soluble chitosan (WSC), agar, and Sodium Lauryl Ether Sulphate (SLES). The concentration of agar used 0.02% (v/v) and the concentration of SLES up to 0.16% (v/v). WSC has been synthesized from shrimp shells, shrimp shells through demineralization, deproteination and deacetylation. After going through 3 processes chitosan converted into WSC by depolymerisation process. Degree of deacetylation (DD) of WSC was calculated based on FTIR baseline method, the value of DD is 77.9%. Based on FTIR spectra showed that the obtained film capsule shell had vibration from its constituent molecules, i.e. chitosan, agar and SLES. Based on tensile test data, it showed that the increasing of SLES concentration would increase the elasticity of shell matrix. Swelling test data in water and 0.1 N HCl showed the greatest value in capsule film with SLES concentration 0.12% is 420.27% and the capsule can be degraded (broken) in 20th minutes. Capsule membrane with SLES concentration 0.12% has the largest degradation value in water and 0.1 N HCl that is 70.91% and 81.32%. Based on research data obtained that the membrane with SLES concentration 0.12% that most appropriate with commercial capsule.

Sunflower Acid Oil‐Based Production of Rhamnolipid Using Pseudomonas aeruginosa and Its Application in Liquid Detergents

AbstractUtilization of industrial waste as substrates for the rhamnolipid synthesis by Pseudomonas aeruginosa is a worthy alternative for conventionally used vegetable oils and fatty acids to reduce the production cost of rhamnolipid. Sunflower acid oil (SAO), a by‐product of the oil industry, contains 70% 18:0 fatty acid, with oleic acid as a major component. In this scope, production and analysis of rhamnolipid was successfully demonstrated using SAO as a new substrate. Pseudomonas aeruginosa produced rhamnolipid (a glycolipid biosurfactant) at a maximum concentration of 4.9 g L−1 with 60 g L−1 of SAO in the medium. Structural properties of rhamnolipid biosurfactant are confirmed using thin layer chromatography (TLC), high performance liquid chromatography (HPLC), and fourier transformed infrared spectroscopy (FTIR) analysis. Further surface‐active properties of the crude rhamnolipid were evaluated by measuring surface tension and emulsification properties. The synthesized rhamnolipid reduced the surface tension of water to 30.12 mN m−1 and interfacial tension (against heptane) to 0.52 mN m−1. Moreover, rhamnolipid shows the highest emulsification index (above 80%) for vegetable oils. This study confirms the use of SAO as a potential substrate for rhamnolipid production. The synthesized rhamnolipid was incorporated in liquid detergent formulation along with alpha olefin sulfonate (AOS) and sodium lauryl ether sulfate (SLES). The performance properties including foaming and cleaning efficiency of liquid detergent were compared.

EFFECT OF NOZZLES, APPLICATION RATES, AND ADJUVANTS ON SPRAY DEPOSITION IN WHEAT CROPS

ABSTRACT The use of insecticides is common in pest management in wheat crops but may lead to higher production costs and environmental contamination. Therefore, a more comprehensive and uniform distribution of plant protection products in the desired target is recommended. The objective of this study is to evaluate the effect of different spray nozzles, application rates, and adjuvants on droplet spectrum and spray deposition in wheat crops. The physicochemical characteristics of the spray mixture, droplet spectrum, and spray deposition in wheat plants were evaluated. The lower application rate (75 L ha−1) combined with the use of the twin flat fan tip AS7030 and the adjuvant sodium lauryl ether sulfate (SLES) yielded droplets with a larger diameter. However, insecticide spraying using hollow cone tip MGA 015 without adjuvants provided the highest percentage of droplets susceptible to drift. SLES significantly decreased the percentage of drift by increasing droplet size, and the adjuvant silicone, d-limonene, and polyester copolymer increased spray deposition. The evaluated adjuvants increased the electrical conductivity and reduced the surface tension of the spray mixtures. These results indicate that it is possible to reduce the application rate from 150 to 75 L ha−1 without affecting spray deposition on wheat leaves.

