Alkyl Chain Length Of Ionic Liquids Research Articles

The Physics of Antimicrobial Activity of Ionic Liquids.

The bactericidal potency of ionic liquids (ILs) is well-established, yet their precise mechanism of action remains elusive. Here, we show evidence that the bactericidal action of ILs primarily involves the permeabilization of the bacterial cell membrane. Our findings reveal that ILs exert their effects by directly interacting with the lipid bilayer and enhancing the membrane dynamics. Lateral lipid diffusion is accelerated, which in turn augments membrane permeability, ultimately leading to bacterial death. Furthermore, our results establish a significant connection: an increase in the alkyl chain length of ILs correlates with a notable enhancement in both lipid lateral diffusion and antimicrobial potency. This underscores a compelling correlation between membrane dynamics and antimicrobial effectiveness, providing valuable insights for the rational design and optimization of IL-based antimicrobial agents in healthcare applications.

Synergistic interactions of ionic liquids and antimicrobials improve drug efficacy.

SummaryCombinations of ionic liquids (ILs) with antimicrobial compounds have been shown to produce synergistic activities in model liposomes. In this study, imidazolium chloride-based ILs with alkyl tail length variations are combined with commercially available, small-molecule antimicrobials to examine the potential for combinatorial and synergistic antimicrobial effects on P. aeruginosa, E. coli, S. aureus, and S. cerevisiae. The effects of these treatments in a human cell culture model indicate the cytotoxic limits of ILs paired with antimicrobials. The analysis of these ILs demonstrates that the length of the alkyl chain on the IL molecule is proportional to both antimicrobial activity and cytotoxicity. Moreover, the ILs which exhibit synergy with small-molecule antibiotics appear to be acting in a membrane permeabilizing manner. Collectively, results from these experiments demonstrate an increase in antimicrobial efficacy with specific IL + antimicrobial combinations on microbial cultures while maintaining low cytotoxicity in a mammalian cell culture model.

Alkyl chain length affecting uptake of imidazolium based ionic liquids by ryegrass (Lolium perenne L.)

Imidazolium based ionic liquids (ILs) have been extensively used in the various industrial fields, however, the dependence of their structure on toxicity and bioavailability by plants is not clear. Thus, in this study, uptake of imidazolium based ILs with different alkyl chain lengths (e.g., [C2mim]+ and [C8mim]+) by ryegrass and their toxicity to plant growth were investigated. Results show that the two ILs could be removed by ryegrass with high efficiencies, and a higher uptake efficiency and accumulation was observed for [C2mim]+ with shorter chain length compared with that for [C8mim]+. A higher growth inhibition of ryegrass by [C8mim]+ was observed compared with that by [C2mim]+, indicating the long alkyl chain length of ILs had a negative effect on the plant growth. ILs taken up by ryegrass was retained in the roots and their translocation from roots to shoots was restricted. The IL concentration in roots was 0.68 mg/g-fresh weight for [C2mim]+ and 0.08 mg/g- fresh weight for [C8mim]+ when the ryegrass was exposed to 10 mg/L ILs. This study proved that plant assimilation of ILs depended on their alky chain lengths, which would be useful for understanding the fate of ILs with various structures in phytoremediation for ILs-contaminated water.

Interactions of alkyltriphenyl phosphonium based ionic liquids with block copolymer microstructures: A multitechnique study

Here we report comprehensive analysis on the influence of different alkyltriphenyl phosphonium (CnTPPBr) (with varying alkyl chain lengths) based cationic surfactants displaying analogical characteristics to ionic liquids (IL) on the physicochemical properties of an ethylene oxide–propylene oxide (EO–PO) triblock copolymer, Pluronic®, P103 (EO17-PO60-EO17; M. Wt-3250) using several techniques viz. cloud point (CP), viscosity, small angle neutron scattering (SANS), dynamic light scattering (DLS) and high sensitivity differential scanning calorimetry (HSDSC). The CP results indicate notable increase in values with the increase in alkyl chain length of IL. A significant decrease in the micelle size was witnessed from the DLS and SANS results. The presence of sodium bromide (NaBr), however, counteracted the disruptive effect of ILs and promoted micellar growth. The critical micelle temperature (CMT) results attained using HSDSC are also reported. The information acquired from the present study will be highly beneficial in understanding the behavior of Pluronic® micelles in the presence of CnTPPBr ILs and for their effective utilization in various industrial applications.

