Dodecyl Ether Research Articles

Nonionic Surfactants for the Cleaning of Works of Art: Insights on Acrylic Polymer Films Dewetting and Artificial Soil Removal

The use of nanostructured fluids (NSFs), that is, micellar solutions and microemulsions, in art conservation is often associated with cleaning purposes as the removal of polymeric coatings and/or soil from artistic surfaces. In both cases, the use of NSFs grants significant improvements over the use of traditional cleaning techniques that employ neat unconfined organic solvents, water, or aqueous solutions. The study of the nature and properties of surfactants present in NSF formulations is important to boost the effectiveness of these systems in applicative contexts and in the search of innovative and highly performing amphiphiles. This work reports on the methoxy-pentadeca(oxyethylene) dodecanoate (MPD) surfactant in two different NSFs, whose utilization in conservation of cultural heritage is new. Its effectiveness is compared to the conventional nonionic amphiphiles used in conservation practice, as pentadeca(oxyethylene) dodecyl ether, for the cleaning of poly(ethyl methacrylate/methyl acrylate) 70:30, p(EMA/MA), and artificially soiled surfaces. The mechanism, through which NSFs interact with polymeric coatings or soiled surfaces, was investigated by confocal laser scanning microscopy, fluorescence correlation spectroscopy, photographic observation, contact angle, surface tension measurements, and small-angle X-ray scattering. The results highlighted the superior MPD’s performance, both in inducing polymer removal and in detaching the soil from coated surfaces. At the microscale, the cleaning involves dewetting-like processes, where the polymer or the soil oily phase is detached from the surface and coalesce into separated droplets. This can be accounted by considering the different surface tensions and the different adsorption mechanisms of MPD with respect to ordinary nonionic surfactants (likely due to the methyl capping of the polar head chain and to the presence of the ester group between the hydrophilic and hydrophobic parts of the MPD surfactant molecule), showing how a tiny change in the surfactant architecture can lead to important differences in the cleaning capacity. Overall, this paper provides a detailed description of the mechanism and the kinetics involved in the NSFs cleaning process, opening new perspectives on simple formulations that are able to target at a specific substance to be removed. This is of utmost importance in the conservation of irreplaceable works of art.

Inhibitory Effect of Hybrid Liposomes on the Growth of NP2 Glioma Cells

The inhibitory activity of hybrid liposomes (HLs), composed of 90 mol% L-α-dimyristoyl-phosphatidylcholine (DMPC) and 10 mol% polyoxyethylene (25) dodecyl ether (C12(EO)25), was investigated in human glioma NP2 cells. HLs with a hydrodynamic diameter below 100 nm persisted for 4 weeks. The inhibitory effect of HLs on the proliferation of NP2 cells was evaluated. Induction of apoptosis in NP2 cells treated with HL was measured through a PI assay and the TUNEL method. HLs caused apoptosis in NP2 cells through the mitochondrial pathway. An increase of AIF protein expression was observed in HL-treated cells. Cellular membrane fluidity of NP2 cells was also increased as revealed by the fluorescence depolarization method. Enhanced HL accumulation in the membrane of NP2 cells was observed.

Improvement of Foaming Ability of Surfactant Solutions by Water-Soluble Polymers: Experiment and Molecular Dynamics Simulation.

Aqueous foam is widely used in fire extinguishing and dust suppression technologies. Improving the foaming ability is the key to reducing the added concentration of foaming agents as well as the economic cost. In this work, the effect of a water-soluble polymer (polyvinyl alcohol, PVA) on the foaming ability of anionic surfactant (sodium dodecyl ether sulfate, SDES) was studied by an experiment and molecular dynamics simulation. The experimental results showed that PVA greatly improves the foaming ability of SDES solutions when the surfactant concentration is less than 0.1%, which is attributed to the fact that the polymer can enhance the stability of bubble films and reduce the bubble rupture rate during the foam generation process. The simulation results indicate that PVA can enhance the hydration of surfactant head groups and contribute to the formation of a three-dimensional hydrogen bond network between surfactants, polymers, and water molecules, thus greatly improving the stability of bubble liquid films. The above results suggest that water-soluble polymers can be used to improve the foaming ability of surfactant solutions by enhancing the bubble film stability, which is beneficial as it reduces the added concentration of foaming agents in aqueous foam applications.