Analysis of Preservative Capacity for Contemporary Iranian Shampoos

Preservative capacity is measured for seventeen currently accessible Iranian made shampoo products. Upon purchase, bacterial counts show no trace of any microbial contamination. The shampoo bottles are distributed to seventeen female graduate students, residing at the time in different dormitories of Tarbiat Modares University (TMU). After 40 days, the allocated bottles are returned and their bacterial counts repeated, under the same conditions. To our surprise, no trace of any microbial contamination is observed. Three possibilities are considered. 1) The factory employed preservative(s) act very efficiently. 2) The shampoo component(s) are themselves bactericidal. 3) Existence of sanitary conditions and the absence of any microbial contaminants at TMU! Evidently, the third possibility is ruled out. The second choice is also discarded, because practically no significant antimicrobial activity is demonstrated by any of the four main ingredients of the shampoos including sodium lauryl ether sulfate (SLES), betaine, coconut fatty acid, and glycerin. Hence, the most likely possibility is the first one, since upon deliberate contamination of the seventeen brands; the factory employed preservatives [5-chloro-2-methyl-4-isothiazolin-3-one and 2-methyl-4-isothiazolin-3-one (KATHON CG)] prove highly bactericidal against four major contaminants: Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, and the methicillin-resistant Staphylococcus aureus (MRSA).

Simultaneous Determination of Two Alcohols and One Anionic Surfactant in Commercial Liquid Cleaners Using Partial Least Square Regression by Fourier Transform Infrared Spectrometry

Abstract A simple, fast, efficient, and reagent free procedure without any chemical pretreatment has developed for simultaneous analysis of sodium lauryl ether sulfate (SLES), ethanol and isopropanol in some commercial cleaners. This determination was carried out using attenuated total reflectance Fourier transform infrared spectrometry (ATR-FTIR) and multivariate analysis. Partial least-squares (PLS) statistical method for quantitative analysis was used to determine the spectra of three components in a mixture of liquid household detergents. The statistical parameters such as Root Mean Square Error of Calibration (RMSEC), Root Mean Square Error of Cross Validation (RMSECV), Standard Errors of Prediction (SEP) and square correlation coefficient (R2) were obtained 0.07, 0.18, 0.16 (v/v%), 0.15, 0.32, 0.69 (v/v%), 0.22, 0.34, 0.57 (v/v%) and 0.9995, 0.9996 and 0.9998 for SLES, isopropanol and ethanol respectively. Good agreements were achieved between our results and the reference and standard values.

Fatty Acid Potassium Had Beneficial Bactericidal Effects and Removed Staphylococcus aureus Biofilms while Exhibiting Reduced Cytotoxicity towards Mouse Fibroblasts and Human Keratinocytes.

Wounds frequently become infected or contaminated with bacteria. Potassium oleate (C18:1K), a type of fatty acid potassium, caused >4 log colony-forming unit (CFU)/mL reductions in the numbers of Staphylococcus aureus and Escherichia coli within 10 min and a >2 log CFU/mL reduction in the number of Clostridium difficile within 1 min. C18:1K (proportion removed: 90.3%) was significantly more effective at removing Staphylococcus aureus biofilms than the synthetic surfactant detergents sodium lauryl ether sulfate (SLES) (74.8%, p < 0.01) and sodium lauryl sulfate (SLS) (78.0%, p < 0.05). In the WST (water-soluble tetrazolium) assay, mouse fibroblasts (BALB/3T3 clone A31) in C18:1K (relative viability vs. control: 102.8%) demonstrated a significantly higher viability than those in SLES (30.1%) or SLS (18.1%, p < 0.05). In a lactate dehydrogenase (LDH) leakage assay, C18:1K (relative leakage vs. control: 108.9%) was found to be associated with a significantly lower LDH leakage from mouse fibroblasts than SLES or SLS (720.6% and 523.4%, respectively; p < 0.05). Potassium oleate demonstrated bactericidal effects against various species including Staphylococcus aureus, Escherichia coli, Bacillus cereus, and Clostridium difficile; removed significantly greater amounts of Staphylococcus aureus biofilm material than SLES and SLS; and maintained fibroblast viability; therefore, it might be useful for wound cleaning and peri-wound skin.

