Surface Activity Parameters Research Articles

Synthesis and characterization of a series of amidine-based switch surfactants: toward environmental surface-active materials

A series of newly structured two-tailed cationic surfactants were synthesized via a carbonyl amine condensation reaction aimed at reducing the bioaccumulation of conventional surfactants while maintaining their excellent surface properties. Long-chain alkyl amine compounds can be reversibly converted into charged surfactants through CO2/H2O treatment and an alkyl chain length of between C8 and C12. The structures were characterized by IR,1H NMR and 13C NMR. The main surface activity parameters of the surfactants, containing cmc, γcmc pC20, cmc/С20, Γm and Αmin, were determined. The switching properties of N’-alkyl-N, N-dimethylalkamidine bicarbonate and N, N-dimethyl-N-alkylamidine bicarbonate were demonstrated by investigating their conductivities in solution and carrying out their emulsification-emulsion-breaking experiment.

Thermodynamic and surface active investigations of aqueous solution of sodium dodecylbenzene sulfonate in presence of builders: sequestration of Ca2+ ions and interaction with H2O2

Abstract The current investigation examines the micellization process of sodium dodecylbenzene sulfonate in aqueous media with builders at temperatures ranging from 298.15 K to 313.15 K. Using conductometry and tensiometry analyses, the study examines changes in micellar properties in different surfactant solutions, focusing primarily on CMC. Additionally, the variation of CMC with temperature was used to determine the thermodynamic parameters of micellization such as ∆ G m ° , Δ H m ° , ${{\increment}G}_{\mathrm{m}}^{{}^{\circ}},{\Delta }{H}_{\mathrm{m}}^{{}^{\circ}}\text{,}$ and ∆ S m ° ${{\increment}S}_{\mathrm{m}}^{{}^{\circ}}$ . This approach provides valuable insights into the behavior of the surfactant and the different intermolecular interactions involved in the system. The different surface active parameters π CMC, A min, and Γ max were elucidated using tensiometry via the Wilhelmy plate technique. Moreover, the capacity of the builder to sequester calcium ions was studied using a well-established titration method, offering valuable insights into their effectiveness. Their efficiency under oxidative conditions, particularly in preventing the interaction between copper ions and hydrogen peroxide, was evaluated. This article provides a comprehensive analysis of different builders when used with the anionic surfactant, sodium dodecylbenzene sulfonate. Their combination provides improved efficiency in protecting metals from corrosion, extracting heavy metals from polluted soils, and in personal care products such as shampoos and soaps.

Surface activity of Lupinus angustifolius (blue lupine) seed extracts

Surface tension (γeq) of the seed extracts of four lupine cultivars showed values in the range 44.9–46.4 mN/m. The surface compression elasticity (E') of the adsorbed layers and foaming capacity (FC) also showed similar values (E' ∼ 30 mN/m, FC ∼ 100%). The effect of defatting prior to extraction at pH 8.5 depends on the solvent employed – hexane and dichloromethane improved the subsequent protein extraction yield, while ethanol reduced it. The effect of defatting on surface tension could be positive (for hexane and ethanol) or negative (for dichloromethane). Generally, defatting improved the surface compression rheological and foaming parameters. On the other hand, fractionation of the extracts obtained at pH 8.5 from hexane-defatted seeds did not improve significantly the surface activity parameters. Some improvement with respect to the unfractionated extracts was observed only for the extracts of undefatted seeds. γeq, E', E" and FC isotherms confirm the surfactant-like behavior of the lupine seed extracts.

Biomass-based carbon aerogels with interconnected pores and controllable Zn–N sites for CO2 electroreduction

The rational design of renewable, highly active, and selective catalysts has always been the key to the practical application of CO2 electroreduction. In this study, biomass-based Zn/N doped carbon aerogels were fabricated for high-selectivity electrical reduction of CO2 to CO. After in situ Zn/N doping, carbon aerogels exhibited interconnected pores, high surface area, and exposed active sites, and their physicochemical properties are significantly affected by pyrolysis temperature. When the pyrolysis temperature increased to 950 °C, the number of surface active sites and pore structure parameters of carbon aerogels decreased significantly due to the escape of zinc and nitrogen. CAZN-850 exhibited the highest specific surface area of 1317.0 m2/g and abundant Zn–N sites, which results in its high activity and selectivity for electroreduction of CO2 to CO (FECO = 89 % at −1.0V vs. RHE). Moreover, the stability test results for CO2RR showed that the reduction value of FECO for Zn/N doped carbon aerogels was only 5 % under long-time operation. This work provides a new idea for the design of biomass-based catalysts for CO2 electroreduction.

