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Microemulsions are thermodynamically stable colloidal dispersions formed in an oil-water environment with the help of surfactants. They are transparent or translucent, isotropic, and have a small droplet size, typically 10 to 100 nanometers. In the pharmaceutical industry, microemulsions are often used to enhance the solubility of poorly soluble drugs. Many drugs have low aqueous solubility, leading to poor bioavailability and reduced therapeutic efficacy. However, when formulated as microemulsions, these drugs can be solubilized in the oil-water interface of the microemulsion system, resulting in a significant increase in their apparent solubility. The small droplet size and large interfacial area of microemulsions provide an ideal environment for incorporating hydrophobic drugs, as the drug molecules can be accommodated in the hydrophobic core of the micelles or droplets. This solubilization makes the drug more readily available for absorption in the body, thereby improving its bioavailability. As thermodynamically stable colloidal dispersions, microemulsions have gained significant attention due to their unique properties and versatile applications. This review paper aims to provide a comprehensive overview of microemulsions with respect to its patentability arena, delving into nuanced aspects that have not been extensively covered in prior review articles. We address key unanswered questions in the existing literature, offering fresh perspectives and insights. Our analysis encompasses the latest advancements in microemulsion research, highlighting novel applications, formulation strategies, emerging trends, market potential of microemulsion as well as its future scope in the pharmaceutical industry. [ABSTRACT FROM AUTHOR]

In recent perovskite solar cell (PSC) research, copper(I) thiocyanate (CuSCN) is an emerging inorganic hole transport layer (HTL) due to its suitable band gap, matched band edge positions with the perovskite and high stability under ambient conditions. However, being a coordination polymer typically requires sulfide‐based solvents that strongly interact with Cu(I) for dissolution. Dipropyl sulfide (DPS) is generally used where it is very sparingly soluble of about 10–12 mg mL−1, which leads to low surface coverage with pin‐holes on the surface responsible for the generation of defects at the perovskite–HTL interface. In this study, addition of the optimized amount 100 μL of co‐solvent Acetonitrile (ACN) increased the CuSCN dissolution from 10 to 35 mg mL−1. ACN can act as a Lewis‐base making it capable of donating electrons to a Lewis‐acid like Cu+ from CuSCN. ACN is a polar aprotic solvent due to its highly polar CN bond and by adding CuSCN the dipole–dipole interactions can stabilize the CuSCN molecules in solution. The device with architecture (FTO/c‐TiO2/mp‐TiO2/MAPbI3/CuSCN/carbon) showed the higher power conversion efficiency (PCE) of ≈11% with Voc of 1.01 V and Isc 24.65 mA cm−2 showing excellent stability stored under ambient atmosphere which retains 80% of its initial efficiency after 10 days. [ABSTRACT FROM AUTHOR]

The study investigates the influence of various catalysts (Ni/TiO2, Co/TiO2, and Zeolite) on the hydrothermal liquefaction of microalgae and explores the effect of co-solvents (acetone, methanol, and toluene) on biocrude yield from different microalgae three species namely Nannochloropsis oculata, Chlorella vulgaris, and Spirulina maxima. Catalyst characterization using FESEM, XRD, and BET analysis revealed distinct properties. Under Co-TiO2, Nannochloropsis oculata and Chlorella vulgaris yield 56.21% and 57.6% biocrude at 5% loading; Spirulina maxima yields 45.3% at 2.5% loading. With Ni-TiO2, Nannochloropsis oculata yields 52.4% at 2.5% loading; Chlorella vulgaris yields 44.7% at 5%; Spirulina maxima yields 44% at 2.5% loading. Zeolite yields: Spirulina maxima and Chlorella vulgaris yield 53.8% and 52.1% at 2.5%; Nannochloropsis oculata yields 48.3% at 7.5% loading. Co-solvent addition significantly boosts biocrude yield; methanol and toluene yield 53.7% and 49.2% for Chlorella vulgaris and Spirulina maxima, respectively, while acetone yields 57.6% for Nannochloropsis oculata. Different solvents extract diverse functional groups such as alkanes, halides, aromatics, and aldehydes which has wide industrial applications. [ABSTRACT FROM AUTHOR]

The Green Deal targets, along with tightening emissions legislation, foster research on alternative propulsion systems. In non-road mobile machinery (NRMM), these efforts largely rally around sustainable fuels while keeping the benefits of energy security (multi-fueling) high. In this context, the blends of Hydrogenated Vegetable Oil (HVO) and Methanol (MEOH) are amongst the most promising yet under-researched alternatives and, as such, need dedicated methods for determining their suitability in engine applications. In this paper, we evaluate the feasibility of Fourier transform infrared (FTIR) analytics for determining the stability of MEOH-HVO mixtures. The research considers temperature effects during storage by conditioning the test samples at −20 °C and +20 °C. The stability of the blends and different co-solvents is analysed after six weeks, and FTIR spectra are used to identify the chemical bonds. From FTIR analysis, blending MEOH20 with 1-dodecanol results in stable homogenous alkyl-ether fuels, while the MEOH20 blend with methyl-butyrate results in ester fuels. There are observable differences in the blend samples according to their storage temperatures. In conclusion, both fuel blend samples formed different fuel types, which are stable and homogenous at room temperature, posing great potential for their applicability in different NRMM types. [ABSTRACT FROM AUTHOR]

Approximately 25% of global carbon emissions come from food production. Renewable fuels are crucial for curbing greenhouse gas (GHG) emissions from vehicles, non-road machines, and agricultural machinery. Tractors, key to modern farming, are central to these efforts. As agriculture strives for sustainability, alternative fuels like methanol and hydrotreated vegetable oil (HVO) are arousing interest because they are renewable and offer potential for blending for use in diesel engines. Methanol and HVO have limited solubility in direct mixing, so the addition of a co-solvent is essential. This study addresses the research gap regarding the properties of HVO and methanol blends with co-solvents. It investigated the impact of three co-solvents, 1-dodecanol, 1-octanol, and methyl butyrate, on the miscibility of HVO and methanol. The experimental measurements cross-varied the co-solvent type with different blending ratios (MeOH5 and MeOH10). Investigated parameters include fuel density, kinematic viscosity, distillation properties, and surface tension. The co-solvents enabled the formation of a singular, clear, and homogeneous phase in methanol-HVO blends. The co-solvent 1-dodecanol demonstrated the highest solubilizing capacity for MeOH5 and MeOH10 blends, followed by 1-octanol. Adding co-solvents led to increased fuel density, decreased kinematic viscosity, and small changes in surface tension. These findings contribute to the optimization of methanol–HVO fuel blends for efficient and environmentally friendly use in vehicles, non-road machinery, and agricultural machinery. [ABSTRACT FROM AUTHOR]

