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In water, the nonionic surfactant pentaethylene glycol monododecyl ether (C12E5) forms multi-lamellar vesicles upon application of shear, attributed to buckling instability of the surfactant layers. In the standard setup for applying shear, a pair of solid substrates is moved in opposite directions, and a non-slip condition at the solid surface is assumed. Based on theoretical predictions, the effective viscosity of the fluid surrounding the membrane is modified in this process, and this confinement may affect membrane fluctuation. However, only a few studies have analyzed the structural changes near the substrate. From this viewpoint, the structural changes in surfactant aggregates near a solid substrate under the application of shear were investigated herein using neutron reflectometry (NR). By increasing the shear rate, shear thickening at a lower shear rate and shear thinning at a higher shear rate were observed, similar to that in the bulk. However, a discontinuous change in the lamellar structure accompanying the condensation of the surfactant was observed in the NR experiments. This study presents the first experimental evidence indicating that the ramping speed of shear rates governs the shear-induced structuring of surfactant aggregates near the surface. [ABSTRACT FROM AUTHOR]

Thermophoresis has emerged as a powerful tool for characterizing and manipulating colloids at the nano- and micro-scales due to its sensitivity to colloid–solvent interactions. The use of surfactants enables the tailoring of surface chemistry on colloidal particles and the tuning of interfacial interactions. However, the microscopic mechanisms underlying thermophoresis in surfactant solutions remain poorly understood due to the complexity of multiscale interaction coupling. To achieve a more fundamental understanding of the roles of surfactants, we investigated the thermophoretic behavior of silica beads in both ionic and nonionic surfactant solutions at various background temperatures. We provide a complete mechanistic picture of the effects of surfactants on interfacial interactions through mode-coupling analysis of both electrophoretic and thermophoretic experiments. Our results demonstrate that silica thermophoresis is predominantly governed by the dissociation of silanol functional groups at silica–water interfaces in nonionic surfactant solutions, while in ionic surfactant solutions, the primary mechanism driving silica thermophoresis is the adsorption of ionic surfactants onto the silica surface. [ABSTRACT FROM AUTHOR]

Innovative applications of foam are the need of time which fundamentally depends on the stability of the foam. In the present research work, the static foam behavior of the nonionic surfactant Tween-20 in the presence and absence of Titanium dioxide nanoparticles (TiO2-NPs) was investigated. The role of TiO2-NPs on foaming power based on foam height and foamability was studied at different temperatures. At 29 ± 1 0C, maximum foam height for Tween 20 (5% surfactant solution in distilled water) without and with TiO2-NPs was increased from 45.60 to 60.30 cm exhibiting 32.25% increase. In view of studying foam stability, axial dye displacement rate (ADDR) test was performed without and with nanoparticles where TiO2-NPs resist liquid drainage. TiO2 -NPs and Tween-20 form intermolecular hydrogen bonding which helps to enhance the foam stability as revealed by the density functional theory (DFT) studies. However, TiO2 -NPs have tendency to agglomerate if zeta potential value is low that severely affect the foaming power and foamability. [ABSTRACT FROM AUTHOR]

The encapsulation characteristics of chrysin (important flavonoid with potential food, pharmaceutical, and biomedical applications) was studied with nonionic surfactants Triton X-114 (TX) and Quillaja Saponin (QS), individually. The factors influencing the encapsulation efficiency (EE) of standard chrysin that is surfactant concentration, pH, NaCl concentration, and chrysin concentration were analyzed. The maximum EE of standard chrysin was found to be 98.23 ± 1.63% with TX micelles and 83 ± 2.31% with QS micelles under the following conditions: 0.02 mg/mL standard chrysin, 5% NaCl, pH 7, and 4% w/w TX 6% w/w QS. Selective extraction of chrysin from propolis was tried using three extraction techniques namely Maceration, Microwave-assisted Extraction (MAE), and Maceration with Microwave-assisted Extraction (MMAE). MAE, which gave a chrysin yield of 3 mg/g, was deemed the most suitable method for chrysin extraction from propolis. This MAE crude extract was subjected to encapsulation under the conditions previously optimized for standard chrysin. Specific encapsulation of chrysin from the propolis crude extract was achieved, with an EE of 92 ± 0.86% with TX and 84.97 ± 1.34% with QS. The encapsulated chrysin was characterized using particle size analysis and antioxidant activity. TX system was found to be the most suitable for the encapsulation, as it was able to selectively encapsulate chrysin from propolis, despite the presence of other interfering flavonoids in the crude extract. The microwave-assisted extraction combined with surfactant-based micellar encapsulation can be said to be an effective process for the extraction and encapsulation of chrysin from propolis. [ABSTRACT FROM AUTHOR]

[Display omitted] Aqueous solutions of long-chain water-soluble sucrose ester surfactants exhibit non-trivial response to temperature variations, revealing a peak in viscosity around 40–50 °C. While previous investigations have explored the structures within sucrose stearate systems at various constant temperatures, a comprehensive understanding of the entire temperature dependence and the underlying molecular factors, contributing to this phenomenon is currently missing. Temperature dependent properties and supramolecular structures formed in aqueous solutions of commercial sucrose palmitate were examined using SAXS/WAXS, DSC, optical microscopy, rheological measurements, NMR, and cryo-TEM. The underlying mechanism governing this unusual behavior is revealed and is shown to relate to the mono- to di-esters ratio in the solutions. Solutions primarily containing sucrose monoesters (monoesters molecules ≳ 98% of all surfactant molecules) exhibit behavior typical of nonionic surfactants, with minimal changes with temperature. In contrast, the coexistence of mono- and di-esters results in the formation of discrete monodisperse diester particles and a network of partially fused diester particles at low temperature. As the temperature approaches the diesters' melting point, wormlike mixed micelles form, causing a viscosity peak. The height of this peak increases significantly with the diester concentration. Further temperature increase leads to fluidization of surfactant tails and formation of branched micelles, while excess diester molecules phase separate into distinct droplets. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the in vitro performance of self-nanoemulsifying drug delivery systems (SNEDDSs) of Ornidazole (ORD), a poorly water-soluble drug. Self-nanoemulsifying drug delivery systems of ORD were prepared using various oils, non-ionic surfactants, and/or water-soluble co-solvents and assessed visually/by droplet size measurement. Equilibrium solubility of ORD in the anhydrous and diluted SNEDDS was conducted to achieve the maximum drug loading. The in vitro dissolution of SNEDDS was studied to compare the solubility of the representative formulations with API. The results from the characterization and solubility studies showed that SNEDDS formulations were stable with lower droplet sizes and showed higher ORD solubility. From the dissolution studies, it was found that the developed A7-SNEDDS formulation provided a significantly higher rate of ORD release (98.94 ± 0.68 in 1.0 h) compared to API. ORD-loaded SNEDDS formulations could be a potential oral pharmaceutical product with high drug-loading capacity, improved drug dissolution, and enhanced oral bioavailability. [ABSTRACT FROM AUTHOR]

AbstractThe nonionic surfactant was considered to be the most effective surfactant for the treatment of oily sludge. In this paper, Tween20 and Span80 (T/S) composite surfactant was chosen as emulsifier for the preparation of microemulsion, and their synergistic effect was explored. Clint equation and molecular dynamics simulation was used to interpret the formation of mixed micelles and the results showed that T/S composite surfactant with the mass ratio of 11:1 exhibited the good synergetic effect. Then, the microemulsion prepared using composite surfactants was applied for the treatment of oily sludge. Under the optimal conditions of solid-liquid ratio of 1:1(g: mL), stirring temperature of 40 °C, stirring time of 30 min and stirring speed of 400 rpm, the residual oil rate was reduced to 0.25%, which was much lower than other reported results using chemical methods. Interface tensiometer and quartz crystal microbalance measurement showed that the interfacial tension decreased significantly after the addition of composite surfactant. This work provides a feasible strategy for oily sludge treatment using microemulsion, which promoted the development of oily sludge treatment processes based on microemulsion in practical industry. [ABSTRACT FROM AUTHOR]