Study on the properties of branched-chain alkyl glycoside nonionic surfactant and anionic surfactant in a mixed system

Abstract The surface activity, intermolecular interactions and thermodynamic parameters of a mixture of a nonionic surfactant (branched-chain alkyl glycoside (IG-10)) and an anionic surfactant (alcohol ether carboxylic acid (90H)) were investigated and the wetting, emulsifying and foaming properties of the mixed system were also evaluated. The results show that there is a mutual attraction at the mixed micelles and gas/liquid interfaces formed by the two surfactants. The thermodynamic parameters show that the formation of mixed micelles from two different surfactants is a non-ideal process. In terms of application performance, the wetting ability and foaming properties of the mixed system showed good synergistic effects, with the wetting time of the mixed system being shorter than that of the two single surfactant systems and the foam stability being weaker than that of the single system. The best emulsifying capacity was obtained when the mass fraction of 90H was 50 %.

Unraveling the surface activity and micellization characteristics of linear alkyl benzene sulfonate in aqueous solution

Abstract The aggregation behavior of various neutralizing agents (monovalent and diamine bases) has been investigated for linear alkylbenzene sulfonate. Measurements employing conductivity at temperature (298.15 K, 303.15 K, 308.15 K, and 313.15 K) and surface tension at 298.15 K have been determined to study micellization and surface active properties. The conductivity versus concentration plot elucidated CMC and dissociation of counterion (α). Additionally, surface active parameters ϒCMC, A min, π CMC, and τ max were investigated via tensiometry using the Wilhelmy plate procedure. The wettability characteristic of the surfactant solution was determined using contact angle analysis. Furthermore, the particle size parameters were determined using DLS measurements. The Gemini salts of LABS portrayed improved efficiency and demonstrated economical in domestic and industrial applications.

Quality by design approach-based fabrication and evaluation of self-nanoemulsifying drug delivery system for improved delivery of venetoclax.

Breast cancer is reported as one of the most prevalent non-cutaneous malignancies in women. Venetoclax (VEN) is an approved BCl-2 inhibitor for the treatment of chronic myeloid leukemia with very limited oral bioavailability and exhibits an enormous impact on breast cancer. In the current investigation, venetoclax-loaded self-nanoemulsifying drug delivery systems (VEN-SNEDDS) were designed and fabricated to improve the aqueous solubility, permeability, and anticancer efficacy of VEN. Various surface-active parameters of the reconstituted SNEDDS were determined to scrutinize the performance of the selected surfactant mixture. Central composite design (CCD) was used to optimize the VEN-SNEDDS. The globule size of reconstituted VEN-SNEDDS was 71.3 ± 2.8nm with a polydispersity index of 0.113 ± 0.01. VEN-SNEDDS displayed approximately 3-4fold, 6-7fold, and 5-6fold reduced IC50 as compared to free VEN in MDA-MB-231, MCF-7, and T47 D cells, respectively. VEN-SNEDDS showed greater cellular uptake, apoptosis, reactive oxygen species generation, and higher BAX/BCL2 ratio with decreased caspase 3 and 8 and BCL-2 levels in the MDA-MB-231 cells compared to pure VEN. VEN-SNEDDS exhibited approximately fivefold enhancement in Cmax and an improved oral bioavailability compared to VEN suspension in in vivo pharmacokinetic studies.