Methanol and hydrotreated vegetable oil (HVO) are complementary in the context of achieving ultra-low emission levels via low temperature combustion. HVO is a high-quality fuel fully compatible with compression ignition engines. Standalone methanol combustion is relatively straight-forward according to the Otto principle, with a spark ignited or in conventional dual-fuel ("liquid spark") engines. These two fuels have by far the largest reactivity span amongst commercially available alternatives, allowing to secure controllable partially premixed compression ignition with methanol–HVO emulsification. This study investigates the corrosion of aluminum, carbon steel, stainless steel, and a special alloy of MoC210M/25CrMo4+SH, exposed to different combinations of HVO, HVO without additives (HVOr), methanol, and emulsion stabilizing additives (1-octanol or 1-dodecanol). General corrosive properties are well determined for all these surrogates individually, but their mutual interactions have not been researched in the context of relevant engine components. The experimental research involved immersion of metal samples into the fuels at room temperature for a duration of 60 days. The surfaces of the metals were inspected visually and the dissolution of the metals into fuels was evaluated by analyzing the fuels' trace metal concentrations before and after the immersion test. Furthermore, this study compared the alterations in the chemical and physical properties of the fuels, such as density, kinematic viscosity, and distillation properties, due to possible corrosion products. Based on these results, methanol as 100% fuel or as blending component slightly increases the corrosion risk. Methanol had slight dissolving effect on aluminum (dissolving Al) and carbon steel (dissolving Zn). HVO, HVOr, and methanol–HVOr–co-solvents were compatible with the metals. No fuels induced visible corrosion on the metals' surfaces. If corrosion products were formed in the fuel samples, they did not affect fuel parameters. [ABSTRACT FROM AUTHOR]

Manganese hexacyanoferrate (MnHCF) is one of the most promising cathode materials for aqueous battery because of its non‐toxicity, high energy density, and low cost. But the phase transition from MnHCF to Zinc hexacyanoferrate (ZnHCF) and the larger Stokes radius of Zn2+ cause rapid capacity decay and poor rate performance in aqueous Zn battery. Hence, to overcome this challenge, a solvation structure of propylene carbonate (PC)‐trifluoromethanesulfonate (Otf)‐H2O is designed and constructed. A K+/Zn2+ hybrid battery is prepared using MnHCF as cathode, zinc metal as anode, KOTf/Zn(OTf)2 as the electrolyte, and PC as the co‐solvent. It is revealed that the addition of PC inhabits the phase transition from MnHCF to ZnHCF, broaden the electrochemical stability window, and inhibits the dendrite growth of zinc metal. Hence, the MnHCF/Zn hybrid co‐solvent battery exhibits a reversible capacity of 118 mAh g−1 and high cycling performance, with a capacity retention of 65.6% after 1000 cycles with condition of 1 A g−1. This work highlights the significance of rationally designing the solvation structure of the electrolyte and promotes the development of high‐energy‐density of aqueous hybrid ion batteries. [ABSTRACT FROM AUTHOR]

This study aimed to develop an efficient method for converting residual biomass into biofuel through a process that combines supercritical fluid extraction and hydrothermal liquefaction. The study analyzed the compositional changes in the biomass residues using various co-solvents and assessed their potential for biofuel production. After hydrothermal liquefaction, the liquid biofuel produced showed a decrease in the H to C ratio from 1.7 to 1.6 and a reduction in the O to C ratio from 0.5 to 0.2, compared to the unprocessed feedstock, indicating a favorable alteration in elemental composition for biofuel production. Notably, residues extracted with supercritical CO 2 and ethanol had the lowest yield, while those extracted with CO 2 and water achieved the highest energy recovery at 101.5 %. These findings suggest that integrating supercritical fluid extraction with hydrothermal liquefaction is an environmentally sustainable and efficient approach, significantly advancing the development of sustainable biofuels. [Display omitted] • Co-solvent in supercritical extraction affect the quality of biofuel from residue. • The residue using a co-solvent of water showed the highest energy recovery. • Integration of extraction and liquefaction can maximize the usage of biomass. [ABSTRACT FROM AUTHOR]

Low‐dimensional nanostructures of halide perovskites have been receiving extensive research interest for their superior optical, electrical, and stability characteristics over their conventional bulk counterparts. In particular, the unique surficial characteristics of well‐defined 1D nanowires have shown high feasibility for high performance optoelectronic applications. The key aspect of endorsing this nanoscale form factor in practical applications lies in securing dimensional uniformity and controllability in large scales, which generally requires complicated lithographic procedures. In this work, a simple, rapid, and widely applicable strategy for the direct synthesis and printing of well‐aligned nanowire arrays on a large scale is demonstrated. By employing blade coating methods with sophisticatedly controlled stick‐slip motions, periodically resolved transverse 3D meniscus enables uniform directional growth of highly crystalline CsPbI3 nanowires without the need for templates. A systematic investigation of morphological evolutions with respect to kinetic processing variables is conducted, along with a comprehensive suite of structural and optical analyses for the synthesized nanowire arrays. A single nanowire photodetector is employed to demonstrate the superiority and applicability of the fabrication strategy. Finally, a 2D image recognition is demonstrated by using an array of photodetectors fabricated via a fast (<2 min) direct printing of nanowire arrays on wafers. [ABSTRACT FROM AUTHOR]