Effects of Ionic Liquid Alkyl Chain Length on Denaturation of Myoglobin by Anionic, Cationic, and Zwitterionic Detergents

The unique electrochemical properties of ionic liquids (ILs) have motivated their use as solvents for organic synthesis and green energy applications. More recently, their potential in pharmaceutical chemistry has prompted investigation into their effects on biomolecules. There is evidence that some ILs can destabilize proteins via a detergent-like manner; however, the mechanism still remains unknown. Our hypothesis is that if ILs are denaturing proteins via a detergent-like mechanism, detergent-mediated protein unfolding should be enhanced in the presence of ILs. The properties of myoglobin was examined in the presence of a zwitterionic (N,N-dimethyl-N-dodecylglycine betaine (Empigen BB®, EBB)), cationic (tetradecyltrimethylammonium bromide (TTAB)), and anionic (sodium dodecyl sulfate (SDS)) detergent as well as ILs based on alkylated imidazolium chlorides. Protein structure was measured through a combination of absorbance, fluorescence, and circular dichroism (CD) spectroscopy: absorbance and CD were used to monitor heme complexation to myoglobin, and tryptophan fluorescence quenching was used as an indicator for heme dissociation. Notably, the detergents tested did not fully denature the protein but instead resulted in loss of the heme group. At low IL concentrations, heme dissociation remained a traditional, cooperative process; at high concentrations, ILs with increased detergent-like character exhibited a more complex pattern, which is most likely attributable to micellization of the ionic liquids or direct denaturation or heme dissociation induced by the ILs. These trends were consistent across all species of detergents. 1,6-diphenyl-1,3,5-hexatriene (DPH) fluorescence was further used to characterize micelle formation in aqueous solutions containing detergent and ionic liquid. The dissociation thermodynamics show that EBB- and TTAB-induced dissociation of heme is not significantly impacted by room temperature ionic liquids (RTILs), whereas SDS-induced dissociation is more dramatically impacted by all RTILs examined. Together, these results indicate a complex interaction of detergents, likely based on headgroup charge, and the active component of RTILs to influence heme dissociation and potentially protein denaturation.

Thermodynamic Parameters and Solvation Behavior of 1-Ethyle-3-methylimidazolium Tetrafluoroborate and 1-Butyl-3-methylimidazolium Tetrafluoroborate in N,N-Dimethylformamide and Acetonitrile at Different Temperature

The present paper investigations made on the ion-solvation interaction of new class of salts ionic liquids (IL) such as 1-Ethyle-3-methylimidazolium Tetrafluoroborate and 1-Butyl-3-methylimidazolium Tetrafluoroborate in N,N-Dimethylformamide and Acetonitrile at temperature range of 283.15 to 318.15K with the aid of using electrical conductivity precept. The electrical conductance data were analyzed with the aid of Fuoss – Justice equation of conductivity. The molar conductance (Λ), the limiting molar conductance (Λ0), the association constants (KA), the Walden product (Λ0 η0), The Eyring activation energy of charge transport (ΔH‡λ) and the standard thermodynamic parameters of association (〖∆G〗_A^o, 〖∆H〗_A^oand 〖∆S〗_A^o) were calculated and mentioned. The results show that, the molar conductance and the limiting molar conductance values have been diminished as the relative permittivity of the solvent lowered at the same time, the association constant increased. Additionally, the outcome exhibit that the values of the molar conductance, and the limiting molar conductance were increased as the temperature increased at the same time, the association constant increased indicating that the association process is an endothermic one as indicated from 〖∆H〗_A^o value. The effect of the alkyl chain length of IL is clear on the thermodynamic parameters and association properties.

Effect of Imidazolium-Based Ionic Liquids on the Structure and Phase Behavior of Palmitoyl-oleoyl-phosphatidylethanolamine.