Multimodal lemongrass oil based topical nanoemulgel ingrained with ferulic acid for wound healing activity

The lemongrass oil (LMGO) obtained from Cymbopagan citratus betrays anti-bacterial and anti-oxidant properties. A natural anti-oxidant, ferulic acid (FA) is an angiogenic agent found in vegetables, fruits exhibiting potent anti-inflammatory activity aiding in wound healing process. This investigation was aimed to formulation and optimization of the FA loaded LMGO nanoemulsion (NE) by phase inversion composition method, that has not been well explored by using Box Behnken design (BBD). The surface-active parameters of surfactant mixture (Smix) were evaluated for the selection of Smix ratio in conjunction with conventional pseudo ternary phase diagram. The surface-active parameters included critical micelle concentration (CMC), surface excess concentration (Гmax), minimum surface area adsorbed by surfactant molecules (Amin), effectiveness of adsorption (Πcmc) along with Gibbs thermodynamic parameters for micellization and adsorption. The BBD was employed to optimize the formulation by studying the interaction effects of four independent variables including oil (X1), surfactant mixture (X2), stirring speed (X3), and stirring time (X4) on three responses such as, mean droplet size (Y1), polydispersity index (PDI) (Y2) and percentage transmittance (Y3). At the optimal variable levels (X1 = 10%;X2 = 30%;X3 = 500 rpm and X4 = 5 min), the responses were found to be 26.15 ± 0.58 nm, 0.04 ± 0.01 and 99.76 ± 0.06% for Y1, Y2, Y 3, respectively. The optimized NE exhibited stability in terms of droplet size, PDI, percentage transmittance and surface tension on 5, 10 and 100 times dilution with water. These findings may be useful for designing NE with low energy methods with greater kinetic stability for therapeutic applications. The FA content was determined and found be 98.11 ± 0.51%. The optimized FA loaded NE (FLGO) was incorporated with 2% carbopol®940 for the development of nanoemulgel. The developed FA loaded nanoemulgel (FLGO-G) system demonstrated the pseudoplastic behaviour, desirable for topical application. The blank lemongrass oil nanoemulsion loaded gel (LGO-G) and FLOG-G formulation showed 52.82 ± 0.33% and 75.62 ± 0.16% of DPPH free radical % inhibition. The formulations also showed in-vitro antibacterial activity against S. aureus. The in vivo wound healing efficacy of LGO-G and FLGO-G were studied in male wistar rat, the levels of IL-6 and TNF-α reduced to greater extent.

Palm kernel oil mucilage as a source of bio-based cationic surfactants for effective control of water surface pollution: Synthesis, surface activity and petroleum capacities

Water contamination is a serious environmental issue with great negative impacts on the health of living organisms. Petroleum films from oil slicks represent one of the major water pollutants. The utilization of bio-based surfactants derived from natural sources/wastes can be an eco-friendly solution to address this problem. In such direction, a new series of palm kernel oil mucilage (PKOM)-based cationic surfactants (4a–e) has been synthesized through an efficient procedure and the structures were characterized spectroscopically. Firstly, the free fatty acids mixture was extracted from PKOM, reduced with LiAlH4 to the corresponding alcohols mixture and esterified with chloroacetic acid to afford fatty chlorides mixture. Parallelly, tertiary amine-tethering various aryl sulfonamides (3a–e) were prepared from the reaction of sulfonyl chlorides with a primary amine-tertiary amine hybrid compound. Finally, the target cationic surfactants were obtained via quaternization of the tertiary-N in 3a–e with the fatty chlorides. The surface activity and thermodynamic parameters of the synthesized bio-based surfactants have been determined. Moreover, the ability of these compounds to collect or disperse petroleum thin films in different water types was evaluated. Interestingly, almost all compounds exhibited strong abilities to collect or disperse these films from water even at high salinity percent (9 % NaCl).

Thermodynamics and micellization behavior of choline based ionic liquids in presence of drug Cetrizine dihydrochloride

Abstract Ionic liquids (IL) have attained immense interest as substitutes for conventionally available surfactants because of their exceptionally favorable physicochemical properties. Most synthesized IL surfactants are not environmentally benign, and even utilizing high concentration, they form unstable micelles. In this regard, we have synthesized biocompatible and halogen free choline based ionic liquids by varying anions (choline oleate and cholinium bis(2-ethylhexyl) sulfosuccinate) and further investigated their micellization behavior in presence of the drug Cetrizine dihydrochloride. Characterizations of these synthesized ionic liquids were performed utilizing 1HNMR spectroscopy. The thermodynamic investigation and determination of various surface-active parameters were based on tensiometry and conductometric titrations. The CMC value of choline oleate ([CHO][Ole]) was found to be lower than that of [Cho][AOT] and thus it has a better surface activity. The thermodynamic parameters ( Δ G m 0 ${{\Delta}G}_{m}^{0}$ , Δ H m 0 ${{\Delta}H}_{m}^{0}$ , and Δ S m 0 ${{\Delta}S}_{m}^{0}$ ) signifies spontaneous, stable, exothermic and entropy driven nature of micellization process. The various interfacial and surface parameters have been evaluated employing tensiometry. These environmentally friendly ionic liquids have been utilized as substitute for conventional surfactants including their applications in biology and pharmaceutical industries.