Lycopene is a natural carotenoid with well-known benefits due to its antioxidant properties, including an anti-inflammatory effect in colorectal cancer and anti-angiogenic effects along with a reduction in the risk of prostate cancer and coronary heart disease. Due to their poor water solubility, photosensitivity and heat sensitivity, their incorporation in cosmetic and food matrices should be through encapsulation systems. In the present work, lycopene-loaded emulsions were prepared using two different types of stabilizers: non-ionic surfactants, testing several ratios of Tween 80 and Span 80, and chitosan, using chitosans of different viscosities and molecular weights. Soybean oil was found to be a suitable candidate for O/W emulsion preparation. Lycopene encapsulation efficiency (EE) of 70–75% and loading capacities of 0.14 mg/g were registered in stable emulsions stabilized either by non-ionic surfactants or acidified chitosans. Therefore, chitosan is a good alternative as a sustainable stabilizer to partially replace traditional synthetic ingredients with a new biodegradable, renewable and biocompatible material which could contribute to reduce the environmental impact as well as the ingestion of synthetic toxic materials by humans, decreasing their risk of suffering from chronic and complex pathologies, among which several types of cancer stand out. [ABSTRACT FROM AUTHOR]

Deionized water is replacing fluorinated liquids as the preferred choice for two-phase immersion cooling in data centers. Yet, insufficient bubble removal capability at low saturated pressure is a key challenge hindering the widespread application. To solve this issue, this study employs non-ionic surfactant (Tween 20) and asymmetric structures (expanding microchannel) to enhance the boiling performances of deionized water under sub-atmospheric pressure. The research examines the effects of pressure (8.8~38.5 kPa), surfactant concentration (0.1~0.5 mL/L), and heat flux density (10~180 W/cm2) on the boiling heat transfer characteristics and analyzes the mechanism of unusual temperature oscillations induced by surfactants. It was found that the trade-off between the sub-atmospheric pressure, surface tension coefficient, and reduced static contact angle results in pronounced intermittent boiling on the heated surface. Even with the addition of surfactants, the improvement in heat transfer requires demanding conditions. Boiling enhancement throughout all heat flux conditions was achieved when the surfactant concentration was higher than 0.2 mL/L for the expanding microchanneled surface. The heat transfer coefficient reached 6.89 W·cm−2·K−1 under 8.8 kPa, which was 45% higher than without the surfactant. Under the same heat flux and sub-atmospheric pressure, as the concentration increased from 0.1 to 0.5 mL/L, the amplitudes of temperature fluctuation of the plane surface and expanding microchanneled surface decreased from 10 K to 2 K and 18 K to 1 K, respectively. The onset of nucleate boiling and wall superheat of the expanding microchanneled surface gradually decreased with the increase in surfactant concentration, where the onset of nucleate boiling decreased by 10.54 K. When the heat flux is 160 W/cm2, the wall superheat is reduced by 12.8 K. [ABSTRACT FROM AUTHOR]

The release of hydrocarbons (HC) into the marine environment has serious consequences, both economically and ecologically. This work presents an efficient process to remove HC pollution from seawater: cloud point extraction (CPE), considered to be a reliable, inexpensive, and environmentally friendly method, using the readily biodegradable nonionic surfactants Lutensol ON30 and Tergitol 15‐S‐7. A real salt water sample with a high chemical oxygen demand (COD = 1700 mg O2/L) was thus treated. First, the phase diagrams of the binary systems (water–surfactant), and the pseudo‐binary systems (water–surfactant–HC), were determined. Second, after a 24 h settling time, considered as optimal, the extraction results, that is, residual soluble COD, residual percentage of surfactant in the dilute phase and volume fraction of coacervate at equilibrium, were expressed in terms of temperature and initial surfactant concentration. For each parameter, the results obtained were modeled using the response surface methodology and represented on three‐dimensional diagrams. They show that the COD can be reduced to 10 and 15 mg O2/L, using Lutensol ON30 and Tergitol 15‐S‐7, respectively, under seawater temperature conditions. Finally, it was shown that the surfactant can be recycled. The present work demonstrates that CPE can reduce the HC content of seawater on a laboratory scale. [ABSTRACT FROM AUTHOR]

This study delves into the optimization of niosomal production for biological applications, focusing on their emerging role as amphiphilic nanoparticles derived from nonionic surfactants, poised at the forefront of biomedical research. We aimed to formulate and characterize a diverse array of niosomal nanoparticles, with particular emphasis on process‐related parameters and physicochemical characteristics. Critical thresholds for size, polydispersity, and zeta potential were established to identify parameters crucial for optimal niosomal formulations through a comprehensive investigation of concentrations, sonication times, ingredient ratios, and surfactant types. Leveraging MODDE software, we generated 10 optimized formulations from preliminary parameter screening. The proposed experimental model design by the software exhibited acceptable similarity to the obtained experimental results (F‐score: 0.83). The criteria for selection of the predicted experimental model formed based on targeted physicochemical considerations. To enhance half‐life and penetration, especially in higher electrostatic regions like the central nervous system (CNS), we proposed a neutralized surface charge (−10 to 10 mV) while maintaining size within 100–200 nm and polydispersity below 0.5. Extended stability screening revealed periodic and extended Gaussian distributions for size and zeta potential to minimize flocculation and coagulation caused by neutralized surface charge. Notably, the cellular response performance of optimized niosomes was assessed via cellular binding, uptake, and viability in comparison with liposomes. Glioblastoma cell line (U‐87) and granulocyte colony‐stimulating factor (G‐CSF) containing lymphoblastic leukemia cell line (NFS‐60) were chosen to represent tumors developed in the CNS region and white blood cells, respectively, enabling a comprehensive comparative analysis with liposomes. The meticulous comparison between niosomes and liposomes revealed comparable cellular viability profiles on both U‐87 and NFS‐60 cell lines, highlighting their similarities in cellular interactions. Moreover, selected niosomal formulations demonstrated exceptional cellular uptake, either equaling or surpassing observed liposomal uptake. One of the most promising niosomes was selected and optimized to evaluate drug encapsulation performance of niosomes for further drug delivery adaptations by one of the chemotherapy drugs, paclitaxel (PTX). Cytotoxicity study was established with the most efficiently encapsulated niosomal condition with human‐derived fibroblasts (HDFs) and U‐87 as the representation of healthy and cancerous cell lines. Results demonstrated 1:100 diluted PTX‐loaded niosome in the certain concentration demonstrated favorable toxicity in U‐87 than original PTX at the same concentration while not disturbing healthy HDFs. These findings underscore the potential of niosomes for reliable drug delivery, challenging the dominance of liposomal vehicles and presenting economically viable nanocarriers with significant implications for advancing biomedical research. [ABSTRACT FROM AUTHOR]

Nano-emulsions stabilized by nonionic surfactants have the characteristics of ultra-low interfacial tension (IFT) and altered wettability in ultra-low permeability reservoirs. Thus, in this work, a new nanoemulsion is proposed to enhance spontaneous imbibition recovery in ultra-low permeability reservoirs. The nanoemulsion is prepared using n-dodecane, Tween-20, and coconut oil acid diethanolamine n-amyl alcohol. The effects of temperature and salinity on particle size, IFT, and wettability alteration performance of the nanoemulsions were systematically studied. Experimental results show that the particle size of nanoemulsions increases with salinity, and the highest level is up to 100 nm, while an increase in temperature is beneficial to the formation of smaller nanoemulsions. The IFT of the nanoemulsion system can be reduced to an ultra-low level (10–3 mN/m) when the salinity is lower than 50,000 mg/L. As for the wettability alteration property of a nanoemulsion system, an increase in temperature can improve its performance, but variations in salinity seldom have any effects. At 56 °C and 30,000 mg/L salinity, the spontaneous imbibition recovery of 1.00 wt% nanoemulsion can reach 53.8% under the synergistic effect of three mechanisms: extremely small droplet size, excellent wettability alteration performance, and ultra-low IFT. These three mechanisms work together to significantly improve the displacement efficiency of ultra-low-permeability reservoirs. [ABSTRACT FROM AUTHOR]