Inhibition of insulin fibrillation by amphiphilic sulfonatocalixarene

Insulin fibrillation poses a variety of problems in biomedical and biotechnological applications of insulin. Inhibiting insulin fibrillation is highly on demand to address those problems. We herein demonstrate the capability of amphiphilic sulfonatocalixarene to inhibit insulin fibrillation. The amphiphilic assembly of p-sulfonatocalix[4]arene tetra dodecyl ether exhibits much better efficiency on inhibiting insulin fibrillation, with respect to p-sulfonatocalix[4]arene and sodium dodecyl benzenesulphonate. The pronounced inhibition effect results from both the preorganized scaffold of calixarene and the amphiphilic assembly.

Sensitivity of Extracellular Vesicles from Human Blood Serum to Various Detergents

Blood exosomes and microvesicles, collectively known as small extracellular vesicles (sEV), are vesicles about 100-150 nm in size. Small EV are involved in various aspects of signaling in the body; in addition, they can serve as markers of various pathologies. For biochemical studies, vesicle solubilization is often required. We tested the ability of various detergents to dissolve membranes of the sEV. Small EV were isolated from the blood serum of healthy volunteers by gel filtration on Sepharose CL-2B and tried to solubilize them using the anionic detergent DOC (sodium deoxycholate), non-ionic detergent Brij 35 (polyoxyethyleneglycol dodecyl ether), zwitterionic detergent CHAPS (3 - [(3-chloramidopropyl) dimethylammonio] -1-propanesulfonate), and cationic detergent CTAB (cetyl trimethylammonium bromide). The concentration of sEV in the solution was determined by dynamic light scattering. We find DOC is the most effective for sEV solubilization.

A Comprehensive Review of Sheep and Goat Pox Viruses: Perspective of Their Epidemiology and Economic Importance in Egypt

ruminant animals. It is characterized by fever, anorexia, depression, inflammation of the mucous membranes of the eyes and nose, respiratory distress with appearance of pox lesions on areas devoid of wool and hair such as checks, lips, nostrils, inner aspect of the thigh and beneath the tail, also the size of superficial lymph nodes was larger than normal. The objective of this article was to review the epidemiology and economic importance of sheep and goat pox. The causative agent of Sheep and goat pox is SGPV of Subfamily, Chordopoxvirinae, family Poxoviridae, genus Capripoxvirus. SGPV has worldwide distribution and endemic throughout southwest and central Asia, northern and central Africa, and Middle East countries including Egypt. SGPV produce unusual economic loss due to high morbidity, mortality rate, reduction in milk and meat production, abortions, poor wool and skin quality and as a result of trade restrictions. Survival of SGPV in external environment may reach about 6 months. The virus inactivated by sun light and heat, sensitive to detergents as sodium dodecyl sulphate and ether 20%, chloroform and formalin 1%. The diseases are more severe in young animals than adults with mortalities up to 100%. Control of the disease depends on early detection and notification, restriction of animals’ movement, culling of affected and in-contact animals, and ring vaccination with inactivated vaccine.

Highly efficient degradation of 2,2′,4,4′-tetrabromodiphenyl ether through combining surfactant-assisted Zn0 reduction with subsequent Fenton oxidation

2,2′,4,4′-tetrabromodiphenyl ether (BDE47) was difficult to be rapidly degraded by common reductive debromination or oxidative decomposition. In this study, the debromination via surfactant-assisted zero valent zinc (Zn0) reduction and subsequent Fenton oxidation was combined to completely degrade BDE47. Firstly, Zn0 integrated with surfactants including cetyltrimethylammonium chloride (CTAC), polyethylene glycol dodecyl ether (Brij35), or 1-dodecanesulfonic acid sodium salt (SDS) were evaluated for their reactivity to debrominate BDE47. CTAC-assisted Zn0 system presented the highest removal efficiency of 98.6% for BDE47 (C0 = 5 mg/L) under the optimized conditions including 0.3 g/L of Zn0 particles and 0.05 g/L of CTAC at 25 °C and pH 4.0 during 1-h reaction. Subsequently, the debromination products as low-brominated BDEs were attacked by hydroxyl radicals (•OH) from Fenton reagent, which were decomposed into short-chain carboxylic acids and even mineralized within 2-h oxidation. In addition, HPLC, GC–MS, LC–MS/MS, and IC were employed to detect intermediates during this reaction/oxidation process and the pathways of debromination and oxidation were proposed according to carbon and bromine balance. The above combination achieved the complete degradation of BDE47 via a relative low-cost method to rapidly remove PBDEs, which provide a new approach for the effective treatment of halogenated organic pollutants.