Mixed micellization analysis of tri-substituted SAIL and amphiphilic drug mixture in aqueous/salt media at diverse temperatures

Abstract The present work aimed to study the mixed micellar behaviour of a tri-substituted imidazolium based surface-active ionic liquid (SAIL), 1-tetradecyl-2,3-dimethylimidazolium bromide [C14bmim][Br], with a drug Nortriptyline hydrochloride (NOT) in the water/salt (Na2SO4) medium using surface tension measurements (298.15 K) alongwith conductivity measurements (298.15K–313.15K). Lower experimentally obtained cmc values compared to their ideal values suggest that the investigated amphiphiles interact strongly. The values of micellar mole fraction (X 1) based on the several proposed models (Rubingh, Motomura, and Rodenas) and the ideal micellar mole fraction (X id ) were assessed, and the predicted outcomes indicate that NOT has a significant contribution to the formation of mixed micelles, which increases as the [C14bmim][Br] mole fraction is increased. The negative values of micellization’s Gibbs free energy (ΔGm 0) between the examined amphiphiles were an indication of spontaneous mixed micelle formation. Micellar changes in entropy (ΔSm 0) and enthalpy (ΔHm 0) were also computed and discussed. Using surface tension measurements, surface-active parameters like surface tension at cmc (γ cmc ), minimum surface area per IL molecule (A min), maximum surface excess concentration (τ max), effectiveness of surface tension reduction (π cmc ), and cmc of mixed system have been estimated. The results showed an improved adsorption and micellization properties of these mixtures which will surely contribute to the tremendous rise of these mixed systems in drug delivery applications.

Investigation the effect of different ionic liquids based-aryl imidazole on the onset precipitation of asphaltene

Precipitation and deposition of asphaltene are considered as catastrophic issues facing the petroleum industry. Asphaltene deposition mainly occurs at variety places such as formation pore spaces, pumps, pipelines, wellbore, wellhead, tubing, surface facilities and safety valves causing operational problems, production deficiencies and enormous economic losses. This work aims to study the effect of series of synthesized aryl ionic liquids (ILs) containing different alkyl chains, named as R8-IL, R10-IL, R12-IL, and R14-IL, on the onset precipitation point of asphaltene in crude oil. R8-IL, R10-IL, R12-IL, and R14-IL were synthesized with high yields (the yield varied between 82 and 88%) and characterized via different tools of analysis (FTIR, 1H NMR, and Elemental Analysis). Their Thermal Gravimetric Analysis (TGA) was investigated and showed a reasonable degree of stability. It was found that R8-IL (short alkyl chain) has the highest stability, while R14-IL (long alkyl chain) is the lowest one. Quantum chemical calculations were conducted to study the reactivity and geometry of their electronic structures. Moreover, surface and interfacial tension of them were studied. It was found that the efficiency of the surface active parameters increased by increasing the length of the alkyl chain. The ILs were evaluated to delay the onset precipitation point of asphaltene using to different methods; the kinematic viscosity and the refractive index. Results from the two methods showed delaying of onset precipitation after the addition of the prepared ILs. The asphaltene aggregates was dispersed due to the π–π* interactions and hydrogen bonds formation with the ILs.

Effect of linking groups and hydrophobic groups on properties of sulfate Gemini surfactants

From the perspective of molecular design, a series of sulfate Gemini surfactants with different hydrophobic chains and linking groups were synthesized by etherification, ring opening and sulfation. The structures of the products were characterized by IR and 1H NMR. The synthesized sulfate Gemini surfactants had good heat resistance, especially the surfactants with rigid linking groups, measured by thermogravimetric analysis. The synthetic surfactants had low Krafft points, wherein the Krafft points of the surfactants with a carbon chain of 12 were <0 °C. With increasing hydrophobic carbon chain length or decreasing methylene number of linker, their CMC and γcmc first decreased and then increased. The γcmc of surfactants with rigid linking groups were higher and their CMCs were lower. It is analyzed by the calculated surface activity parameters (pC20, Γmax, Amin) that with increasing hydrophobic chain length, the surface activity of synthetic surfactants increased first and then decreased, and the surfactant with hydrophobic carbon chain C14 had the best surface activity. The influences of the length of the linking group and the hydrophobic group on the emulsifying capacity, wetting property, calcium soap dispersion and foam property of the surfactants were also analyzed. It was an attempt to explore and design excellent Gemini surfactants.