[Display omitted] • Seven different natural deep eutectic solvents (NADES) were obtained. • The NADES were investigated as co-solvents that enhancing metronidazole (MNZ) solubility. • Choline chloride-citric acid NADES enhanced the solubility of MNZ most efficiently. • The dominating interactions between MNZ and the co-solvent were hydrophilic-hydrophobic and hydrophobic-hydrophobic. This research aimed to explore the utility of natural deep eutectic solvents (NADES) as the co-solvents for slightly water-soluble metronidazole (MNZ). After testing 70 wt% (percentage by weight) aqueous mixtures of seven NADESs, it was found that MNZ had the highest solubility in water solutions of NADES composed of choline chloride (ChCl) and citric acid (CA). The solubility of MNZ (expressed as 103 mol fraction) increased with the concentration of ChCl:CA NADES (from 6.7743 to 26.8518 at 298.5 K, for 30 and 70 wt% NADES-water mixtures, respectively), and it was more effective when compared to aqueous solutions of individual NADES components with wt% corresponding to these in the NADES-water mixtures. The study also found a preferable mixing of MNZ with aqueous solutions of NADES reflected by negative values of standard molar enthalpy change of mixing (approx. − 4.2 kJ·mol−1), compared with positive values in the case of MNZ mixing with water or ChCl aqueous solutions (approx. 7.3 kJ·mol−1). Comparative research conducted on the volume and acoustics of MNZ in water and aqueous solutions of ChCl, CA, and ChCl:CA NADES also confirmed stronger interactions between the drug and NADES and CA. The dominant interactions between MNZ and co-solvent were hydrophilic-hydrophobic and hydrophobic-hydrophobic. This effect increased in the following strength order: ChCl < NADES < CA. In conclusion, the obtained NADES seems to be a promising co-solvent which provides solid grounds for further research to evaluate the full potential in pharmaceutical design of MNZ liquid formulations. [ABSTRACT FROM AUTHOR]

The replacement of current organic chemical processes with more environmentally benign alternatives is an important goal from an ecological point of view. The study is aimed with the goal of promoting water as a solvent in organic synthesis. In recent years, extensive industrial and scholarly research has been promoted for the development of organic reactions in aqueous media. Using water as a solvent often promotes considerable rate enhancements and operational simplicity. Environmental benefits of using water are additionally highlighted in relation to the Twelve Principles of Green Chemistry. [ABSTRACT FROM AUTHOR]

[Display omitted] • Zr-HY is an excellent catalyst for the cascade reaction. • Hydrophobicity and cosolvents significantly accelerate the title reaction. • Ratio of open:closed Zr sites higher in Zr-HY than Zr-Beta. • IR of sorbed 2-pentanol probes hydrophobic/hydrophilic environment. Trans -anethole is an important ingredient in many flavors, fragrances and pharmaceutical formulations. Heterogeneous catalysis provides the opportunity for its green synthesis from 4′-methoxypropiophenone via a cascade of Meerwein-Ponndorf-Verley reduction followed by dehydration. Zr-containing zeolites were especially active catalysts. Surprisingly, Zr-HY was more active than Zr-Beta or mesoporous Zr-MSU. The effect of pore size, hydrophobicity and co-solvent has been investigated. Pyridine poisoning revealed that weak Lewis acid sites can catalyze the MPV reduction but stronger acid sites are required for the dehydration. The hydrophobicity and the ratio of open/closed Zr sites were higher for Zr-HY than Zr-Beta. Adding a moderately polar co-solvent like p -xylene more than doubled the reaction rate compared to only 2-pentanol as solvent. For an efficient cascade reaction, a hydrophobic catalyst with large micropores is required which combines hydrogen transfer and dehydration activities, together with an inert co-solvent that balances the concentration of both substrates inside the zeolite. [ABSTRACT FROM AUTHOR]

To overcome the chemical inertness of CO2, one strategy consists of pre‐activating or destabilizing it, to lower the reduction barrier, by preparing a carbene‐CO2 compound where the CO2 is bent rather than linear. This pre‐activation has been studied in ionic liquids (IL) based on imidazolium as a cation with different anions under conditions of mild pressure, room temperature and UV/Vis light. This screening showed that only 1‐butyl‐3‐methyl‐imidazolium acetate (C1C4ImOAc) was capable of effectively pre‐activating CO2 by chemical sorption to give a more reactive 1‐butyl‐3‐methyl‐imidazolium‐2‐carboxylate (C1C4ImCO2) species. A co‐solvent can be used to consume the photo‐generated holes in Pd/g‐C3N4 as a sacrificial agent but also to provide the protons necessary to reduce CO2. In this study, the influence of several type of co‐solvents such as H2O, isopropanol (iPrOH), and 1‐(2‐hydroxyethyl)‐3‐methyl imidazolium bis(trifluoromethanesulfonyl)imide [C1C2(OH)ImNTf2], has been tested on the activation of CO2 in C1C4ImOAc. We first defined the optimal molar ratio of co‐solvent to be used in order not to compromise CO2 pre‐activation for subsequent application in CO2 transformation. Photocatalytic reductions of CO2 to CO on Pd/g‐C3N4 by varying different parameters demonstrated that CO2 pre‐activation in a mixture of C1C4ImOAc and isopropanol was the most efficient to consider a prospective strategy of CO2 photoreduction in an IL medium. [ABSTRACT FROM AUTHOR]

[Display omitted] • The extraction yields are shown to depend on cerium salt concentration. • Using a co-solvent and water in wide proportion lead to some extraction yields up to 82%. • The structure coupled with the thickness of the deposits explain the extraction efficiency. The extraction of cerium from cotton substrate, as a matrix model, using supercritical CO 2 modified with phosphorus extractant and co-solvent/water in wise proportions, has been investigated. Using a recently developed isobutyl amidophosphonate extractant, the aim of this study was to emphasize how besides the usually considered operating parameters (flow rate, pressure and temperature), the efficiency of supercritical CO 2 extraction of cerium depends on the concentration of cerium nitrate deposits on the substrate (between 0.27 and 261 mg g cotton −1) and on the presence and composition of co-solvent/water mixture as well. The variations of the extraction efficiency with the nature of the Ce nitrate deposits (aggregates or homogenous layers) are explained by using a deposition model confirmed using SEM and coupled with SAXS data. Extraction is promoted when Ce nitrates deposits are in the form of segregated aggregates instead of homogeneous layers. Phase equilibrium data for CO 2 -ethanol-amidophosphonate and CO 2 -isopropanol-amidophosphonate ternary systems have been measured at 40 °C and 25 MPa to investigate the benefit of using a co-solvent. Extraction experiments show that adding a co-solvent and carefully adjusting the water concentration up to 30%wt are crucial to obtain high mass extraction yields, here up to 82%. [ABSTRACT FROM AUTHOR]