Self-Assembly of Amphiphilic Amylose Derivatives in Aqueous Media.

Six amylose derivative (C12CMA) samples with hydrophobic dodecyl ether groups and hydrophilic sodium carboxymethyl groups were synthesized from an enzymatically synthesized amylose for which the weight-average molar mass is 50 kg mol-1 to realize amylose-based amphiphilic polymer micelles. The degree of substitution of hydrophobic (DSC12) and hydrophilic (DSCM) groups ranges between 0.076 and 0.39 and between 0.35 and 1.83, respectively. Static and dynamic light scattering, small-angle X-ray scattering (SAXS), and fluorescence measurements with pyrene as a probe were carried out for the samples in 150 mM aqueous NaCl to characterize the higher-order structure in solution. The fluorescence from pyrene showed that all six samples have hydrophobic environment, while the hydrophobicity tends to increase with rising DSC12. All six samples have high scattering intensity owing to the relatively large concentrated droplets ranging in the hydrodynamic radius from 50 to 110 nm, whereas the weight fraction of such large particles is substantially small except for the highest DSC12 sample. Most polymer chains for relatively low DSC12 of 0.076 were molecularly dispersed with a very small amount of large droplets. The dispersed chain has a slightly smaller helix pitch per residue and a more rigid main chain than those for amylose in dimethyl sulfoxide, suggesting that the amylosic main chain of C12CMA has a helical structure with dodecyl groups at least locally. On the other hand, an anisotropic shaped micelle-like structure is only found for relatively high DSC12 (0.23 and 0.39) samples, which was detected by the SAXS profile at a high scattering vector range. The micelle structure for high DSC12 samples is consistent with the high chain stiffness.

Adsorption and aggregation properties of alkoxy-group-modified homogeneous polyoxyethylene alkyl ether nonionic surfactants

The development of new surfactants with interesting properties and new functionalities that can be controlled in a simple manner is an important industrial objective. Herein, we report the synthesis of homogeneous polyoxyethylene (EO) alkyl ether nonionic surfactants modified with alkoxy groups (C12EO8OR, where C12 and EO8 are dodecyl and octaoxyethylene chains, respectively, and R = Me and Et) from a homogeneous EO-type hexaoxyethylene dodecyl ether (C12EO6) and diethylene glycol monomethyl ether or diethylene glycol monoethyl ether. The adsorption and aggregation properties of these surfactants were characterized through cloud point and surface tension measurements, and by small-angle X-ray scattering, polarization microscopy, and cryogenic transmission electron microscopy; these properties were compared to those of previously reported homogeneous EO-type (C12EO8) and polyoxypropylene-polyoxyethylene type surfactants (C12EO8POy, y = 1, 2, 3). The introduction of a methoxy or ethoxy group at the terminus of the EO chain in C12EO8 resulted in an increase in hydrophobicity and a greatly reduced cloud point. Substitution of the terminal hydroxy group of the EO chain in C12EO8 with methoxy and then ethoxy led to increasingly lower surface tensions in solution and more efficient air/water interfacial adsorption. C12EO8OR formed small micelles at low concentrations in solution, and the micelles of C12EO8OMe transformed to hexagonal liquid crystals with increasing surfactant concentration, whereas C12EO8OEt remained to form micelles even at high concentration; that is, the introduction of bulkier functional groups into the C12EO8 surfactant helps to control the formation of aggregates with higher-order structures.

Structure and Catalytic Activities of Gold Nanoparticles Protected by Homogeneous Polyoxyethylene Alkyl Ether Type Nonionic Surfactants.

Gold nanoparticles were prepared in aqueous solutions containing four homogeneous polyoxyethylene (EO) alkyl ether type nonionic surfactants: octaoxyethylene dodecyl ether (C12EO8), methoxyoctaoxyethylene dodecyl ether (C12EO8OMe), ethoxyoctaoxyethylene dodecyl ether (C12EO8OEt), and trioxypropylene-octaoxyethylene dodecyl ether (C12EO8PO3). The sizes of obtained gold nanoparticles were almost independent of the terminal group in the EO surfactants; and the average sizes of nanoparticles prepared by surfactants with hydroxy, methoxy, ethoxy, and trioxypropylene terminal groups at [surfactant]:[Au3+] = 1:1 were 5.1 ± 1.2, 8.1 ± 1.4, 6.4 ± 2.1, and 8.6 ± 2.9 nm, respectively. The gold nanoparticles easily aggregated together according to the increasing hydrophobicity of hydroxy < methoxy ethoxy < trioxypropylene terminal groups. Highly stable dispersed nanoparticles were observed with hydroxy group in the EO terminal group. On the other hand, introducing hydrophobic moiety to the hydroxy group resulted in aggregated nanoparticles because of the interaction between the hydrophobic groups of a protective agent for the gold nanoparticles. For the reduction reaction of p-nitrophenol and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging reaction, catalytic activities of the prepared gold nanoparticles decreased by the introduction of methoxy, ethoxy, or trioxypropylene to the hydroxy group of the EO type surfactant. Thus, a significant correlation was observed between the structure of gold nanoparticles and their catalytic activities.