Newly synthesized quaternary ammonium bis-cationic surfactant utilized for mitigation of carbon steel acidic corrosion; theoretical and experimental investigations

New quaternary ammonium bis-cationic surfactant namly; 4,4′-(((1Z,5Z)-pentane-1,5-diylidene)bis(azaneylylidene))bis(1-dodecyl-1,5-dimethyl-3-oxo-2-phenyl-2,3-dihydro-1H-pyrazol-1-ium bromide (QABCS) was synthesized and characterized via various spectral techniques. Surface tension measurements were performed for the investigation of surface-active parameters. QABCS's effectiveness as a corrosion inhibitor for carbon steel (CS) in 1.0 M HCl was evaluated using a variety of techniques. Inhibition potency progresses via rising QABCS dose while decreases with the temperature increasing. QABCS boosts the impedance of CS corrosion via 94.67% at 1 × 10−3 M. In addition, QABCS adsorption is consistent with Langmuir dsorption isotherm model. QABCS regards a mixed-type inhibitor. The explanation of density-functional theory (DFT) and Monte Carlo (MC) findings shows that the QABCS compound has a high adsorption potential on CS surface due to active centers in the QABCS' molecular structure. According to the scanning electron microscope (SEM) and atomic force microscope (AFM) findings, QABCS creates a shielding layer over carbon steel substrate. Theoretical discussions, as well as SEM and AFM findings, are compatible with laboratory corrosion assessment studies.

Investigation of the synergistic effect and the morphology of the binary compound systems with potassium N-lauroyl glycinate

Abstract Potassium N-lauroyl glycinate (PLG) is an amino acid surfactant widely used in detergents and has excellent chemical properties. In the present work, PLG was mixed in different molar ratios (α1) with the commonly used amphoteric surfactant lauryl amidopropyl betaine (LAB) or the non-ionic surfactant alkyl glycoside (APG). Subsequently, the surface tension, average hydrodynamic radius and number of micellar aggregates of the individual surfactants and the compound systems were measured using the hanging plate method, dynamic light scattering and fluorescence probe method, respectively, and the corresponding surface activity parameters were calculated. The results show that the binary PLG/LAB and PLG/APG systems exhibit non-ideal behaviour and that there was mutual attraction in the systems. The broad distribution of the micelle radius of the PLG/LAB compound system indicates that there are two types of micelles, namely spherical and rod-shaped in the systems. The distribution of the micelle radius of the PLG/APG compound system decreases to the minimum value at α 1 = 0.5. At α 1 = 0.7 and 0.9, double peaks and a broad distribution were also observed. The number of micelle aggregates in the PLG/LAB and PLG/APG compound systems is less than that of the individual surfactants at the respective mole fractions.

NEW SURFACE-ACTIVE PETROCOLLECTING AND PETRODISPERSING REAGENT BASED ON STEARIC ACID AND TRYETHYLENETETRAAMINE

New surfactant was synthesized from stearic and triethylenetetraamine at room temperature, without utilizing any catalyst or solvent. Structure and composition of the salt was confirmed by using IR-, NMR- and UV- spectroscopies . Surface tension, conductivity measurements were performed on aqueous solutions of new surfactant. Its surface activity and colloidal-chemical parameters such as critical micelle concentration (CMC), surface pressure at CMC (πCMC), surface tension at CMC (γCMC), surface excess (Γmax), concentration required for 20 mN/m reduction of surface tension (C20), Gibbs energies of adsorption and micellization (ΔGad and ΔGmic) were determined. Moreover, corrosion properties and petrocollecting and petrodispersing properties of this salt was determined and maximum values of petrocollecting coefficients was calculated.