The use of cosolutes and high hydrostatic pressure has been described as an efficient means to modulate the stability of enzymes and their catalytic activity. Cosolvents and pressure can lead to increased reaction rates without compromising the stability of the enzyme. Inspired by the multi‐component nature of the crowded cellular milieu of biological cells of piezophiles, we studied the combined effects of macromolecular crowding agents, different types of cosolvents and pressure in concert on a hydrolysis reaction catalyzed by α‐chymotrypsin. We have seen that crowding agents and cosolvents can have very diverse effects on enzymatic activity. Addition of the deep‐sea osmolyte trimethylamine‐N‐oxide displays by far the most positive effect on the catalytic efficiency, keff, of the reaction, which is even markedly enhanced at high pressures. Addition of the chaotropic agent urea leads to the reverse effect, and PEG and dextran as two representative crowding agents of a different nature show nearly similar values for keff compared to the pure buffer data. Such information may not only be relevant for understanding life processes in extreme environments, but also for the use of enzymes in industrial processing, which often requires harsh conditions as well. [ABSTRACT FROM AUTHOR]

Different physicochemical and biological treatments have been used to treat oil sludges, and oil recovery techniques are preferred such as oil sludge washing (OSW) with surfactants and co-solvents. Toluene is commonly used as co-solvent, but it is non-benign to the environment. This study tested alternative co-solvents (n-pentane, n-hexane, cyclohexane, and isooctane) at 1:1 and 2:1 C/OS (co-solvent to oil sludge ratio). Also, this study evaluated the effect on the oil recovery rate (ORR) of three main parameters in the washing: type, concentration, and application ratio (S/OS) of surfactants to oil sludges. To date, no study has assessed these parameters in the washing of oil sludges from different sources. Four types of oil sludges and five surfactants (Triton X-100 and X-114, Tween 80, sodium dodecyl sulphate (SDS), and rhamnolipid) were used. The results showed that cyclohexane had high ORR and could be used instead of toluene because it is more benign to the environment. The S/OS ratio had a high effect on the ORR and depended on the type of oil sludge. Rhamnolipid, Triton X-100, and Triton X-114 had the highest oil recovery rates (40 – 70%). In addition, it was found that the surfactant concentration had no effect on the ORR. Consequently, the addition of surfactant was not significantly different compared to the washing with no surfactants, except for one sludge. The use of the surfactant in the washing solution can help in the selective extraction of specific oil hydrocarbon fractions in the recovered oil to assess its potential reuse as fuel. Further recommendations were given to improve the OSW process. [ABSTRACT FROM AUTHOR]

• The differences in interaction strength between AOEMIMTFSI and DMSO/CH 3 OH/CH 3 CN are described in detail. • The changes of hydrogen bonding interactions was unveiled. • Several complexes were assigned by excess spectra. Scientific research has witnessed an increasing fascination with ester-functionalized ionic liquids in recent years. These ester-functionalized ionic liquids are particularly attractive due to their superior biodegradability and potential applications, which surpass those of traditional ionic liquids. In actual use, it is common to blend these ionic liquids with co-solvents. However, there is currently a lack of research on the structures and interaction mechanisms of these mixtures. In this work, the hydrogen bonding interactions and microstructures of 1-acetoxyethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide (AOEMIMTFSI) with various polar co-solvents (DMSO, CH 3 OH, CH 3 CN) were researched by combining infrared experiments and DFT calculations. The finding are as follows: (1) O atom in [TFSI]− primary interacts with C2−H in [AOEMIM]+, while the O or N atom in the co-solvents (DMSO, CH 3 OH, CH 3 CN) primarily interact with C4,5−H in [AOEMIM]+. (2) With the addition of co-solvents (DMSO‑ d 6 , CD 3 OD or CD 3 CN), the hydrogen bonding interactions associated with the v (imidazolium C−H) in the AOEMIMTFSI−DMSO‑ d 6 /CD 3 OD/CD 3 CN systems are strengthened. (3) The hydrogen bonding interactions between AOEMIMTFSI and DMSO are the strongest, followed by those between AOEMIMTFSI and CH 3 OH, while the hydrogen bonding interactions between AOEMIMTFSI and CH 3 CN are the weakest. (4) 2[AOEMIM]+[TFSI]−, 2[AOEMIM]+[TFSI]−−co-solvent, [AOEMIM]+[TFSI]−−co-solvent and [AOEMIM]+−co-solvent complexes were assigned through the analysis of excess spectra. [ABSTRACT FROM AUTHOR]

[Display omitted] • The superbase-derived ionic liquid/co-solvents facilitated cellulose dissolution. • The improved electrospinnability of cellulose solutions enabled a continuous jet. • The electrospinning process was optimized to reduce adhesion between filaments. • The cellulose nanofibers exhibited excellent thermal stability and hydrophilicity. Ionic liquids (ILs), well-known for their wide solubility, low volatility, and high chemical stability, can be an excellent alternative to volatile solvents commonly employed in micro/nanofiber fabrication. Herein, nanofibers were successfully fabricated through electrospinning of natural cellulose, which realized by a novel superbase-derived ionic liquid (SIL) complemented with dipolar aprotic solvents as co-solvents. The SIL/co-solvent systems with enhanced hydrogen-bonding basicity (>1.30) accelerated cellulose dissolution. Besides, the improved transport properties of SIL/co-solvent systems facilitated small ion clusters and free ions deeper penetration into the hierarchical cellulose structures, synergistically contributing to a high rate of cellulose dissolution. Furthermore, the solution electrospinnability systematically explored and the electrospinning process was optimized to achieve a continuous jet and minimize adhesion between wet filaments. Consequently, cellulose nanofibers with a diameter range of 100–500 nm were produced stably. The resulting nanofiber nonwoven mat featuring mesopores of about 20.15 nm exhibited excellent thermal stability (the maximum decomposition temperature: 343 °C), exceptional hydrophilicity (15°), and high porosity (67.78 %). This study provides an efficient approach for fabricating high-performance cellulose nanofibers, which hold significant potential for the preparation and application of environmentally friendly, sustainable, and functional cellulose-based materials such as mask filter layers and battery separators. [ABSTRACT FROM AUTHOR]