Therapeutic effects and anti-metastasis effects of cationic liposomes against pancreatic cancer metastasis in vitro and in vivo

The anti-metastatic effects of cationic liposomes (CL) composed of 87 mol% dimyristoylphosphatidylcholine (DMPC), 8 mol% O,O′-ditetradecanoyl-N-(α–trimethylammonioacetyl) diethanolamine chloride (2C14ECl) and 5 mol% polyoxyethylene(21) dodecyl ether (C12(EO)21) was investigated for human pancreatic cancer (BxPC-3) cells. The inhibitory effect of CL on the migration of BxPC-3 cells was observed based on a wound scratch assay. CL suppressed pseudopodium formation of BxPC-3 cells. The anti-invasive effect of CL against BxPC-3 cells was observed via a Matrigel invasion assay. The anti-invasive effect of CL for BxPC-3 cells was found to occur through the inhibition of MMP2, MMP9, and MMP14. Overall, the results of this study revealed for the first time, the therapeutic effects and anti-metastasis activity of CL in xenograft mouse models for peritoneal metastasis of human pancreatic cancer.

One-Pot Method for Preparation of Magnetic Multi-Core Nanocarriers for Drug Delivery.

The development of various magnetically-responsive nanostructures is of great importance in biomedicine. The controlled assembly of many small superparamagnetic nanocrystals into large multi-core clusters is needed for effective magnetic drug delivery. Here, we present a novel one-pot method for the preparation of multi-core clusters for drug delivery (i.e., magnetic nanocarriers). The method is based on hot homogenization of a hydrophobic phase containing a nonpolar surfactant into an aqueous phase, using ultrasonication. The solvent-free hydrophobic phase that contained tetradecan-1-ol, γ-Fe2O3 nanocrystals, orlistat, and surfactant was dispersed into a warm aqueous surfactant solution, with the formation of small droplets. Then, a pre-cooled aqueous phase was added for rapid cooling and the formation of solid magnetic nanocarriers. Two different nonpolar surfactants, polyethylene glycol dodecyl ether (B4) and our own N1,N1-dimethyl-N2-(tricosan-12-yl)ethane-1,2-diamine (SP11), were investigated for the preparation of MC-B4 and MC-SP11 magnetic nanocarriers, respectively. The nanocarriers formed were of spherical shape, with mean hydrodynamic sizes <160 nm, good colloidal stability, and high drug loading (7.65 wt.%). The MC-B4 nanocarriers showed prolonged drug release, while no drug release was seen for the MC-SP11 nanocarriers over the same time frame. Thus, the selection of a nonpolar surfactant for preparation of magnetic nanocarriers is crucial to enable drug release from nanocarrier.

Inhibitory effect of hybrid liposomes on the growth of liver cancer stem cells

PurposeCancer stem cells (CSCs), also known as tumor-initiating cells, are involved in tumor progression, metastasis, and drug resistance. Hybrid liposomes (HLs) are nano-sized liposomal particles that can be easily prepared by ultrasonicating a mixture of vesicular and micellar molecules in buffer solutions. In this study, we investigated the inhibitory effects of HL on the growth of CSC subpopulations in liver cancer cells (HepG2) in vitro. MethodsHLs composed of 90 mol% L-α-dimyristoylphosphatidylcholine and 10 mol% polyoxyethylene(23) dodecyl ether were prepared by sonication. Cell viability was determined by the trypan blue exclusion assay. In liver cancer cells, CSCs were identified by the presence of the cell surface marker proteins CD133 and EpCAM by flow cytometry. A soft agar colony formation assay was performed using HepG2 cells pretreated with HLs. ResultsHLs selectively inhibited liver cancer cell growth without affecting normal hepatocytes. Additionally, HLs induced apoptosis of HepG2 cells by a"ctivating caspase-3. Notably, the CD133(+)/EpCAM(+) CSC sub-population of liver cancer cells treated with HLs was reduced. Furthermore, HLs markedly decreased the number of colony-forming cells. Finally, we confirmed the fusion and accumulation of HLs into the cell membranes of CSCs using a fluorescently labeled lipid (NBDPC). Significant accumulation of HL/NBDPC into the CSCs (particularly EpCAM(+) cells) occurred in a dose-dependent manner. ConclusionThese results suggest that HLs are a novel nanomedical therapeutic agent for targeting CSCs in liver cancer therapy.