Stability of polylactide as potential packaging material in solutions of selected surfactants used in cosmetic formulae

Currently the use of different types of cosmetics is an integral part of our life. For this reason the stability of packaging materials in contact with popular cosmetic ingredients is crucial. In this work a study on the properties of polylactide (PLA) as potential packaging in selected surfactant solutions (sodium lauryl sulfate (SLS) and sodium laureth sulfate (SLES)) has been carried out. For referential purposes immersion in distilled water has also been conducted. After previously established time, the difference in mass of polymer films as well as in the average molecular weight of PLA has been measured. Moreover the changes in surface morphology and in thermal parameters of PLA have been studied. The results indicate that the most significant changes in the properties of the PLA as well as in pH of the studied mediums have been observed in the case of storage in SLES solution. This phenomenon occurs because the sodium laureth sulfate is responsible for the increase in acidity, resulting from the SLES self-hydrolysis. Obtained result can be useful for industry in order to protect cosmetic products and consumers.

Rheological characterisation of chitosan/sodium lauryl ether sulfate complexes

Chitosan is a cationic biopolymer, which attracts more and more attention in recent years, due to its exceptional physical and chemical properties, expressive biocompatibility and possibilities of obtaining from renewable sources. Formed polymer/surfactant complexes affect changes in the rheological properties and the final result is the formation of coacervates. The purpose of this study was to investigate the rheological properties of aqueous solutions of cationic polyelectrolyte, chitosan and sodium lauryl ether sulfate (SLES), an anionic surfactant, widely used in the cosmetics industry. Using the Thermo Haake RS600 rheometer, changes in the rheological and elastic properties of chitosan and SLES mixtures have been identified, gained as a result of the interaction of the components. In all examined samples coefficient of thixotropy was increasing with increase SLES concentration and achieves a maximum value at the mass ratio chitosan:SLES 1:2, after which it reduces. The oscillatory measurements in mixtures, performed by amplitude sweep method at low oscillating frequency 1 Hz, show that the linear viscoelastic region increases with increasing SLES concentration up to the same chitosan:SLES mass ratio. By monitoring the changes in the rheological parameters of the mixtures over five days, it was observed that the viscosity, the coefficient of thixotropy and elasticity were increasing, indicating that changes in the system occur over a longer period of time. In that manner, obtained results indicate the possibility of using rheological methods for a more detailed description of the interaction in the chitosan/SLES mixtures, important for their application in cosmetics and pharmaceutical industries.

ECOTOXICITY OF FOAMING AGENT CONDITIONED SOILS TESTED ON TWO TERRESTRIAL ORGANISMS

Huge amounts of soil debris are produced during the underground excavation with Earth Pressure Balance-Tunnel Boring Machines (EPB-TBM). Soil debris may contain residual concentrations of the anionic surfactant sodium lauryl ether sulphate (SLES), the main component in some foaming agents used as excavation additives. The reuse of this debris or its discharge as waste is a critical environmental question in construction engineering. There are only few studies on ecotoxicological effects on soil debris coming from a real excavation site. The aim of this study was to evaluate the ecotoxicity of two deep soils, with different lithological compositions, conditioned with three foaming agents. In some cases, lime was added to the soil. The soils were placed in mesocosms (1 m3) to simulate the temporary storage of the soil debris at a construction site. At fixed times, soil sub-samples were collected and ecotoxicological tests on terrestrial organisms (Lepidium sativum, Eisenia foetida) and an assessment of SLES concentration were performed with soils and aqueous elutriates produced from them. Results showed that at day 28, a SLES reduction was observed in both the soil and aqueous elutriates, with various rates of decrease. The differences were due to different soil lithological compositions and foaming agent products composition. In general, the two soils were not suitable for both plant growth and earthworm reproduction, but in Soil 1 the earthworm mortality was very low, except when lime was added. Tests with soil elutriates showed that 7 days after conditioning no toxic effect was found for the organisms tested.