Mixed micellar behavior of a series of m -2- m cationic gemini surfactants (where m = 10, 12 and 14) with monomeric surfactants (dodecyltrimethylammonium bromide, tetradecyltrimethyl-ammonium bromide and cetyltrimethylammonium bromide) has been studied in aqueous and in aqueous n-propanol, n-butanol, tertiary butanol, propylene glycol and glycerol solutions using conductivity, surface tension, viscosity and dynamic light scattering techniques at 298.15, 308.15 and 318.15 K, respectively. In mixtures of 10–2–10 with monomeric surfactants, the synergistic interactions increase with the chain length of monomeric surfactants whereas the mixtures with 12–2–12 and 14–2–14 exhibit the opposite trends. However, the synergistic interactions decrease with the increase in temperature of all the mixtures. The thermodynamic and surface parameters have been evaluated and the influence of the variations in hydrophobic chain length of the surfactants and the type of the co-solvent on these parameters has been discussed. The hydrodynamic diameter increases with the chain length of the surfactants. [ABSTRACT FROM AUTHOR]

The scope of the work carried out is aimed to evaluate the effects of blending methanol in the gasoline pool, particularly octane number and Reid vapor pressure increase when methanol is substituting methyl-tertiary-butyl ether in the formulation of Regular and Premium base gasolines. Isopropyl alcohol and ethanol have been investigated and found to be a promising co-blending alcohol to be mixed in gasoline methanol blends. Isopropyl alcohol is most effective below 3 vol%. Ethanol has been found to be the most promising co-blending alcohol able to reduce the Reid vapor pressure increase by 1.4 psi even with concentrations in the range of 2 vol%. The addition of isopropyl alcohol to the methanol–gasoline blends has shown the ability of a ternary mixture to further reduce the Reid vapor pressure of the finished gasoline and, subject to availability and price of isopropyl alcohol, could be of interest in further formulation studies focused on maximizing the saving on finished gasoline cost by reducing the Reid vapor pressure of base gasoline and/or increasing the methanol content. [ABSTRACT FROM AUTHOR]

This work describes a simplified method developed for calculating the Hansen parameters (HSPs) for scCO2-polar modifier solvent mixtures. The method consists in fitting 2nd order equations on the calculated values of HSPs of pure components in function of pressure and temperature. It has been proved that these equations are suitable for the characterization of the above system. The current work also proposes a modified representation method, which eliminates the shortcomings of the original ternary Teas diagram, normally used for the representation of the Hansen parameters. On the one hand, the Teas diagram uses quantities without any physical meaning and, on the other hand, the illustration of the solubility information is distorted because it does not take into account the differences of the Hildebrand parameters of different solvents. The factors we have chosen to represent on the ternary diagram possess physical meaning (cohesion energy density partitions). The distortion was eliminated by extending the Teas diagram to a prismatic three dimensional representation. We proved that the Hansen-ellipsoid from the Cartesian coordinate system (dd = f (δH, dp)) is transformed in an ellipsoid also in the new coordinate system (the transformation is pseudo-isomorphic). Nonetheless, the suggested corrections improve the accuracy of the Hansen method, in some cases the interactions between the solvents and the dissolved materials are still not predicted with sufficient accuracy. Most probably a thermodynamic-based correction of the values of the HSPs of small molecules could lead to a significant improvement of the predictive ability of the newly developed method. [ABSTRACT FROM AUTHOR]

Abstract Organic photodetectors were prepared based on polymer-fullerene blended heterojunctions using Poly[2-methoxy-5-(3′,7′-dimethyloctyloxy)-1,4-phenylenevinylene] (MDMO-PPV) and Phenyl-C 61 -Butyric-Acid-Methyl Ester (PCBM). In order to investigate and improve the sensitivity to short optical pulses, 5–10 micrometer thick layers were fabricated. A dual-solvent draw blade technique was developed to simplify the heterojunction production. The increased thickness resulted in a drastic reduction to the dark current. Both electrically inert nanoparticles and an evaporated fullerene interlayer were found to further improve the device performance. The external quantum efficiency was measured, as well as the fast pulse response in the limit of low photocarrier injection. Results showed a sensitivity to pulses of very small energy, 100 fJ, largely aided by a dark current that was below 10 nA/cm2. [ABSTRACT FROM AUTHOR]

We have developed a comprehensive numerical model for the transport and drying of solutions in thin porous media that consist of permeable fibers such as paper. We explicitly account for the gas-phase transport dynamics. Moreover, we introduce an empirical relation for the concentration- and molecular-weight dependence of the pore-fiber transport rate of the solutes. These two key elements enable us for the first time to realistically model two important phenomena relevant to inkjet printing technology. The first is the equivalent of the coffee-stain effect for dilute solutions in porous media. The second is the formation of solute rings for concentrated aqueous mixtures of compounds with a molecular weight significantly above that of water. Whereas the first is governed by spatially non-uniform solvent evaporation, the second case is dominated by solvent-mediated pore-fiber transport. We achieved a good qualitative agreement with the available experimental data. [Display omitted] [ABSTRACT FROM AUTHOR]

Water tolerance of ethanol-gasoline blends of various proportions is investigated using cosolvents such as TBA (tert-butyl alcohol), cyclohexane, heptane, acetone, iso-octane, and toluene at 300 K. Miscibility was studied using a simple experimental method for various proportions of water-ethanol gasoline blends with and without co-solvents. Results of water tolerance for each co-solvent are presented in this paper for stable mixture at room temperature.