Theranostics with Hybrid Liposomes in an Orthotopic Graft Model Mice of Breast Cancer.

This study aimed to elucidate the therapeutic effects of hybrid liposomes (HL) composed of L-α-dimyristylphosphatidylcholine (DMPC) and polyoxyethylene [25] dodecyl ether (C12(EO)25) and the ability of HL-containing fluorescent probe to detect cancer in orthotopic graft model mice of breast cancer (MDA-MB-453). HL composed of 90 mol% DMPC and 10 mol% C12(EO)25 were prepared by the sonication method. Anti-tumor activities of HL were investigated in vivo using orthotopic graft-bearing mice of MDA-MB-453 cells. With regard to the therapeutic effects of HL for breast cancer, HL inhibited the growth of MDA-MB-453 cells and induced apoptosis. Intravenous administration of HL resulted in a remarkable reduction of relative tumor weight in orthotopic graft model mice of breast cancer. The TUNEL assay revealed that this effect was due to induction of apoptosis. With regard to detection (diagnosis) of breast cancer, enhanced accumulation of HL carrying a fluorescence probe (Indocyanine green; ICG) was observed for MDA-MB-453 cells, although no accumulation of HL/ICG was obtained for normal breast cells. Enhanced accumulation of HL/ICG into the tumor of orthotopic graft model mice of breast cancer was observed. HL and HL/ICG could be theranostic targets since they showed therapeutic effects and ability to detect (diagnose) cancer in an orthotopic graft model mouse of breast cancer (MDA-MB-453).

Characterization of a Heptaoxyethylene Dodecyl Ether Standard Solution by a Combination of &lt;sup&gt;1&lt;/sup&gt;H Quantitative NMR Spectroscopy and HPLC

Characterization of a Heptaoxyethylene Dodecyl Ether Standard Solution by a Combination of &lt;sup&gt;1&lt;/sup&gt;H Quantitative NMR Spectroscopy and HPLC

Temperature Resistant Binary SLES/Nonionic Surfactant Mixtures at the Air/Water Interface.

Surface compositions of adsorbed monolayers at the air/water interface, formed from binary surfactant mixtures in equilibrium, have been studied using neutron reflectivity at three discrete temperatures: 10, 25, and 40 °C. The binary compositions studied are sodium lauryl dodecyl ether sulfate (SLES EO3)/C12E n, where n = 6 and 8, at a fixed concentration of 2 mM with and without the addition of 0.1 M NaCl. Without NaCl, the nonionic surfactant dominates at the interface and nonideal mixing behavior is observed. This is modeled using the pseudophase approximation with a quadratic expansion of the free energy of mixing. The addition of 0.1 M NaCl screens the charge interaction between the surfactants and drives the surface composition of each system closer to that of the bulk composition. However, model fits to both the micelles and surface layers suggest that nonideal mixing is still taking place, although it is difficult to establish the extent of nonideality due to the limited data quality. The effect of temperature changes on the surface adsorption and composition of the surfactant mixtures is minimal and within error, with and without NaCl, but the critical micelle concentrations are significantly affected. This indicates the dominant influence of steric hindrances and surfactant charge interactions in determining interfacial behavior for these surfactants, relative to the temperature changes. The study also highlights the delicate effect of a relatively small change in the number of EO groups on mixing behavior.