Effect of synthetic surfactants and soapwort (Saponaria officinalis L.) extract on skin-mimetic model lipid monolayers

The effect of a saponin-rich extract from rhizomes of Soapwort (Saponaria officinalis L) and four synthetic surfactants: sodium lauryl sulphate (SLS), sodium laureth sulphate (SLES), ammonium lauryl sulphate (ALS) and cocamidopropyl betaine (CAPB) on two model lipid monolayers is analyzed using surface pressure, surface dilatational rheology and fluorescence microscopy. The following monolayers were employed: dipalmitoylphosphatidylcholine/cholesterol mixture in a molar ratio of 7:3 (DPPC/CHOL) and Ceramide [AP]/stearic acid/cholesterol in a molar ratio of 14:14:10 (CER/SA/CHOL). They mimicked a general bilayer structure and an intercellular lipid mixture, respectively. Both lipid mixtures on Milli-Q water were first compressed to the initial surface pressure, Π0 = 30 mN/m and then the subphase was exchanged with the respective (bio)surfactant solution at 1% (w/w). All four synthetic surfactants behaved in a similar way: they increased surface pressure to about 40 mN/m and reduced the storage modulus of surface dilational surface rheology, E′, to the values close to zero. The corresponding fluorescence microscopy pictures confirmed that the lipids mimicking the stratum corneum components were almost completely removed by the synthetic surfactants under the present experimental conditions. The components of the Soapwort extract (SAP) increased surface pressure to significantly higher values than the synthetic surfactants, but even more spectacular increase was observed for the storage modulus of the SAP-penetrated lipid monolayers (up to E′= 715 mN/m).

Markov Chain Modeling of Surfactant Critical Micelle Concentration and Surface Composition.

A Markov chain (MC) model has been used to model the following binary surfactant mixtures: linear alkylbenzenesulfonate (LAS4)/octaethylene glycol monododecyl ether (C12E8) at 10 and 25 °C, LAS6/acidic sophorolipid (AS), C12Betaine/C12Maltoside, sodium lauryl ether sulfate (SLES2)/C12E8, and rhamnolipid (R1)/LAS6. The critical micellar concentration and the composition of the adsorbed layer, for each system, can be modeled using the same monomer reactivity ratio values, g1 and g2. This implies that the interactions between the surfactants in the bulk solution and at the interface are the same, within error. For the LAS4/C12E8 system at 25 °C, the ranges of g1 and g2 values which can model both sets of data are within 0.03-0.05 and 1.55-2.10, respectively; g1 ≪ g2 implies that C12E8 is significantly more surface active than LAS4. The MC model indicates a negative change in the free energy upon mixing for all of the surfactant systems, consistent with the literature. The interfacial mixing behavior of LAS4/SLES2 is inferred from the results of the MC analysis of the LAS4/C12E8 and SLES2/C12E8 systems, which share a common surfactant partner in C12E8, and the prediction is in line with the published data.

Human breast cancer decellularized scaffolds promote epithelial-to-mesenchymal transitions and stemness of breast cancer cells in vitro.

Breast cancer, with unsatisfactory survival rates, is the leading cause of cancer-related death in women worldwide. Recent advances in the genetic basis of breast cancer have benefitted the development of gene-based medicines and therapies. Tissue engineering technologies, including tissue decellularizations and reconstructions, are potential therapeutic alternatives for cancer research and tissue regeneration. In our study, human breast cancer biopsies were decellularized by a detergent technique, with sodium lauryl ether sulfate (SLES) solution, for the first time. And the decellularization process was optimized to maximally maintain tissue microarchitectures and extracellular matrix (ECM) components with minimal DNA compounds preserved. Histology analysis and DNA quantification results confirmed the decellularization effect with maximal genetic compounds removal. Quantification, immunofluorescence, and histology analyses demonstrated better preservation of ECM components in 0.5% SLES-treated scaffolds. Scaffolds seeded with MCF-7 cells demonstrated the process of cell recellularization in vitro, with increased cell migration, proliferation, and epithelial-to-mesenchymal transition (EMT) process. When treated with 5-fluorouracil, the expressions of stem cell markers, including Oct4, Sox2, and CD49F, were maximally maintained in the recellularized scaffold with decreased apoptosis rates compared with monolayer cells. These results showed that the decellularized breast scaffold model with SLES treatments would help to simulate the pathogenesis of breast cancer in vitro. And we hope that this model could further accelerate the development of effective therapies for breast cancer and benefit drug screenings.