Inhibition of Sulfate‐Reducing Bacteria by Para‐amino‐N‐((1‐Alkylpyridin‐1‐Ium Bromide)‐4‐Yl) Benzamide Surfactants and Surfactant‐Coated Silver Nanoparticles

AbstractIn the present work, we report the antibacterial activity of silver nanoparticles (AgNP) coated with the surfactants para‐amino‐N‐((1‐decylpyridin‐1‐ium bromide)‐4‐yl) benzamide and para‐amino‐N‐((1‐dodecylpyridin‐1‐ium bromide)‐4‐yl) benzamide (P10 and P12, respectively). P10 and P12‐coated AgNP were stable, as confirmed by ultraviolet–visible spectrophotometry, transmission electron microscopy, and other surface activity parameters. Both P10 and P12 and the coated AgNP formulations were investigated for their activity against sulfate reducing bacteria (SRB). Overall, our results showed the importance of coating AgNP with surfactants (P10 and P12) in the design and development of new biocides against SRB.

Study of Steel Electro-dissolution Behavior in Presence of Some Surfactants. Electrochemical Investigation and Surface Active Properties Determination

Steel electro-dissolution performance was investigated in orthophosphoric acid in the presence of N-oleyl 1.3 diaminopropane, Benzalkounuim chloride, Soduim lauryl sulphate and Di-Isononyl phthalate as a surfactant using potentiodynamic polarization measurements. The retardation performance of these surfactants was examined. The surfactant surface active parameters were estimated based on surface tension measurements. The parameters calculated comprise the critical micelle concentration (CMC), maximum surface excess (Гmax), minimum surface area (Amin) and effectiveness (πCMC). The micellization thermodynamic parameters (ΔGmic, ΔSmic) for the estimated surfactants were also computed. Results obtained from surface active properties are comparable with those gained from galvanostatic polarization measurements. Temperature influence on the steel dissolution performance was examined at 25 to 40oC range. Steel kinetic study in orthophosphoric acid- free solution and orthophosphoric acid containing surfactant was also examined. The dissolution kinetic and activated parameters were computed. Results based on microscopy measurement indicate that, addition of new four surfactants, resulting in the solution shows potential, a discrete progress in the metal texture was monitored. Improvement produced in electro-polishing bath by the investigated SAS that owing to the adsorption of such surface active agents on the anode surface.

Synthesis and surface activity of novel high energy nitrate surfactants

A series of single hydrophobic chain high-energy surfactants with a nitrate group and an alkyl chain length of between C8 and C14 were synthesized using novel approaches. The structures of the obtained compounds were characterized by 1H-NMR, 13C-NMR, MS and IR spectroscopies. In addition, the physical and chemical properties of these high-energy surfactants were measured by the surface tension method and their principal surface activity parameters such as cmc, γ cmc, pC20, cmc/C20, Γ max, and A min were determined. This article provides an elaborate discussion of the characteristics of the surface activity parameters and thermal stability that change with increasing length of the hydrophobic chains. For these high-energy surfactants, experiments have shown that longer hydrophobic chain leads to better surface activity, while slightly reducing thermal stability.

Influence of sodium bis(2-ethylhexyl) sulfosuccinate on the self-assembly of AOT based surface-active ionic liquids having different pharmacologically active cations in the aqueous medium

The aggregation behavior of three AOT based ionic liquids have been investigated in aqueous medium in the presence of different concentrations i.e. (0.04, 0.08, 0.12, 0.16) mM of sodium bis(2-ethylhexyl) sulfosuccinate (NaAOT) at different temperatures (298.15, 308.15, 318.15) K. The AOT based ionic liquids have been successfully synthesized by replacing the cation of sodium bis(2-ethylhexyl) sulfosuccinate (NaAOT) with various pharmacologically active cations such as cholinium [Cho]+, tetraethylammonium [TEA]+, and tetrabutylammonium [TBA]+. The conductivity and surface tension measurements have been employed to understand their aggregation behavior by evaluating various thermodynamic and surface-active parameters such as standard free energy of micellization (ΔGm0), standard enthalpy of micellization (ΔHm0), standard entropy of micellization (ΔSm0), surface pressure at cmc(á́¨cmc), maximum surface excess concentration (Γmax), the minimum area of surfactant monomer at the air/water interface (Amin), the standard Gibbs free energy of adsorption (ΔGad0) and the free energy of a surface at equilibrium (Gmins).