Understanding of the foam capability of sugar-based nonionic surfactant from molecular level

In this paper, the correlation of the interfacial molecular array behavior of sugar-based green surfactant dodecyl maltoside DDM, and its apparent foam properties was investigated by molecular dynamics simulation and quantum chemical calculation as well as experimental methods. A common nonionic surfactant nona-ethylene glycol dodecyl ether C12E9, which has same hydrophobic tail and similar O atom number in headgroup with DDM, was studied as a reference. It was found that, not only the array behaviors of hydrophilic groups of DDM and C12E9 at the air-water interface, but also the intermolecular interactions were quite different. The simulation finding agreed well with the experimental results, by which how the interfacial molecular array behavior of the two types of nonionic surfactants affect the foam properties was revealed, and the application potential of DDM being used as foam stabilizer under diverse harsh conditions, such as high salinity, high temperature, strong acid and alkali, was presented, which should be quite meaningful.

An insight into effect of micelle-forming surfactants on aqueous solubilization and octanol/water partition coefficient of the drugs gemfibrozil and ibuprofen

Aqueous micellar solubilization of ibuprofen and gemfibrozil drugs was investigated at constant temperature (25.0±0.1) °C and atmospheric pressure using shake-flask and UV–vis spectrophotometric techniques. The solubility measurement was done in presence of three surfactants possessing different head groups, namely sodium dodecylsulfate (anionic SDS), cethyltrimethylammonium bromide (cationic CTAB) and polyethylene glycol dodecyl ether (non-ionic Brij 35) as well as their binary mixtures. The micellar solubility descriptors of χ (molar solubilization capacity), K (micelle–water partition coefficient), and ΔGs∘ (standard free energy of solubilization) were obtained to estimate quantitatively the solubilization efficiency of the surfactant systems. Moreover, the octanol-water partition coefficient of these drugs was also evaluated in the micellar solutions. The results obtained in the aqueous micellar system demonstrate that, irrespective of the surfactant type, the solubility of drugs increases with increasing the concentration of micelles. It was found that the solubility of ibuprofen and gemfibrozil in Brij 35 and CTAB solutions, respectively is higher compared to that in the other surfactants. However, the partition coefficients of these drugs show an inverse trend with solubility data. Finally, the effect of the surfactant type on solubility enhancement of the drugs is explained in terms of possible interactions between the drug and the micelle.

Cesium-substituted mesoporous phosphotungstic acid embedded chitosan hybrid polymer membrane for direct methanol fuel cells

Non-ionic polyethylene glycol dodecyl ether (Brij 76) template novel single-step process is successfully evolved for preparation of mesoporous cesium salt of phosphotungstic acid (PTA) with tunable porosity. Hybrid proton exchange membranes are prepared by embedding mesoporous cesium salt of PTA into chitosan (CS) polymer and are characterized by FTIR, TGA, and SEM mapping studies. To elucidate advantages of mesoporous structure, a series of CS hybrid membranes comprising non-porous cesium salt of phosphotungstic acid is also prepared and their functional properties are compared with mesoporous counterparts. Mesoporous nature helps to integrate membrane network creating maximum intermolecular interaction between organic and inorganic components. Both selective water sorption feature of CS and highly hydrophilic nature of mesoporous cesium salt of PTA together play a vital role in selective proton transport process through CS/m-PTA hybrid membranes. At optimal loading of m-PTA, maximum peak power density of 83 mW cm−2 was achievable with 2 M methanol as a fuel feed. On the basis of thermal stability, low methanol crossover, and appropriate proton conductivity, CS/m-PTA-5 wt% hybrid membrane could be proposed as novel polyelectrolytes for direct methanol fuel cell.

Boosting Effect of Amphiphilic Random Copolymers for Bicontinuous Phases.

Amphiphilic random copolymers, poly(oxyethylene)/poly(oxypropylene) butyl ethers (C4EmPn), have been used as raw materials for cosmetics. This paper reports on the influence of amphiphilic random copolymers on mixtures of n-decane, water, and a nonionic surfactant, hexa(oxyethylene) dodecyl ether (C12E6). Bicontinuous phases are formed from decane/water/C12E6 mixtures at high C12E6 weight fractions (> 70 wt%). Adding C4EmPn to decane/water/C12E6 mixtures brings about the formation of bicontinuous phases and a decrease in the amount of the surfactant required for their formation, indicating efficiency boosting. The bicontinuous phase formation region in the phase diagram of the decane/water/C12E6+C4E5P5 system is largest at a specific C4E5P5 weight fraction in the C12E6/C4E5P5 mixture. When a hydrophobic polymer, in which the poly(ethylene oxide) group in C4EmPn is absent, is added to decane/water/C12E6 mixtures, no efficiency boosting is observed. These results suggest that the adjustment of the hydrophilicity-hydrophobicity balance of C12E6/C4EmPn mixture causes the efficiency boosting.