Cloud point (CP) of aqueous solution of metformin hydrochloride (MNH) and triton X-100 (TX-100) was examined in presence of several alcohols (MeOH, EtOH, 1-PrOH, 2-PrOH, and 1-BuOH). The main focal point of this study was to evaluate the cloud development for the combination of TX-100 and MNH, as well as to indicate the mode of how various alcohols influence both the physicochemical parameters and interaction forces of that mixture. The cloud point (CP) measurement technique was chosen because of its broad applicability in both the medical and industrial sectors. As alcohol contents increased, higher CP values of TX-100 and MNH mixture were observed except in aq. 1-BuOH (CP is decreased). In the aqueous alcoholic medium (above 3000 mmol·kg−1), the phase separation of TX-100 (92.7 mmol·kg−1) and MNH (2 mmol·kg−1) mixture showed the subsequent trend: CP (H2O + 2-PrOH) ˃ CP (H2O + MeOH) > CP (H2O + EtOH) ˃ CP (H2O + 1-PrOH). It was observed that the depth to which alcohol molecules penetrate micelles is influenced by the length of the alcohol chain. Longer hydrophobic alcohol molecules have the ability to impair more ethylene oxide–water (EO-water) interactions by penetrating deeper into the micelle's palisade layer. As a result, there is more occurrence of dehydration, which promotes the production of micellar particles as well as lowers the cloud point substantially. The calculated Δ G c 0 values of the TX-100 + MNH mixture in alcohols media are appeared as positive in every scenario examined, proving that the clouding procedure is not spontaneous. The positive Δ G c 0 results might be attributed to the surfactant's surface layer in forming H-bond via the water molecules. A decrease in the positive Δ G c 0 values is evidenced by a rise in alcohol concentrations. Consequently, there is less non-spontaneity at higher alcohol concentrations. The + Δ H c 0 (endothermic) and + Δ S c 0 magnitudes are detected in aq. MeOH, EtOH, and 2-PrOH solutions. However, Δ H c 0 and Δ S c 0 magnitudes are found as positive (endothermic) and negative (exothermic) at lower and higher contents of 1-PrOH solution while the opposite trend in the Δ H c 0 and Δ S c 0 was detected in aq. 1-BuOH solution. Possible interactions among TX-100 and metformin hydrochloride in aqueous 1-BuOH media [ABSTRACT FROM AUTHOR]

Combinatorial chemistry and drug design have produced more lipophilic, heavier, and less water soluble drugs in recent years. It is more difficult to find the best drug delivery system for them. In this area of technology and drug development, new strategies are applied to develop novel drug moieties and improve their water solubility. One of the main obstacles is the use of poorly water soluble chemicals in formulation. Beta-ionone (β-ionone) is utilised to target many forms of cancer and has been shown to have anticancer potential in recent studies, however it has poor water solubility. The goal of the current study was to enhance the solubility of beta-ionone using various carrier materials like non-ionic water-dispersible surfactant Gelucire® 50/13 (polyoxylglycerides) which self-emulsifies in aqueous media forming a fine micro-dispersion. Another amphiphilic material, Soluplus® (polyvinyl caprolactam-polyvinyl acetate-polyethylene glycol graft copolymer was used to enhance the solubility of beta-ionone. Further, Hydroxypropyl-β-Cyclodextrin inclusion complex was also prepared and evaluated to check the improvement in the solubility of beta-ionone. Finally, the performance of these carries was checked by developing the pellet formulation. An appropriate formulation offers a method to improve the solubility, dissolution, and bioavailability of β-ionone. When compared to alternative cancer treatment options, this formulation may aid to improve patient compliance and the drug's effectiveness. The pellet formulation developed utilising HP-β-CD has produced outstanding results and may be more stable due to the inclusion-capabilities, complexes. [ABSTRACT FROM AUTHOR]

Nanoemulsions are kinetically stable emulsions with droplet size distribution in the range of 10–500 nm. Low interfacial tension (IFT), small droplet size, and wettability alteration properties of nanoemulsions have led to their application for enhanced oil recovery (EOR) EOR. The current study deals with the formulation and characterization of Tergitol 15-S-9 surfactant stabilized oil/water nanoemulsion (NE). Optimal surfactant concentration accompanied by optimal salinity determination was done by observing long-term stability. The stability of the nanoemulsions was analyzed by Turbiscan and Zeta potential analysis. The optimal nanoemulsion was characterized in terms of droplet size, rheology, wettability, miscibility, and IFT. All the prepared nanoemulsion showed particle size < 300 nm. optimized nano emulsion, that is, 0.5 wt.% surfactant +0.5 wt.% salinity showed good IFT reduction and wettability alteration capability. Nanoemulsion also showed good miscibility behavior with actual crude oil at 60 °C. Rheology of the formed emulsion shows a mixed nature that is shear thinning as well as shear thickening nature which is favorable for heterogeneous reservoirs. Core-flooding experiments were conducted at optimized nanoemulsion formulation, and additional oil recovery of 13.93% of the original oil in place was obtained after the conventional water flooding. Highlights: Experimental and mechanistic investigation of nanoemulsions for oil recovery. Enhanced miscibility of Tergitol 15-S-9 stabilized nanoemulsion with crude oil. Viscosity enhancement by macromolecular and supramolecular network structures. Low IFT achieved for the nanoemulsion resulting enhanced oil displacement. Encouraging oil displacement by injection of formulated nanoemulsion. [ABSTRACT FROM AUTHOR]

In this study, a new method was introduced to induce micellar transitions by using vesicles formed from mixed surfactants, which offer enhanced stability. Different physicochemical analysis methods were used to study the transition mechanism and the aggregation behavior of the mixed aqueous system composed of the double‐chain cationic didodecyldimethylammonium bromide (DDAB) and a single‐chain nonionic fluorinated surfactant undecafluoro n‐pentyl decaoxyethylene ether (C5F11(EO)10), by varying the fraction of DDAB, then the total surfactant concentration of DDAB/C5F11(EO)10 mixed system at XDDAB = 0.9. The obtained results indicated that the addition of the fluorinated surfactant C5F11(EO)10 to the mixed system resulted in a reduction of the surface tension (γ) and a decrease in the Electrical conductivity (K). Furthermore, even at high total concentrations of the mixed system, the conductivity and charge density at the surface remained stable. As XDDAB values increased, a higher degree of dissociation (α) was observed, along with negative values in the thermodynamic parameters of micellization (ΔGCMC°$$ {G}_{\mathrm{CMC}}^{{}^{\circ}} $$, ΔGCVC°$$ {G}_{\mathrm{CVC}}^{{}^{\circ}} $$, and ΔGads°$$ {G}_{\mathrm{ads}}^{{}^{\circ}} $$), confirming the transition from micelles to vesicles. The dynamic light scattering (DLS) analysis revealed the formation of two stable types of aggregates at both low and high concentrations, as supported by the zeta potential (ζ). Upon increasing the concentration of surfactants, UV–Vis absorption measurements indicated that small spherical micelles grow into large multilamellar vesicles, as evidenced by an increase in turbidity and confirmed transmission electron microscopy images. [ABSTRACT FROM AUTHOR]