Protein folding and assembly can be manipulated in in vitro systems by co-solvents at high concentrations. A number of co-solvents that enhance protein stability and assembly have been shown to be excluded from the protein surface. Such co-solvent exclusion has been demonstrated by dialysis experiments and shown to be correlated with their effects on protein stability and assembly. [ABSTRACT FROM AUTHOR]

This study reviewed and summarized the literature regarding the use of alcohols during hydrothermal liquefaction (HTL) of algal biomass feedstocks. The use of both pure alcohols and alcohol-water co-solvents were considered. Based upon this review, laboratory experiments were conducted to investigate the impacts of different alcohol co-solvents (ethanol, isopropanol, ethylene glycol, and glycerol) on the HTL treatment of a specific saltwater microalga (Tetraselmis sp.) at two temperatures: 300 °C and 350 °C. Based on their performance, two co-solvents, isopropanol and ethylene glycol, were selected to explore the effects of varying solvent concentrations and reaction temperatures on product yields and biocrude properties. The type and amount of added alcohol did not significantly affect the biocrude yield or composition. Biocrude yields were in the range of 30−35%, while a nearly constant yield of 21% insoluble products was observed, largely resulting from ash constituents within the algal feedstock. The benefits of using alcohol co-solvents (especially isopropanol) were the reduced viscosity of the biocrude products and reduced rates of viscosity increase with biocrude aging. These effects were attributed mainly to the physical properties of the co-solvent mixtures (solubility, polarity, density, etc.) rather than chemical processes. Under the reaction conditions used, there was no evidence that the co-solvents participated in biocrude production by means of hydrogen donation or other chemical processes. Recovery and recycling of the co-solvent present various challenges, depending upon the type and amount of the co-solvent that is used. For example, glycol solvents are recovered nearly completely within the aqueous product stream, whereas simple alcohols are partitioned between the biocrude and aqueous product streams. In commercial applications, the slight benefits provided by the use of co-solvents must be balanced by the challenges of co-solvent recovery and recycling.

New three-dimensionally-structured hybrid phospholipid vesicles, able to load clotrimazole in a high amount (10 mg/mL), were obtained for the first time in this work by significantly reducing the amount of water (≤10%), which was replaced with a mixture of glycerol and ethanol (≈90%). A pre-formulation study was carried out to evaluate the effect of both the composition of the hydrating medium and the concentration of the phospholipid on the physico-chemical properties of hybrid vesicles. Four different three-dimensionally-structured hybrid vesicles were selected as ideal systems for the topical application of clotrimazole. An extensive physico-chemical characterization performed using transmission electron microscopy (TEM), cryogenic transmission electron microscopy (cryo-TEM), 31P-NMR, and small-angle X-ray scattering (SAXS) displayed the formation of small, multi-, and unilamellar vesicles very close to each other, and was capable of forming a three-dimensional network, which stabilized the dispersion. Additionally, the dilution of the dispersion with water reduced the interactions between vesicles, leading to the formation of single unilamellar vesicles. The evaluation of the in vitro percutaneous delivery of clotrimazole showed an improved drug deposition in the skin strata provided by the three-dimensionally-structured vesicles with respect to the commercial cream (Canesten®) used as a reference. Hybrid vesicles were highly biocompatible and showed a significant antifungal activity in vitro, greater than the commercial cream Canesten®. The antimycotic efficacy of formulations was confirmed by the reduced proliferation of the yeast cells at the site of infection in vivo. In light of these results, clotrimazole-loaded, three-dimensionally-structured hybrid vesicles appear to be one of the most innovative and promising formulations for the treatment of candidiasis infections.

Efficiency of in-situ alkaline transesterification of dry biomass from a crop of Spirulina sp., using ultrasound-assisted and/or the addition of different co-solvents to the reaction medium was studied. The starting biomass had a total lipid content of 7.0% (Folch method), comprised mainly by the following fatty acids: 16:0 (44.2%), 18:3 (n–6) (23.3%), and 18: 2 (n–6) (11.1%). When the transesterification reaction was carried out without ultrasound, it only extracted 12.8% of lipids (0.9% of the biomass) after 2 h of reaction, achieving only a 63.6% ester content. When the process was carried out under the same conditions except for the ultrasound-assisted (80 W), the weight yield remained mostly unchanged, but the ester content increased to 97.6%. Additionally, when chloroform was added to methanol as a co-solvent in a 2:1 ratio it was possible to extract 43% of lipids. However, the ester content was reduced to 69.7%. Moreover, with maximum ultrasound power (180 W) a high ester content (96.9%) and a relatively high extraction yield (26%) were obtained, even without the co-solvent. These results show that the ultrasound significant increased the yield of the in-situ alkaline transesterification of Spirulina sp. biomass, promoting a higher percent recovery of lipids as well as ester content from the starting material. [ABSTRACT FROM AUTHOR]

The extraction of date sugar using supercritical extraction is a process that is still in its formative stages. In this study, a comprehensive parametric analysis of the supercritical fluid extraction (SFE) process using supercritical CO 2 with water/ethanol as co-solvents was performed to achieve maximum recovery of date sugar extract. The results showed that the maximum total sugar content (TSC) was 70.45 ± 0.01 g/100 g of DFP. This was made up of 7.42 g/100 g fructose, 6.49 g/100 g glucose, and 56.54 g/100 g sucrose. This was attained with 15 v/v% water as co-solvent, 50 ℃, and 200 bar. In addition, machine learning with non-linear regression and artificial neural network (ANN) ensembles was used for TSC prediction. The ANN results showed a strong correlation between operating parameters and sugar recovery with a total R2 of 0.986 ± 0.010. Compared to conventional hot water extraction method (CHWE), the CO 2 -SFE process resulted in a 1.4-fold increase in TSC recovery and a 2.1-fold increase in organic acids recovery. CO 2 -SFE demonstrated comparable TSC results with a difference of only 1.2% when compared to the ultrasound-assisted extraction ''USAE' method. The results of the detailed chemical analysis (HPLC and FT-IR) and morphological analysis (SEM) showed that the USAE and CO 2 -SFE were more efficient than CHWE. Supercritical extraction with co-solvents is particularly effective in recovering date sugar from date fruit, making it a desirable ingredient in a variety of food products. [Display omitted] • Supercritical CO 2 with co-solvent yielded 1.4-fold higher extraction than conventional method. • Neural network modeling of sugar extraction yielded an exceptional R2 of 0.995. • Proposed approach also extracted 2.1-fold more essential acids than conventional method. • Surface morphology analysis revealed the residue had a smooth surface without distortions. [ABSTRACT FROM AUTHOR]