Among various applications, ionic liquids (ILs) have been used as antimicrobial agents in laboratories, possibly through induction of the leakage of bacteria. A molecular-level understanding of the mechanism that describes how ILs enhance the permeation of membranes is still lacking. In this study, the effects of imidazolium-based ILs with different alky chain lengths on the structure and phase behavior of 1-palmitoyl-2-oleoyl-phosphatidylethanolamine (POPE), which is a representative bacteria-membrane-rich lipid, have been investigated. By employing differential scanning calorimetry and synchrotron small- and wide-angle X-ray scattering techniques, we found that ILs with longer alkyl chains influenced the phase behavior more effectively, and lower IL concentrations are needed to induce phase separation for both lamellar liquid crystalline phase and nonlamellar inverted hexagonal phase of POPE. Interestingly, the IL with an alkyl chain of 12 carbon atoms ([C12mim]Cl) shows a difference. It exhibits a stronger disturbing effect on the POPE bilayer structure than [C16mim]Cl, indicating that the ability of ILs to influence the membrane structures is dependent not only on the alkyl chain length of ILs, but also on the degree of matching of the alkyl chain lengths of ILs and lipids. The new lamellar and nonlamellar structures induced by ILs both have smaller repeat distances than that of pure POPE, implying thinner membrane structures. Data of the fluorescence-based vesicle dye leakage assay are consistent with these results, particularly the defects caused by IL-induced phase separation can enhance the membrane permeability markedly. The present work may shed light on our understanding of the antimicrobial mechanism of ILs.

Dissolution of cellulose in novel carboxylate-based ionic liquids and dimethyl sulfoxide mixed solvents

A series of substituted piperazinium, piperidinium, and pyrrolidinium acetates were synthesized. Highly effective cellulose solvents have been designed by mixing an aprotic polar solvent, dimethyl sulfoxide (DMSO), with synthesized ionic liquids (ILs). Different weight ratios of corresponding IL/DMSO mixed solvents were prepared to investigate the effect of cosolvent on cellulose solubility. Cellulose solubility in IL/DMSO solvent systems was measured at 25, 50 and, 80 °C. The effect of factors such as solvent composition, process temperature, type of IL’s cation, and alkyl chain length of IL’s cation on cellulose solubility was investigated. Amongst all tested solvents, N,N’-dimethyl-N-ethylpiperazinium acetate ([DMEPpz][Ac]/DMSO) mixed solvent exhibits the best performance in the dissolution of cellulose, reaching up to 13.5 wt% at 80 °C. The dissolved cellulose was regenerated using water as an antisolvent. The structure and morphology of the regenerated cellulose material were characterized by SEM, XRD, and FTIR, respectively.

Isolation of C-phycocyanin from Spirulina platensis microalga using Ionic liquid based aqueous two-phase system

An aqueous two-phase system (ATPS) with ionic liquids (ILs) was used for the isolate of C-phycocyanin (CPC) from Spirulina platensis microalga. Various imidazolium ILs and potassium salts were studied. The effect of ILs-ATPS on the extraction efficiency of CPC was also studied. The experimental parameters like pH, loading volume, algae concentration, temperature, and alkyl chain length of IL were well-covered in this report. The experimental results showed that the extraction efficiency, the partition coefficient, and the separation factor for CPC were 99%, 36.6, and 5.8, respectively, for an optimal pH value of 7 and a temperature of 308 K. The order of extraction efficiency for CPC using IL-ATPS was: 1-octyl-3-methylimidazolium bromide (C8MIM-Br) > 1-hexyl-3-methylimidazolium bromide (C6MIM-Br) > 1-butyl-3-methylimidazolium bromide (C4MIM-Br). The isolation process followed the pseudo second-order kinetic model and the thermodynamic results were obviously spontaneous.

Synthesis, self-assembly and micellization characteristics of choline alkanoate ionic liquids in association with a star block copolymer

Herein, alkyl chain dependent self-assembly of choline carboxylate ionic liquids (ILs) and their effect on micellar characteristics of a star block copolymer (Tetronic®T1304) are reported. The ILs showed good aqueous solubility (low Kraft point) and formed spherical micelles. Small angle neutron scattering (SANS) analyses revealed a reduction in the critical micelle concentration (CMC) and elevation in the aggregation number (Nagg) upon increasing alkyl chain length of ILs. More importantly, ILs demonstrated good biocompatibility in murine erythrocytes and A549 cells, irrespective of the chain length.Furthermore, the effect of IL addition on micellar behaviour of T1304 was examined through thermal and scattering studies. We observed alkyl chain dependent increase in the cloud point (CP), critical micellization temperature (CMT), micelle size (Rh, Rc, Rhs) and Nagg. In association with T1304, long chain ILs (n = C12–C18) formed charged mixed micelles with a lower Nagg which showed enhanced solubilization of quercetin, a hydrophobic drug. Mixed micelles, composed with such biocompatible ILs, can further be tuned to explore their drug delivery applications.