BACKGROUND RESULTS CONCLUSION Flavonoids, found in common vegetables and fruits, have health benefits that are often limited by their low bioavailability. Excipient emulsions provide an effective strategy to overcome these obstacles. However, the nature of the emulsifier used to formulate excipient emulsions and the chemical structure of the flavonoids both affect the bioaccessibility of the flavonoids.The purpose of this study was to investigate the impact of the interfacial properties of excipient emulsions on the in vitro gastrointestinal fate of representative structural flavonoids (quercetin, kaempferol, and apigenin) through the INFOGEST method. Tween 80 (TW80) (a nonionic surfactant) was more effective at reducing the oil–water interfacial tension than whey protein isolate (WPI) (a protein‐based emulsifier) or octenyl succinic anhydride (OSA)‐modified starch (MS) (a polysaccharide‐based emulsifier). Moreover, TW80 created excipient emulsions with smaller oil droplets, which were more resistant to oral and gastric conditions. The WPI‐emulsions underwent severe flocculation in the gastric phase, leading to an appreciable increase in particle size (from 220 to 3000 nm). The TW80‐coated oil droplets were more digestible than WPI‐ or MS‐coated ones. This was attributed to the larger lipid surface area for lipase attachment. The bioaccessibility of quercetin, kaempferol, and apigenin was also affected by emulsifiers: TW 80 (25% to 45%) > WPI (14% to 29%) ≈ MS (15% to 25%). Flavonoid bioaccessibility appeared to be related to their molecular properties.This study provides guidance for the design of effective excipient emulsions to enhance the bioavailability of flavonoids. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

The present study explores the cleaning efficacy of a set of nonionic surfactants (linear ethoxylated alcohol, secondary ethoxylated alcohols with 5, 7, and 9 ethoxy groups, glycoside surfactants, polyglycerol surfactants, and an ethoxylated sorbitan monolaurate) combined with cationic biocides—alkyl quaternary ammonium salts. A simple hard surface cleaning methodology was applied, which was shown to discriminate well between poor and good cleaning formulations. In addition to cleaning efficacy, surface aesthetics such as gloss and haze were evaluated together to assess surface streaking caused by a residual surfactant layer. The haziness determination turned out to be the key feature revealing the complex cleaning performance of multi‐component products. [ABSTRACT FROM AUTHOR]

The present work aimed to evaluate whether the use of an innovative method such as hydrodynamic cavitation (HC) is suitable for the simultaneous removal of surfactants of different chemical natures (non-ionic, anionic and cationic) from actual car wash wastewater at different numbers of passes through the cavitation zone and different inlet pressures. An additional novelty was the use of multi-criteria decision support, which enabled the selection of optimal HC conditions that maximized the removal of each group of surfactants and chemical oxygen demand (COD) with minimal energy input. For the optimal HC variants, Fourier transform infrared spectroscopy (FT-IR/ATR) as well as investigations of surface tension, zeta potential, specific conductivity, system viscosity and particle size were carried out. The highest reduction of non-ionic surfactants was found at 5 bar inlet pressure and reached 35.5% after 120 min. The most favourable inlet pressure for the removal of anionic surfactants was 3 bar and the removal efficiency was 77.2% after 120 min, whereas the most favourable inlet pressure for cationic surfactant removal was 3 bar, with the highest removal of 20% after 120 min. The obtained results clearly demonstrate that HC may constitute an effective, fast and cost-efficient method for removing surfactants from real industrial wastewater. [ABSTRACT FROM AUTHOR]

[Display omitted] • Cryo-electron tomography was used to determine the structural characteristics of complicated surfactant aggregates. • Transitions branched WLMs → saturated network of WLMs → perforated vesicles were observed in solutions of zwitterionic and nonionic surfactants. • Transformations proceed through an increase in the number of branches at the expense of cylindrical subchains and semispherical endcaps. • Exponential distribution of subchains length was confirmed experimentally for multiconnected saturated networks. • Perforated vesicles were observed when the length of subchains became much shorter than the persistence length. The formation of micellar aggregates and the changes in their morphology are crucial for numerous practical applications of surfactants. However, a proper structural characterization of complicated micellar nanostructures remains a challenge. This paper demonstrates the advances of cryo-electron tomography (cryo-ET) in revealing the structural characteristics that accompany the evolution of surfactant aggregates. By using cryo-ET in combination with cryo-transmission electron microscopy (cryo-TEM), small-angle neutron scattering (SANS), and rheometry, studies were carried out on a model system composed of zwitterionic and nonionic surfactants. In this system, the molecular packing parameter was increased gradually by increasing the molar fraction of nonionic surfactant. A series of structural transformations was observed: linear wormlike micelles (WLMs) → branched WLMs → saturated network of multiconnected WLMs → perforated vesicles (stomatosomes). The transformations occur through an increase in the number of branches at the expense of cylindrical subchains and semispherical endcaps. Exponential distribution of subchains length was confirmed experimentally for multiconnected saturated networks. The stomatosomes were formed when the length of subchains becomes much shorter than the persistence length, causing the three-dimensional (3D) structure to transform into a two-dimensional (2D) membrane. This work identifies the mechanism of the structural changes, which can be further used to design various surfactant self-assemblies. [ABSTRACT FROM AUTHOR]

[Display omitted] Nonionic surfactants can counter the deleterious effect that anionic surfactants have on proteins, where the folded states are retrieved from a previously unfolded state. However, further studies are required to refine our understanding of the underlying mechanism of the refolding process. While interactions between nonionic surfactants and tightly folded proteins are not anticipated, we hypothesized that intermediate stages of surfactant-induced unfolding could define new interaction mechanisms by which nonionic surfactants can further alter protein conformation. In this work, the behavior of three model proteins (human growth hormone, bovine serum albumin, and β-lactoglobulin) was investigated in the presence of the anionic surfactant sodium dodecylsulfate, the nonionic surfactant β-dodecylmaltoside, and mixtures of both surfactants. The transitions occurring to the proteins were determined using intrinsic fluorescence spectroscopy and far-UV circular dichroism. Based on these results, we developed a detailed interaction model for human growth hormone. Using nuclear magnetic resonance and contrast-variation small-angle neutron scattering, we studied the amino acid environment and the conformational state of the protein. The results demonstrate the key role of surfactant cooperation in defining the conformational state of the proteins, which can shift away or toward the folded state depending on the nonionic-to-ionic surfactant ratio. Dodecylmaltoside, initially a non-interacting surfactant, can unexpectedly associate with sodium dodecylsulfate-unfolded proteins to further impact their conformation at low nonionic-to-ionic surfactant ratio. When this ratio increases, the protein begins to retrieve the folded state. However, the native conformation cannot be fully recovered due to remnant surfactant molecules still adsorbed to the protein. This study demonstrates that the conformational landscape of the protein depends on a delicate interplay between the surfactants, ultimately controlled by the ratio between them, resulting in unpredictable changes in the protein conformation. [ABSTRACT FROM AUTHOR]