This work investigates the antimicrobial activity of the Schinus molle L. leaves extracts obtained under supercritical conditions using carbon dioxide and co-solvents. Antimicrobial qualitative evaluation was carried out through the bioautography technique and the microorganisms studied were Staphylococcus aureus, Pseudomonas aeruginosas, Escherichia coli, Micrococcus luteus, and Salmonella choleraesuis. The supercritical fluid extraction was carried out in a pilot scale equipment using carbon dioxide modified by the addition of co-solvents, such as ethanol and water at 150 bar and 333 K. A mathematical modeling of the process was also performed.

Ferulic acid (FA) is a phenolic compound present in many natural extracts. To obtain high FA extraction yields using supercritical carbon dioxide (scCO 2 ), the extraction should be performed in the presence of co-solvents. This work reports FA solubility in scCO 2 /ethanol/water mixtures and its thermodynamic modelling using the Peng-Robinson equation of state. FA solubility in scCO 2 /ethanol was measured by a dynamic method at different temperatures (313, 323 and 333) K, pressures (20, 30 and 40) MPa and mole ratios of the scCO 2 /ethanol mixture (95:5 and 90:10). FA solubility in scCO 2 with ethanol and water was evaluated at 323 K and 30 MPa, at three different mole ratios of the scCO 2 /ethanol/water mixture (97.4:2:0.6, 93.5:5:1.5 and 88:9.3:2.7). Also measured was the solubility of FA in water and in ethanol at ambient pressure. By using 10% ethanol, the FA solubility in (scCO 2 + ethanol) attained values 120 times higher than FA solubility in pure scCO 2 and about 50 times lower than solubility in ethanol. The lowest value was obtained at 313 K and 20 MPa and the highest at 333 K and 40 MPa (1.9 × 10 −3 ); however, the co-solvent effect decreased when increasing pressure. Finally, the presence of the co-solvent is very important to obtain natural extracts rich in ferulic acid. The prediction of FA solubility in ternary and quaternary systems using the binary interaction parameters did not produce good results. Calculated values were smaller than the experimental values, probably due to the strong interactions between acid molecules and alcohol. [ABSTRACT FROM AUTHOR]

A second compound is generally associated with oligosaccharides as a strategy to maximize the solubilizing effect for nonpolar compounds. This study elucidated the role and the mechanism whereby liquid compounds interact in these supramolecular aggregates in the solubilization of triamcinolone. Three different oligosaccharides (beta-cyclodextrin, 2-hydroxipropil-beta-cyclodextrin, and randomly methylated beta-cyclodextrin) and two potent co-solvents (triethanolamine and N- methyl pyrrolidone) were carefully evaluated by using three distinct experimental approaches. Incredibly stable complexes were formed with cyclodextrins (CDs). The structure of the complexes was elucidated by magnetic resonance spectra 2D-ROESY. The interactions of the protons of ring “A” of the drug with H 3 and H 5 protons of the CD cavity observed in the binary complexes remained in both ternary complexes. Unlike the observed ternary associations with triethanolamine, N- methyl pyrrolidone competed with the triamcinolone CD cavity and considerably decreased the stability of the complex and the solubility of the drug. The molecular dynamics (MD) and quantum mechanics:molecular mechanics (QM:MM) calculations supported that triethanolamine stabilized the drug-CD interactions for the conformer identified in the 2D-ROESY experiments, improving the quality and uniformity of the formed complex. The role played by the co-solvent in the ternary complexes depends on its specific ability to interact with the CD cavity in the presence of the drug, which can be predicted in theoretical studies to select the best candidate. [ABSTRACT FROM AUTHOR]

Although the hydrothermal liquefaction is considered a promising technology for converting microalgae into liquid biofuels, there are still some disadvantages. This paper demonstrated that the bio-oil yield can be significantly improved by adding alcohols as co-solvents and carrying out the conversion at mild conditions (<250 °C), but at the expense of a reduced bio-oil quality. By adding ethanol, the bio-oil yields obtained (up to ∼60%) were comparable to the yield obtained at severe operating conditions using only water as solvent (54 ± 2% on average), but the quality of the bio-oil was lower. However, the main advantages of the process here described lie in the utilisation of wet microalgae (∼75% moisture) and alcohol concentrations which avoid both drying the microalgae and decreasing the amount of microalgae loaded in the reactor. [ABSTRACT FROM AUTHOR]

Herein, we report the detailed volumetric, compressibility and acoustical studies of carbohydrate-surfactant interactions in aqueous and mixed organic solvents at various temperatures. The interactions between sugars (ribose, glucose, sucrose and raffinose) and sodium dodecyl sulfate (SDS, an anionic surfactant) were studied in aqueous solutions at various temperatures, i.e. 293.15, 303.15 and 313.15 K using density and speed of sound measurements. Further, to clearly understand the sugar–surfactant interactions, various parameters such as molar volume ( V ϕ ), isentropic compressibility ( κ s ) and apparent molar isentropic compressibility ( κ ϕ , S ) were calculated from the obtained data. The observed results revealed that different saccharides exhibit pronounced effect on micellization of SDS which might be due to the differences in number of –OH linkages. The increase in such linkages results in dominance of sugar–water interactions, thus favoring the micelle formation. Further, to support such conclusion, viscosity measurements (relative viscosity and viscous relaxation time) of SDS in aqueous solutions of sugars were also examined. The effect of different co-solvents viz. dimethyl sulfoxide (DMSO), methanol (MeOH) and dioxane on sugar-surfactant interactions has also been discussed and demonstrated in this paper. [ABSTRACT FROM AUTHOR]