Deciphering interactions of ionic liquids with biomembrane.

Ionic liquids (ILs) are a special class of low-temperature (typically < 100°C) molten salts, which have huge upsurge interest in the field of chemical synthesis, catalysis, electrochemistry, pharmacology, and biotechnology, mainly due to their highly tunable nature and exceptional properties. However, practical uses of ILs are restricted mainly due to their adverse actions on organisms. Understanding interactions of ILs with biomembrane is prerequisite to assimilate the actions of these ionic compounds on the organism. Here, we review different biophysical methods to characterize interactions between ILs and phospholipid membrane, a model biomembrane. All these studies indicate that ILs interact profoundly with the lipid bilayer and modulate the structure, microscopic dynamics, and phase behavior of the membrane, which could be the fundamental cause of the observed toxicity of ILs. Effects of ILs on the membrane are found to be strongly dependent on the lipophilicity of the IL and are found to increase with the alkyl chain length of IL. This can be correlated with the observed higher toxicity of IL with the longer alkyl chain length. These informations would be useful to tune the toxicity of IL which is required in designing environment-friendly nontoxic solvents of the so-called green chemistry for various practical applications.

Evaluation of anion chain length impact on aqueous two phase systems formed by carboxylate anion functionalized ionic liquids

Abstract Aqueous biphasic systems (ABS) based on ionic liquids (ILs) are considered as promising separation and extraction media for replacing conventional extraction systems consisting of volatile organic solvents. In the present work, set of ILs consisting of tetrabutylammonium cation and carboxylate anions were synthesised and studied for their ability to form ABS in presence of strong salting-out agent K3PO4 at 298.15 K and atmospheric pressure. The influence of alkyl chain length of ILs’ anions on the phase splitting ability has been systematically investigated. Experimentally determined binodal curve data has been fitted to Merchuk’s equation and corresponding fitting parameters have also been determined. Further, selected ternary systems have been analysed for their extraction efficiencies for an amino acid, Tryptophan. Solvatochromic parameters of aqueous solutions of ILs have been determined to further scrutinize their influence on extraction efficiencies of studied ABS. The results indicated that phase behaviour and extraction efficiencies are governed by multiple factors prevailing at microscopic level like hydrophobicity, hydrogen bond accepting ability etc. The combination of suitable cation and anion entities of ILs, in turn, decides the dominant physical phenomenon and consequent phase behaviour and extraction aptitudes. In addition, this work addresses the effect of temperature on ABS formation and temperature dependence similar to that of ABS consisting of polymers and inorganic salts have been observed. This work gives insights into multifaceted effects of longer alkyl chains of IL’s anion on phase behaviour and extraction aptitudes of IL based ABS.

Influence of Imidazolium Ionic Liquids on the Interactions of Human Hemoglobin with DyCl3, ErCl3, and YbCl3 in Aqueous Citric Acid at T = (298.15, 303.15, and 308.15) K and 0.1 MPa

Density, sound velocity, viscosity, surface tension, and molar conductivity for DyCl3·6H2O, ErCl3·6H2O, and YbCl3·6H2O from (0.002 to 0.012) mol·kg–1 in aqueous solutions of (a) citric acid (0.005 mol·kg–1) (b) citric acid + human hemoglobin (1 g·kg–1) and (c) citric acid + human hemoglobin +1-alkyl-3-methylimidazolium chloride (0.001 mol·kg–1) ([RMIMCl], R = ethyl, butyl, and hexyl) at T = (298.15, 303.15, and 308.15) K and 0.1 MPa are reported. Densities were used to calculate the apparent molar volumes. The viscosity data are analyzed and interpreted using the extended Jones–Dole equation for lanthanide chloride to calculate viscosity A- and B-coefficient values. The varying trends of the aforesaid physicochemical parameters have been interpreted in terms of the solute–solute and solute–solvent interactions. An attempt has been made to investigate the influence of ionic liquid alkyl chain length on the interacting activities of lanthanide chloride with citric acid and the critical role being played by ...