This research investigates the impact of gamma irradiation on epoxy-MWCNT nanocomposites for satellite deployment mechanisms. Nanocomposites, enhanced with surfactants, were meticulously prepared and subjected to controlled gamma irradiation (250–1000 kGy) utilizing the Cobalt-60 facility Industrial Mega Gamma-1 at NCRRT in Egypt. Surface tension measurements explored surfactant effects on epoxy-MWCNT composites in acetone. Acetone reduced tension from 26.7 to be 24.2 (mN/m). Surfactants (Tween 80, SDS) effectively lowered tension (24.4 mN/m), while surfactant-free systems had higher tension (25.1 mN/m). Cationic surfactant (CTAB) slightly increased tension (25.4 mN/m) but aided MWCNT dispersion. Nonionic and anionic surfactants showed superior dispersing power, aligning with MWCNTs and enhancing dispersion. Thermogravimetric analysis (TGA) unveiled alterations in the thermal stability of epoxy-MWCNT nanocomposites induced by radiation, particularly evident at elevated doses (500 and 1000 kGy). Notably, surfactant-modified specimens exhibited discernible effects on various thermal stability parameters. DMA analysis revealed radiation-induced changes in viscoelastic properties. Unirradiated epoxy exhibited a Tg of 58 °C, while 250 kGy irradiation enhanced crosslinking (Tg: 64 °C). Higher doses (500 kGy, 1000 kGy) caused marginal Tg changes. Surfactant-modified samples showed varied effects, with Tween 80 emphasizing its role in phase separation. Results highlighted radiation's influence on stiffness and energy dissipation. Shape memory behavior indicated increased recovery time with higher doses, except at 250 kGy. Epoxy-MWCNT exhibited a stable recovery time, suggesting a MWCNT stabilizing effect. Fixation rates consistently reached 100%, indicating improved shape recovery influenced by MWCNTs and surfactants. This study provides insights into optimizing nanocomposites for satellite deployment applications. [ABSTRACT FROM AUTHOR]

To clarify the adsorption behavior of fluorocarbon surfactants on PMMA surfaces, the contact angles of two nonionic fluorocarbon surfactants (FNS-1 and FNS-2) and an anionic fluorocarbon surfactant (FAS) on polymethylmethacrylate (PMMA) surface were determined using the sessile drop method. Moreover, the effects of molecular structures on the surface tension, adhesion tension, solid–liquid interfacial tension, and adhesion work of the three fluorocarbon surfactants were investigated. The results demonstrate that the adsorption amounts for three fluorocarbon surfactants at the air–water interface are 4~5 times higher than those at the PMMA–solution interface. The three fluorocarbon surfactants adsorb on the PMMA surface by polar groups before CMC and by hydrophobic chains after CMC. Before CMC, FNS-2 with the smallest molecular size owns the highest adsorption amount, while FAS with large-branched chains and electrostatic repulsion has the smallest adsorption amount. After CMC, the three fluorocarbon surfactants form aggregates at the PMMA-liquid interface. FAS possesses the smallest adsorption amount after CMC. Besides, FNS-1 possesses a higher adsorption amount than FNS-2 due to the longer fluorocarbon chain and the lower CMC value of FNS-1. The adsorption behaviors of nonionic and anionic fluorocarbon surfactants on the PMMA surface are different. FAS forms interfacial aggregates before CMC, which may be attributed to the electrostatic interaction between the anionic head of FAS and the PMMA surface. [ABSTRACT FROM AUTHOR]

The conditions for the smart colorimetric determination of cetylpyridinium chloride and sodium dodecyl sulfate by reaction with Coomassie brilliant blue G (CBBG) have been proposed. The nature of the absorption and fluorescence spectra of aqueous solutions of CBBG as a function of acidity has been investigated. A variety of reagent forms and associations with ionic surfactants have been demonstrated. The composition of the associates formed in the CBBG–cationic surfactant system has been established. The increase in the analytical signal of the cationic surfactant and the stabilization of the colloid-chemical state of the system during reactions in the organized medium of the nonionic surfactant Triton X-100 has been demonstrated. These effects are realized through association in premicellar solutions and as a result of the solubilization of components in Triton X-100 micellar solutions. The addition of long-chain cationic surfactants to the reagent occurs with the replacement of the heteroatom proton. The absorption of CBBG–cationic surfactant associates solutions increases with the length of the cationic surfactant hydrocarbon chain. Ethanol additives decrease the aggregation of CBBG. The technique of cationic surfactant determination has been tested in the analysis of the pharmaceutical. The results show that the simplicity of analytical signal registration with satisfactory correctness and acceptably high sensitivity of determination is an advantage of the developed technique. [ABSTRACT FROM AUTHOR]

In this study, the lavender essential oil-incorporated polylactic acid (PLA) nanofibers were fabricated by the electrospinning technique with the presence of kolliphor as a nonionic surfactant. The FTIR spectra supported the chemical composition of the fibers. The FTIR spectra demonstrated that there is no chemical reaction present between PLA and lavender essential oil. The SEM images of all nanofibers showed bead-free morphology. ImageJ results showed that the average diameter of lavender oil-loaded fibers ranged between 121.6 ± 32 and 228.2 ± 53 nm. All lavender essential oil-incorporated nanofibers were hydrophobic with satisfactory thermal properties. Furthermore, the lavender essential oil-incorporated PLA nanofibrous mats exhibited good antioxidant activity. The results showed that as the concentration of the essential oil in resulting nanofibers increased, the antioxidant activity also increased. According to the results of this study, lavender essential oil-loaded PLA fibers can be considered for a wide range of potential applications such as active packaging, food coating, facial masks, and wound dressing. [ABSTRACT FROM AUTHOR]

Semi-volatile organic pollutants were found in most organic contaminated sites, especially in the industrial production of plastic and paint products, dismantling of electronic wastes, production of organic solvents, and chemical coatings. Electrokinetic remediation (EKR) was recognized as critical method to resolve the problem of organic pollutants separation and degradation. However, the low efficiency desorption and migration of organic pollutants was the main concerns during EK remediation. In this study, cyclododecane (CDD) was selected to investigate the process of electroosmotic flushing with anionic surfactant (sodium dodecyl sulfate, SDBS) and non-ionic surfactants (alcohol ethoxylate, AEO) for facilitating chemical desorption of low boiling point organic pollutants from soil. Simulated contaminated soil was subjected to treatment in an EK cell at 1 V/cm for 7 days. The experimental dependent variables, such as current, electroosmotic flow (EOF), pH, electrical conductivity (EC), and the concentration of CDD in the contaminated soil were continuously monitored. The results revealed that both current and EOF exhibited the trend of SDBS (13.74 mA, 350.9 mL) > water (8.22 mA, 285.7 mL) > AEO (6.12 mA, 124.3 mL). Furthermore, the removal efficiency of CDD by surfactants also followed this order with corresponding percentages of 90.87% and 90.01%. The soil pH near the cathode increased, and it caused alkalization trend of the flowing soil solution and improvement of CDD removal rate. Conversely, the lowest EC value was observed in the middle of the soil chamber. The highest overall CDD removal rate was achieved by employing a strategy of surfactant-assisted electrokinetic remediation, and approximately 90% CDD was transfered to the liquid phase. These findings contribute to our understanding of spatial and temporal variations in pollutant removal and the interplay between different electrokinetic variables during EK remediation. [ABSTRACT FROM AUTHOR]

Natural biopolymers become increasingly attractive as bio-based alternatives to petrol-based rheological modifiers, especially in personal care applications. However, many polysaccharides exhibit undesired properties in cosmetic applications such as limited viscosifying characteristics, unpleasant sensory properties, or incompatibility with certain formulation compounds. Here, a comprehensive rheological analysis of non-decorated acetan-like heteroexopolysaccharides derived from two Kozakia baliensis strains was performed in selected surfactant formulations. The results were compared to native xanthan gum and a genetically engineered xanthan variant, Xan∆ gumFGL , which lacks any acetyl- and pyruvyl moieties and whose rheological properties are unaffected by saline environments. All four polysaccharides displayed a highly similar rheological performance in the non-ionic surfactant lauryl glucoside, while the rheological properties differed in amphoteric and anionic surfactants cocamidopropyl betaine and sodium laureth sulfate due to minor changes in side chain composition. Polysaccharide precipitation was observed in the presence of the cationic surfactant. Nevertheless, the native heteroexopolysaccharide derived from K. baliensis LMG 27018 shows significant potential as a salt-independent rheological modifier compared to the genetically engineered Xan∆ gumFGL variant. In addition, blends of heteroexopolysaccharides from K. baliensis and several galactomannans displayed synergistic effects which were comparable to native xanthan gum-galactomannan blends. This study shows that heteroexopolysaccharides of K. baliensis are capable of further extending the portfolio of bio-based rheological modifiers. [ABSTRACT FROM AUTHOR]