COSY proton nuclear magnetic resonance was used to measure the exchange rates of amide protons of hen egg white lysozyme (HEWL) in the pressure-assisted cold-denatured state and in the heat-denatured state. After dissolving lysozyme in deuterium oxide buffer, labile protons exchange for deuterons in such a way that exposed protons are substituted rapidly, whereas "protected" protons within structured parts of the protein are substituted slowly. The exchange rates k obs were determined for HEWL under heat treatment (80ºC) and under high pressure conditions at low temperature (3.75 kbar, -13ºC). Moreover, the influence of co-solvents (sorbitol, urea) on the exchange rate was examined under pressure-assisted cold denaturation conditions, and the corresponding protection factors, P, were determined. The exchange kinetics upon heat treatment was found to be a two-step process with initial slow exchange followed by a fast one, showing residual protection in the slow-exchange state and P-factors in the random-coil-like range for the final temperature-denatured state. Addition of sorbitol (500 mM) led to an increase of P-factors for the pressure-assisted cold denatured state, but not for the heat-denatured state. The presence of 2 M urea resulted in a drastic decrease of the P-factors of the pressure-assisted cold denatured state. For both types of co-solvents, the effect they exert appears to be cooperative, i.e., no particular regions within the protein can be identified with significantly diverse changes of P-factors.

Studies were carried out on solvent and supercritical extraction to obtain natural tannins. The results showed that the best co-solvent to extract tannin with CO2 supercritical was water with a concentration of 5.0% and the best trap rinse solvent was methanol.Neste trabalho foram utilizados dois processos de extração de tanino vegetal: extração a quente em aparelho Soxhlet e extração com CO2 supercítico. Os resultados mostraram que o melhor co-solvente para extração de taninos com CO2 supercrítico foi a água na concentração de 5% e o melhor solvente para lavagem do trap foi o metanol.

Effect of various organic co-solvents on catalytic activity and structural stability of three different Bacillus enzymes, including Bacillus licheniformis γ-glutamyltranspeptidase ( Bl GGT) and aldehyde dehydrogenase ( Bl ALDH), and Bacillus stearothermophilus aminopeptidase II ( Bs APII) were investigated. The experimental results revealed that almost all co-solvents had a detrimental effect on catalytic activity and molecular structure of enzymes at high concentrations. Acetonitrile and dimethylformamide caused a highest degree of enzyme inactivation; however, other more hydrophilic co-solvents, such as ethylene glycol and dimethyl sulfoxide, were better tolerated. High residual activity of Bl GGT was obtained in the majority of organic co-solvents tested, but catalytic activities of Bl ALDH and Bs APII were significantly decreased by the respective concentrations of the same co-solvents. Collectively, the favorable influence of these co-solvents on both catalytic activity and structural stability of Bl GGT makes this enzyme more suitable for biocatalytic applications. [ABSTRACT FROM AUTHOR]

Size exclusion chromatography is extensively used to separate proteins and to determine their apparent molecular weights. It separates proteins based on hydrodynamic volume, but interactions between the chromatography resin and proteins lead to non-size effects. This report discusses the impact of co-solvents [salt, urea, sodium dodecyl sulfate (SDS), dithiothreitol] in extraction media when separating wheat gluten proteins, soy glycinin, bovine serum albumin and ovalbumin on a Biosep-SEC-S4000 column. With acetonitrile/water (1:1, v/v) containing 0.05% (v/v) trifluoroacetic acid as eluent, salts and SDS in the extraction media increase while urea decreases non-size effects. Most gluten and globular proteins are extractable in sodium phosphate buffer (0.050 M; pH 6.8) containing 2.0% (w/v) SDS. This chromatographic medium allows analyzing mixtures of various proteins without any non-size effects. [ABSTRACT FROM AUTHOR]

The aim of the present work was to investigate the potential of the new and innovative artificial barrier, Permeapad™, when exposed to surfactants and co-solvents, often employed for poorly water soluble compounds. The barrier was in addition also exposed to fasted and fed state simulated intestinal fluids versions 1 and 2 (FaSSIF and FeSSIF), all of which the Permeapad™ barrier was compatible with based upon relative comparison of the permeability of the hydrophilic marker calcein in phosphate buffer. The new barrier therefore holds a huge potential due to its functional stability and robustness. It can be used as a standard tool to investigate permeability of drugs in the presence of different surfactants and co-solvents, from DMSO stock solutions at even high concentrations and for the evaluation of permeability in the presence of biomimetic media (BMM). 1 1 Biomimetic media = BMM. [ABSTRACT FROM AUTHOR]

Self-micro emulsifying drug delivery system (SMEDDS) is one of the methods to improve solubility and bioavailability of poorly soluble drug(s). The knowledge of the solubility of pharmaceuticals in pure lipidic solvents and solvent mixtures is crucial for designing the SMEDDS of poorly soluble drug substances. Since, experiments are very time consuming, a model, which allows for solubility predictions in solvent mixtures based on less experimental data is desirable for efficiency. Solvents employed were Labrafil® M1944CS and Labrasol® as lipidic solvents; Capryol-90®, Capryol-PGMC® and Tween®-80 as surfactants; Transcutol® and PEG-400 as co-solvents. Solubilities of both drugs were determined in single solvent systems at temperature ( T ) range of 283–333 K. In present study, we investigated the applicability of the thermodynamic model to understand the solubility behavior of drugs in the lipiodic solvents. By using the Van’t Hoff and general solubility theory, the thermodynamic functions like Gibbs free energy, enthalpy and entropy of solution, mixing and solvation for drug in single and mixed solvents were understood. The thermodynamic parameters were understood in the framework of drug–solvent interaction based on their chemical similarity and dissimilarity. Clotrimazole and Fluconazole were used as active ingredients whose solubility was measured in single solvent as a function of temperature and the data obtained were used to derive mathematical models which can predict solubility in multi-component solvent mixtures. Model dependent parameters for each drug were calculated at each temperature. The experimental solubility data of solute in mixed solvent system were measured experimentally and further correlated with the calculates values obtained from exponent model and log-linear model of Yalkowsky. The good correlation was observed between experimental solubility and predicted solubility. [ABSTRACT FROM AUTHOR]