Controllable synthesis of nitrogen-doped hollow mesoporous carbon spheres using ionic liquids as template for supercapacitors

We have demonstrated a facile and controllable synthesis of monodispersed nitrogen-doped hollow mesoporous carbon spheres (N-HMCSs) using resorcinol/formaldehyde resin as a carbon precursor, tetraethyl orthosilicate as a structure-assistant agent, ionic liquids (ILs) as soft template, partial carbon sources, and nitrogen sources. The sizes and the architectures including hollow and yolk-shell of resultant carbon spheres can be efficiently controlled through the adjustment of the content of ILs. Alkyl chain length of the ILs also has an important effect on the formation of N-HMCSs. With proper alkyl chain length and content of ILs, the resultant N-HMCSs show monodispersed hollow spheres with high surface areas (up to 1158m2g−1), large pore volumes (up to 1.70cm3g−1), and uniform mesopore size (5.0nm). Combining the hollow mesoporous structure, high porosity, large surface area, and nitrogen functionality, the as-synthesized N-HMCSs have good supercapacitor performance with good capacitance (up to 159Fg−1) and favorable capacitance retention (88% capacitive retention after 5000 cycles).

A study of the molecular interactions between ammonium-based ionic liquids and N,N-dimethylacetamide

In this work, we report the molecular interactions of different cation alkyl chain lengths with same anion of ammonium-based ionic liquids (ILs) such as tetraethylammonium hydroxide (TEAH), tetrapropylammonium hydroxide (TPAH) and tetrabutylammonium hydroxide (TBAH) with N,N-dimethylacetamide (DMA) through thermophysical properties with varying the compositions of ILs at different temperatures from 25 to 40°C under atmospheric pressure. Experimental densities (ρ), ultrasonic sound velocities (u), viscosities (η) and refractive indices (nD) of binary mixtures of ILs with DMA are measured over the wide composition range. The excess molar volumes (VE), deviation in isentropic compressibilities (Δκs), deviation in viscosities (Δη) and deviation in refractive indices (ΔnD) are calculated from experimental values and are correlated by Redlich-Kister polynomial equations. Consequently, VE values show that negative for small cation alkyl chain length of ammonium-based ILs as compared to large cation alkyl chain length of ILs. We have observed the strength of intermolecular interactions such as hydrogen bonding, ion-ion pair interactions and induced dipole interactions between the ions of ammonium-based ILs with DMA from obtained data. Thermophysical properties, however, possessed by these binary systems are exceedingly promising and predictable that these systems will find applications in chemical industry.

Liquid–liquid equilibria of aqueous biphasic systems of ionic liquids and dipotassium hydrogen phosphate at different temperatures: Experimental study and thermodynamic modeling

The phase diagrams of the {1-butyl-3-methylimidazolium nitrate ([Bmim][NO3])/1-hexyl-3-methylimidazolium nitrate ([Hmim][NO3])+dipotassium hydrogen phosphate (K2HPO4)}c aqueous biphasic systems (ABS) and the binodal curves of {1-octyl-3-methylimidazolium nitrate ([Omim][NO3])+K2HPO4} ABS have been determined experimentally at T=(288.15, 298.15, and 308.15) K. The Merchuk equation with three dependent-temperature adjustable parameters was used for reproducing and predicting the binodal curves. The effect of the alkyl chain length of ionic liquids (ILs) was studied. It was found that the two-phase formation in the investigated ABS is decreased with decreasing the alkyl chain length of IL in the order: [Hmim][NO3]>[Omim][NO3]>[Bmim][NO3]. Moreover, the effect of temperature on the binodal curves and tie-lines was also discussed. It was shown that the biphasic region expanded with a decrease in temperature, whereas the absolute value of slope of the tie-lines slightly decreased with an increase in temperature. Finally, the liquid–liquid equilibrium (LLE) data for the studied systems are correlated by using the NRTL thermodynamic model, and good agreement was obtained between the correlation and the experimental data.

Standard partial molar volumes and viscosity B-coefficients of ionic liquids [Cnmim]Br (n = 4, 6, 8) in alcohols at 298.15 K

Volume and viscosity data of ionic liquid (IL)-molecular solvent mixtures are very important for the design of process engineering involving these mixtures. In this work, densities and viscosities for the binary solutions of [Cnmim]Br (n=4, 6, 8) ionic liquids with methanol, 1-propanol, and 1-pentanol have been determined at 298.15K as a function of IL concentrations. From these experimental data, apparent molar volumes, standard partial molar volumes, and viscosity B-coefficient of ILs were derived. The effect of the alkyl chain length in the imidazolium cation and properties of alcohol on the standard partial molar volumes of ILs and viscosity B-coefficient was discussed. In a given alcohol, the standard partial molar volumes of ILs and viscosity B-coefficient increase linearly with increasing alkyl chain length of ILs. For a given IL, unexpectedly, its standard partial molar volume in the three molecular solvents is not a constant, but increases in the order: 1-pentanol>1-propanol>methanol. The viscosity B-coefficients of a given IL in the alcohols also change in the same sequential order. These results suggest that the interactions between ILs and the alcohols increase with the decrease of alkyl chain length of the alcohols.