Copyright of Oilfield Chemistry is the property of Sichuan University, Oilfield Chemistry Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Oilfield Chemistry is the property of Sichuan University, Oilfield Chemistry Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The Museum of Sun Yat-sen University houses a collection of antique glass slides dating back to the 1940s. These historical artifacts not only serve as a record of the past but also bring history to life. During extended storage, the emulsion layer on glass slides may harden and become brittle, leading to cracking and buckling. This study suggests a method to enhance the physical property of the emulsion layer by using a combination of nonionic surfactant isomeric alcohol ethoxylates eight (TO-8) and waterborne epoxy resin (WER). We investigated the microscopic action mechanism of the two on the emulsion layer of glass slides using scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), water contact angles, and other techniques. Our study revealed that TO-8 can significantly eliminate the spherulitic crystal structure of the emulsion layer, as well as improve its softness and hydrophilicity. The addition of the WER ensures that the cracking and warping of the emulsion layer film is fully corrected, resulting in a flat surface. Additionally, the size of the emulsion layer film remains stable even after wetting. The WER has minimal impact on the image information of glass slides. The emulsion layer of the glass slides, restored using the softening protection solutions developed in this study, showed almost full recovery of image information. This research holds significant theoretical and practical value for repairing cracked and warped emulsion layers on glass slides. [ABSTRACT FROM AUTHOR]

Triacontanol is a long-chain primary alcohol derived from policosanol, known for its diverse biological activities, including functioning as a plant growth regulator and exhibiting anti-inflammatory and antitumoral effects. However, its application is limited due to its high hydrophobicity, resulting in poor absorption and reduced therapeutic effectiveness. A potential solution to this problem is the use of niosomes. Niosomes are carriers composed of non-ionic surfactants, cholesterol, charge-inducing agents, and a hydration medium. They are effective in encapsulating drugs, improving their solubility and bioavailability. The objective of this study was to optimize and synthesize nano-niosomes for the encapsulation of triacontanol. Niosomes were synthesized using a thin-film hydration method combined with ultrasonication, following a Box–Behnken design. Niosomes were characterized using various techniques including dynamic light scattering, Fourier-transform infrared spectroscopy (FTIR), confocal microscopy, high-resolution scanning electron microscopy, and transmission electron microscopy (TEM). Formulation 14 of niosomes achieved the desired size, polydispersity index (0.198 ± 0.008), and zeta potential (−31.28 ± 1.21). FTIR analysis revealed a characteristic signal in the 3400–300 cm−1 range, indicating intermolecular interactions due to a bifurcated hydrogen bond between cholesterol and S60. Confocal microscopy confirmed the presence of triacontanol through Nile Red fluorescence. TEM revealed the spherical structure of niosomes. [ABSTRACT FROM AUTHOR]

Here we report on light-triggered generation of local flow utilizing a bio-compatible non-ionic photo-active surfactant. The mechanism is based on diffusioosmotic phenomenon, where the gradient of relative concentration with respect to different chemical species near a surface leads to an osmotic pressure gradient driving liquid flow along the surface. The application of a photo-responsive surfactant allows for easy and reversible changes in concentration gradient by positioning a light source at the desired place. Along with the so-inscribed concentration gradient one can change reversible the direction and strength of the flow even in a closed system. The phenomenology of light-driven diffusioosmotic flow (LDDO) can be used in a rather flexible way: colloids can be gathered or dispersed and bio-compatibility extends the range of colloid types also to living microorganisms such as soil bacterium Pseudomonas putida. We show that DO flow can be considered a versatile method to set hydrodynamic conditions along the sample for investigating the motility of living cells. Further advantages of employing LDDO are the flexibility of flow generation in a reversible way and with spatiotemporal control, without the need to either change the channel geometry by loading a different device, or the periphery of pumps and connectors. [ABSTRACT FROM AUTHOR]

Bicarbonate and CO2 are essential substrates for carboxylation reactions in bacterial central metabolism. In Staphylococcus aureus, the bicarbonate transporter, MpsABC (membrane potential-generating system) is the only carbon concentrating system. An mpsABC deletion mutant can hardly grow in ambient air. In this study, we investigated the changes that occur in S. aureus when it suffers from CO2/bicarbonate deficiency. Electron microscopy revealed that ΔmpsABC has a twofold thicker cell wall thickness compared to the parent strain. The mutant was also substantially inert to cell lysis induced by lysostaphin and the non-ionic surfactant Triton X-100. Mass spectrometry analysis of muropeptides revealed the incorporation of alanine into the pentaglycine interpeptide bridge, which explains the mutant's lysostaphin resistance. Flow cytometry analysis of wall teichoic acid (WTA) glycosylation patterns revealed a significantly lower α-glycosylated and higher ß-glycosylated WTA, explaining the mutant's increased resistance towards Triton X-100. Comparative transcriptome analysis showed altered gene expression profiles. Autolysin-encoding genes such as sceD, a lytic transglycosylase encoding gene, were upregulated, like in vancomycin-intermediate S. aureus mutants (VISA). Genes related to cell wall-anchored proteins, secreted proteins, transporters, and toxins were downregulated. Overall, we demonstrate that bicarbonate deficiency is a stress response that causes changes in cell wall composition and global gene expression resulting in increased resilience to cell wall lytic enzymes and detergents. [ABSTRACT FROM AUTHOR]

The influence of adding surfactants on the performance of high-solid anaerobic digestion of horticultural waste was extensively investigated in batch systems. Adding Tween series and polyethylene glycol series non-ionic surfactants had positive effects on biogas production, resulting in 370.1 mL/g VS and 256.6 mL/g VS with Tween 60 and polyethylene glycol 300 at a surfactant-to-grass mass ratio of 0.20, while the biogas production of anaerobic digestion without surfactants was 107.54 mL/g VS. The optimal and economically feasible choice was adding Tween 20 at a ratio of 0.08 g/g grass in high-solid anaerobic digestion. A kinetics model reliably represented the relationship between surfactant concentration and biogas production. The mechanism of surfactants working on lignocellulose was investigated. The improvement in high-solid anaerobic digestion by adding surfactants was attributed to the interaction between lignocelluloses and surfactants and the extraction of biodegradable fractions from the porous structure. An economic analysis showed that adding Tween 20 was likely to make a profit and be more feasible than adding Tween 60 and polyethylene glycol 300. This study confirms the enhancement in biogas production from horticultural waste by adding non-ionic surfactants. [ABSTRACT FROM AUTHOR]

To solve the bottleneck of low degradation rate and low biogas yield in anaerobic digestion of food waste, the addition of anionic surfactant sodium N-lauroylsarcosinate (SN) and nonionic surfactant primary alcohol ethoxylate (AEO) were proposed. The results showed that both surfactants could promote the methane production and facilitate the degradation of food waste. The highest methane yield per mass of volatile solid was obtained in 0.1 g/L AEO (497.14 mL) and 1 g/L SN (445.51 mL), which was improved by 92% and 72% compared with the control group. While with the increase of surfactant concentration, methane yield was decreased due to negative effect caused by the surfactant. This corresponded with the variation of pH, total volatile fatty acids (TVFAs), and soluble chemical oxygen demand (SCOD). The microbial community analysis showed that the relative abundance of methanobacterium increased while the relative abundance of methanosaeta decreased after the addition of surfactant. Meanwhile, the methane production pathway was shifted from codominance of hydrogenotrophic and aceticlastic methanogens to predominance by hydrogenotrophic methanogens in the groups with low concentration of AEO and SN. [ABSTRACT FROM AUTHOR]