A molecular dynamics simulation of the structure of sodium lauryl ether sulfate and poly(vinyl alcohol) at the air/water interface

The influence of a poly(vinyl alcohol) (PVA) molecule on the air/water interfacial structure of adsorbed sodium lauryl ether sulfate with one polyethylene oxide group (SLE1S) was investigated using molecular dynamics simulations. Increasing SLE1S surface density increases the interface thickness and forces both SLE1S and PVA molecules to migrate towards the air (actually vacuum) to different degrees. While most surfactants, when dilute, align parallel with the interface, increasing surfactant surface density forces tail groups gradually to align more perpendicularly to the interface. The three types of oxygen atoms in the SLE1S head group, i.e. the ionic, ester and ether oxygen atoms, form three distinct hydration shells, with PVA monomers appearing both within these shells and between the second and third shell due to its own hydrogen bonding with water and excluded volume of surfactant and water. The ionic oxygen atoms form more hydrogen bonds with water molecules and PVA than do the ester and ether oxygen atoms. The addition of PVA decreases slightly the number of hydrogen bonds between the surfactant oxygen atoms and the water molecules, as PVA chains form new hydrogen bonds with both of them. With increasing surfactant concentration, the PVA is pushed away from the bulk water, decreasing the number of the hydrogen bonds between it and water. These results are relevant to the use of polymers to aid surfactant in aqueous foaming applications.

Molecular factors governing the viscosity peak of giant micelles in the presence of salt and fragrances

HypothesisThe formation of transient networks of giant micelles leads to a viscosity peak when salt is added to aqueous solutions of charged surfactants. It is the consequence of an increase of the packing parameter due to charge screening of the surfactant headgroups, leading to a continuous transformation of the aggregates from spherical to wormlike micelles, and finally to branched networks. It should therefore be possible to predict the macroscopic viscosity of entangled giant micelles by modelling the packing parameter at nanoscale. ExperimentsA thermodynamic model is presented with a minimum of adjustable parameters, where branched networks are considered to be built from three coexisting microphases: cylinders, endcaps, and junctions. We use spontaneous packing parameters, in which the whole molecular length instead of the commonly used hydrocarbon chain length is considered. Standard reference chemical potentials and subsequently the occurrence of each microphase can be explicitly derived at specific electrolyte concentrations. Effective micellar length of giant micelles can be obtained from the microphase composition and is subsequently used to calculate the viscosity. FindingsThe model successfully predicts position and intensity of the viscosity maximum observed in experimental salt curves of sodium laureth sulfate (SLES). The robustness of the model was further investigated for various types of added salts or fragrance oils that affect differently spontaneous packing parameters or interfacial bending energy. An excellent agreement of the simulated salt curves with experimental data was achieved.

Synergism and Interfacial Property Study of Sodium Lauryl Ether Sulfate and Polysorbate 80 at the Air–Water Interface

AbstractAdsorption and micellization behavior of sodium lauryl ether sulfate (SLES) and Polysorbate 80 (PS80) was investigated using equilibrium and dynamic surface tension and foaming measurements. Critical micelle concentration (CMC) was determined using surface tension and dye (Sudan red III) solubilization method with the help of the Wilhelmy plate method and ultraviolet–visible spectroscopic method, respectively. The strength of the interaction for micellization and adsorption between the mixtures are calculated using the β interaction parameter. The SLES‐PS80 mixture shows synergistic interaction with β = −8.0. The dynamic and foaming behavior at constant bulk concentration showed a higher t * value with lowest foaming at 50% mole fraction of SLES. The emulsification index (EI) of pure SLES, pure PS 80, and 1:1 SLES‐PS 80 composition was studied using neem, karanja, and sunflower oils. Karanja and sunflower oils show a higher EI for mixture than the pure surfactants, whereas neem shows a lower EI for mixture than pure surfactants.