Elucidation of the Channel Activities of Gramicidin a in the Presence of Ionic Liquids (ILS) using Model Cell Membranes

Ionic liquid(IL) is a salt in the liquid state below 100°C and have been considered as eco-friendly solvent that can replace organic solvent due to their unique properties; non-volatility and non-explosiveness. However, the safety of ILs in aquatic environment has not been fully assessed. In this work, we investigated the effects of ILs on ion channels when they are incorporated into a lipid bilayer. We chose gramicidin A (gA) as our model protein that selectively permeates cations. The ion permeability of gA varies depending on the type of ILs. In order to measure channel activities of gAs, we used two methods; fluorescence assay utilizing using stop-flow spectrometer and measurement of ion currents across lipid bilayers using a patch clamp instrument. Furthermore, we revealed that alkyl chain length of ILs and ion strength of buffer play important roles in ion permeability and confirmed how electrostatic effects due to charges on the membrane surface changed depending on ion strength of buffer using MD simulation. As a result, we should be able to design safer ILs by taking our results into account.

Effect of the alkyl chain length of a hydrophobic ionic liquid (IL) as an oil phase on the phase behavior and the microstructure of H2O/IL/nonionic polyoxyethylene surfactant ternary systems

The use of hydrophobic ionic liquids (ILs) as oil phases to formulate a H2O-in-IL (W/IL) microemulsion is of great significance to enzyme catalysis. In this report, we present the essential influence of the alkyl chain length of ILs on the phase behavior and the microstructure of H2O/IL/CnEm (polyoxyethylene alkyl ether) ternary systems. The ILs are [C4mim][PF6] (1-butyl-3-methylimidazolium hexafluorophosphate) and [C8mim][PF6] (1-octyl-3-methylimidazolium hexafluorophosphate). For a given nonionic surfactant, the alkyl chain length of ILs has an influence on the water solubilization capacity. The difference in the capacity, however, narrows and even disappears upon significant increase of the hydrophilic chain length of CnEm. FTIR spectroscopy and UV-Vis spectroscopy confirm the existence of bulk water in both [C4mim][PF6]- and [C8mim][PF6]-based C12E23-stabilized W/IL microemulsions. The catalytic activity of laccase hosted in the W/IL microemulsion and the dynamic light scattering measurement reveal that under the same conditions, the water droplet size dispersed in [C4mim][PF6] is larger than that in [C8mim][PF6]. To establish the newly developed W/IL microemulsion as an effective medium for laccase, a control study is presented, demonstrating that the W/IL microemulsion is superior to the pure ILs for the expression of the catalytic activity of laccase.

Self-aggregation of cationic dimeric surfactants in water–ionic liquid binary mixtures

The micellization of four dimeric cationic surfactants (“gemini surfactants”) derived from N-dodecyl-N,N,N-trimethylammonium chloride was studied in pure water and in water–ionic liquid (IL) solutions by a wide range of techniques. The dimeric surfactants are distinguished by their rigid spacer groups separating the two surfactant motifs, which range from C3 to C5 in length. In order to minimize organic ion pairing effects as well as the role of the ionic liquids as potential co-surfactants, ILs with inorganic hydrophilic anions and organic cations of limited hydrophobicity were chosen, namely ethyl, butyl, and hexyl-3-imidazolium chlorides. 1H NMR two-dimensional, 2D, rotating frame nuclear Overhauser effect spectroscopy measurements, ROESY, supported this premise. The spacer nature hardly affects the micellization process, neither in water nor in water–IL solutions. However, it does influence the tendency of the dimeric surfactants to form elongated micelles when surfactant concentration increases. In order to have a better understanding of the ternary water–IL surfactant systems, the micellization of the surfactants was also studied in aqueous NaCl solutions, in water–ethylene glycol and in water–formamide binary mixtures. The combined results show that the ionic liquids play a double role in the mixed systems, operating simultaneously as background electrolytes and as polar organic solvents. The IL role as organic co-solvent becomes more dominant when its concentration increases, and when the IL alkyl chain length augments.