Nano SiO2 particles (NPs) combined with organosilane surfactants present a promising avenue for the development of stable fluorine-free firefighting foams. In this study, hydrophilic nano SiO2 particles, non-ionic organosilane surfactant (SiCare2238), and amphoteric hydrocarbon surfactant (LAMC) were prepared as a mixed dispersion to investigate the interactions between nano particles and surfactants, foaming ability, and foam stability of the mixed dispersion. Results indicated that the surface activity, electrical conductivity, and foaming ability of the mixed dispersion decreased with increasing NPs concentration. The impact of NPs on foam stability depended on the filling and blocking mechanisms within the platform boundary of the formed liquid film. At NPs concentrations below 1.5%, strong electrostatic interactions among surfactant molecules resulted in the adsorption of surfactant molecules on the nano particle surface, preventing the formation of a network structure at the platform boundary, thereby reducing foam stability. At NPs concentrations above 1.5%, a significant number of NPs formed a network structure, filling and blocking the platform boundary, leading to delayed foam drainage, coarsening, and enhanced foam stability. This study provides theoretical guidance for the application of nano particles in fluorine-free. [ABSTRACT FROM AUTHOR]

Sucrose esters have been deployed as surfactants in many food products since the 1950s. In addition to their useful physical characteristics, sucrose esters also have interesting biological properties that enhance their utility. This review critically examines the broad suite of biological activities that has been attributed to both synthetically-derived and naturally-occurring sucrose esters. These include insecticidal, molluscicidal, plant growth-regulating, anti-microbial, anti-tumor, anti-oxidant, anti-depressive, neuro-protective, anti-inflammatory and anti-plasmodial effects. In addition to providing a summary of the structure-activity profiles of sucrose esters, the various known mechanisms-of action of these compounds are also discussed. Furthermore, since sucrose esters are well-known surfactants, the potential to advantageously apply their industrially desirable physical characteristics in combination with their biological properties is considered. Recent advances in synthetic chemistry that have facilitated the deployment of biologically active sucrose esters as food additives are also described. [ABSTRACT FROM AUTHOR]

[Display omitted] The formation of adducts via urea interaction with distinct classes of surfactants (cationic, anionic, nonionic, and zwitterionic), leading to their assembly into lamellar structures and subsequent formation of hydrogels. The characteristics of these hydrogels are associated with both, the length of the alkyl chain, and the specific head group of the surfactant molecules. Characterization of adduct formation was conducted using Wide-Angle X-ray Scattering (WAXS), while Small-Angle X-ray Scattering (SAXS) was employed to probe the subsequent assembly into lamellar structures. The kinetics of hydrogel formation were assessed through rheological measurements and observed thermal transitions utilizing Differential Scanning Calorimetry (DSC). The investigation revealed a universal propensity for hydrogel formation across all surfactant classes. The formation arises from the interactions between urea molecules via hydrogen bonding, forming adducts around the surfactant chains. In sequence, the adducts self-assemble in lamellae. This process constructs the intricate three-dimensional network characteristic of the hydrogel. Furthermore, the kinetics of hydrogel formation, and their rheological properties under equilibrated conditions, were found to be significantly influenced by the nature of the polar head group of the surfactant molecules. This is the first evidence on the formation of adducts of urea with classes of surfactants. As they are common components in cosmetic, supramolecular hydrogels have high potential to be used in formulations. [ABSTRACT FROM AUTHOR]

Solid silicon (Si) microneedles have many applications such as skin pretreatment to form micrometer-sized holes in the skin surface in transdermal drug delivery systems. Wet etching based on tetramethylammonium hydroxide (TMAH) is an efficient method to fabricate solid microneedles. However, it is challenging to increase the density of microneedle arrays due to the faster lateral etching than the vertical etching that requires a large initial mask size. In this work, we used wet etching based on TMAH to fabricate solid Si microneedles. One kind of nonionic surfactant, Triton X-100, was introduced into the TMAH solution to suppress the lateral etching. When Triton X-100 was added into TMAH for a given etching condition, the maximum height (attained right before the mask fell off) of microneedles could reach ∼230 μm for 600 μm square-shaped mask size and 700 μm array period, compared to microneedles of maximum 152 μm height for the same mask size and period without surfactant addition. Correspondingly, when the target heights of microneedles were the same as ∼230 μm, denser (down to 700 μm period, 600 μm mask size) microneedle arrays were achieved with the help of Triton X-100, in comparison to arrays down to 900 μm period (800 μm mask size) without surfactant addition. Furthermore, agitation by a magnetic stirring bar is important for the fabrication of dense solid Si microneedle arrays based on TMAH. The microneedle structures were rhombic pyramid in shape with Triton X-100 and agitation. But microneedle structures obtained with Triton X-100 yet without agitation were octagonal pyramid in shape with a much less steep side surface. [ABSTRACT FROM AUTHOR]

Selecting the appropriate surfactant as a foaming agent is crucial in the production of foamed concrete. In this study, multiple technological approaches were employed for the investigation of the effect of three different types of surfactants as foaming agents; the approaches included surface tension measurement, zeta potential analysis, spectrophotometry, and nanoindentation. The results showed that the surface activity, solution viscosity, and environmental pH all influenced the generation and stability of foam in foaming agents. The adsorption process of surfactants onto cement particles was complex and could be effectively explained using the double-layer theory. The adsorption of anionic surfactant molecules on cement particles significantly altered the zeta potential, up to −17 mV, with an adsorption efficiency over 10 times greater than that of cationic surfactants and more than 5 times greater than that of nonionic surfactants. Furthermore, after cement hardening, the mechanical properties of the resulting pores were notably improved due to the presence of adsorbed anionic surfactants, and the maximum compressive strength could exceed 10 MPa. [ABSTRACT FROM AUTHOR]

Cloud point extraction (CPE) has emerged as a highly promising method for the isolation and preconcentration of trace elements from beverages. By utilizing nonionic surfactants to form micellar structures that encapsulate analytes, CPE significantly enhances extraction efficiency and detection limits, often achieving improvements by several orders of magnitude. The optimization of CPE conditions, particularly the selection of surfactants and complexing agents, plays a crucial role in ensuring accurate analytical results. This review underscores the integration of CPE with spectrometric methods as a powerful approach for the separation, preconcentration, and quantification of numerous (ultra)trace elements across a wide range of beverages, including drinking water, wine, beer, juices, tea, and milk. The analytical potential of this integration is substantiated by the comprehensive examples listed in this paper, which include various strategies for sample preparation tailored specifically for different beverage types. While highlighting the effectiveness of conventional CPE methods, this review also emphasizes recent modifications and advancements in CPE techniques that further enhance their utility in beverage analysis. These advancements not only improve detection sensitivity but also align with the principles of green chemistry by reducing solvent consumption and energy requirements. [ABSTRACT FROM AUTHOR]

[Display omitted] Nonionic surfactant aerosols play a crucial role in many industries, but they can cause acute irritation to users' eyes during spraying. This cytotoxic process is associated with corneal cell necrosis causing cell membrane disruption. Industrial grade surfactants are typically polydisperse mixtures described by their nominal chemical structure but how the polydispersity affects their interactions with cell membrane, remains largely unexplored. A better understanding could benefit product formulations to maximise their efficiency whilst minimising their toxicity to the users. In this study, poly - oxyethylene glycol monododecyl ethers (C 12 E 4 , C 12 E 23) were used to form ideal binary surfactant mixtures. The cytotoxicities of mono and polydispersed surfactants towards human corneal epithelial cells were examined, followed by a series of biophysical characterisations of interactions between surfactants and model cell membranes. Notably, to probe the journey of individual C 12 E 4 and C 12 E 23 surfactant molecules across the cell membrane from a binary surfactant mixture, "two-colour" neutron reflection measurements were achieved via Hydrogen/Deuterium substitution. The relative distributions of C 12 E 4 and C 12 E 23 across cell membranes and their nanostructural conformations revealed a synergistic membrane-lytic ability initiated by surfactant mixing, with the more hydrophobic C 12 E 4 exhibiting stronger membrane binding potency than the hydrophilic C 12 E 23. The exact molar ratio of C 12 E 4 against C 12 E 23 in the mixture determined how the mixed surfactant interacted with the cell membrane, and how the process directly impacted cytotoxicity and eye irritation. Thus, the cytotoxicity of polydisperse surfactants is not the same as monodisperse surfactant of the same average structure. This work provides a useful basis for the assessment of surfactant mixing by balancing their efficiency and toxicity. [ABSTRACT FROM AUTHOR]

[Display omitted] Seeking effective ways to maintain cellular homeostasis is crucial to the survival of organisms when they encounter osmotic stress. Glycine betaine (GB) is a widely generated natural osmolyte, but its endogenous production and action are limited. Herein, a kind of nonionic surfactant dodecyl-β-d-glucopyranoside (DG) and a common polymer polyethylene glycol (PEG) are proven to have the ability to enhance the osmotic stress (induced by sugar concentration changes) tolerance of cell and organism models, those are giant unilamellar vesicles (GUVs) and gram-negative Escherichia coli. DG or PEG only induces small size decrease and certain shape change of GUVs. Importantly, DG or PEG at the concentration 100 times lower than that of GB effectively increases the survival rate of bacteria under both hypoosmotic and hyperosmotic conditions. This intriguing result is attributed to the insertion of DG or adsorption of PEG in the lipid bilayer membrane, leading to enhanced membrane permeability. These exogenous substances can replace GB to facilely and highly efficiently augment adaptation of organisms to osmotic stress. [ABSTRACT FROM AUTHOR]

[Display omitted] • Tween 80 additive modifies the solvation structure of Zn2+ ions. • Tween 80 additive reconstructs the hydrogen bond network in ZnSO 4 electrolyte. • Zn2+ ions complexed with Tween-80 create a protective hydrophobic layer. • Dual-layer Tween-80 on Zn anode prevents corrosion, reduces hydrogen evolution. Zinc metal anodes encounter significant challenges, including dendrite growth, hydrogen evolution, and corrosion, all of which impede the rate capability and longevity of aqueous zinc-ion batteries (AZIBs). To effectively tackle these issues, we introduced Tween-80 into the traditional ZnSO 4 electrolyte as an additive. Tween-80 possesses electronegative oxygen atoms that enable it to adsorb onto the zinc (Zn) anode surface, facilitating the directional deposition of Zn metal along the (0 0 2) orientation. The hydroxyl and ether groups within Tween-80 can displace some of the coordinated water molecules in the Zn2+ inner solvation shell. This disruption of the hydrogen bond network regulates the solvation structure of Zn2+ ions and suppresses the possibility of hydrogen evolution. Moreover, the long hydrocarbon chain present in Tween-80 exhibits excellent hydrophobic properties, aiding in the resistance against corrosion of the Zn anode by water molecules and reducing hydrogen evolution. Consequently, a symmetric cell equipped with the Tween-80 additive can cycle stably for over 4000 h at 1 mA cm−2 and 1 mA h cm−2. When paired with the V 2 O 5 cathode, the full cell demonstrates a high-capacity retention rate exceeding 80 % over 1000 cycles at a current density of 2 A g−1. This study underscores the advantages of utilizing non-ionic surfactants for achieving high-performance aqueous zinc-ion batteries. [ABSTRACT FROM AUTHOR]

[Display omitted] In order to understand the basic mechanisms affecting emulsion stability, the intrinsic dynamics of the drop population must be investigated. We hypothesize that transient ballistic motion can serve as a marker of interactions between drops. In 1G conditions, buoyancy-induced drop motion obscures these interactions. The microgravity condition onboard the International Space Station enable this investigation. We performed Diffusing Wave Spectroscopy (DWS) experiments in the ESA Soft Matter Dynamics (SMD) facility. We used Monte Carlo simulations of photon trajectory to support data analysis. The analysis framework was validated by ground-based characterizations of the initial drop size distribution (DSD) and the properties of the oil/water interface in the presence of surfactant. We characterized the drop size distribution and found to be bi-disperse. Drop dynamics shows transient ballistic features at early times, reaching a stationary regime of primarily diffusion-dominated motion. This suggests different ageing mechanisms: immediately after emulsification, the main mechanism is coalescence or aggregation between small drops. However at later times, ageing proceeds via coalescence or aggregation of small with large drops in some emulsions. Our results elucidate new processes relevant to emulsion stability with potential impact on industrial processes on Earth, as well as enabling technologies for space exploration. [ABSTRACT FROM AUTHOR]

The impacts of inadequate disposal of industrial wastewater cause environmental, economic, social and human health damage. The search for innovative and viable methodologies from a technical and economic standpoint aims to promote suitable management of effluents produced by different industrial activities. The objective of this paper was to study phenol, aromatic alcohol and aromatic amine removal using cloud point extraction based on analysis of extraction capacity, miscibility curves, equilibrium lines, distribution coefficients and mass transfer solubilisation diffusion. The oxo-C10E3P4E2 surfactant produced the best results, exhibiting smaller coacervate volume fractions, low concentration in the diluted phase and efficient extraction (E%) of phenol (81.79%), 1-phenylethanol (67.88%), 2-phenylethanol (65.41%), benzyl alcohol (57.01%), aniline (56.91%), p-toluidine (73.96%) and 2,4-dimethylaniline (84.87%). The ternary phase diagrams revealed a large miscibility area favourable to extraction, with equilibrium lines showing a pronounced slope in favour of the coacervate, indicating high compound concentration factors. Equilibrium isotherms were used to obtain the distribution and solubilisation constants (Log KC/D KS), in the following order: aniline (1.05; 9.15) < p-toluidine (1.35; 20.40) < 2,4-dimethylaniline (1.76; 45.10) and benzyl alcohol (1.07; 8.19) < 2-phenylethanol (1.22; 14.04) < 1-phenylethanol (1.28; 15.23) < phenol (1.59; 36.72). These parameters show a linear correlation with Log KO/W, revealing that micellar solubilisation is governed by the hydrophobic nature of aromatic organic compounds. The evolution of pH demonstrated that the ionised forms of phenol and 2,4-dimethylaniline do not establish interactions (electrostatic, van der Waals, hydrogen bonds) with surfactants. Mass transfer diffusion is governed by hydrophobic compounds, slightly compromising phenol due to its high solubility in water. [ABSTRACT FROM AUTHOR]

[Display omitted] Hypothesis: Limited research has been conducted on the influence of chelating agents on the self-assembly process in surfactant solutions. The traditional approach assumes the chelating agent only interferes as a salting-out ion, therefore promoting surfactant separation. However, the opposite behavior has been observed for iminodipropionate based surfactants, in which the presence of chelating agents of the aminopolycarboxylate type increases solubility of nonionic ethoxylated surfactants in mixed micellar systems. Specific interaction between chelating agents-surfactants can be an important parameter in the self-assembly processes. Experiments: Physicochemical properties of solutions containing amphoteric surfactant and tetrasodium glutamatediacetate have been investigated. Macroscopic properties, such as viscosity and cloud point, were evaluated in the presence of a non-water-soluble alkyl ethoxylated surfactant. Interactions between amphoteric surfactant and chelating agent were monitored by NMR spectroscopy, including 13C chemical shift and lineshape analysis as well as 1H diffusometry. Findings: The study reveals that there is an interaction between the head group of the surfactant and the chelating agent forming oligomeric surfactant analogues with larger hydrophilic moieties, which results in smaller, more spherical micelles. The combined interactions provide possibilities for tuning the aggregation behavior of systems containing surfactants and chelating agents, and with that, the macroscopic properties of the system. [ABSTRACT FROM AUTHOR]