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Here, we propose an optimised protocol for controlling the initial water activity (aw) in organic reaction mixtures with soluble lipase to ensure reproducible and consistent enzyme activity measurements. Pre‐equilibration above saturated salt solutions was used to set aw of the reaction media, where aw was tracked with a hygrometer. Consistent stirring of the suspension and volume correction to compensate for solvent evaporation were found to be critical. The protocol was tested on Candida antarctica lipase B (CALB) in soluble and immobilised forms in three organic solvents (acetonitrile, methyl tert‐butyl ether, and hexane) at four different water activities ranging from 0.12 to 0.97. Soluble and immobilised CALB had similar aw‐profiles and showed the highest enzyme activity in hexane. The optimised protocol expands the possibility to study enzyme kinetics from immobilised enzymes to soluble enzymes. [ABSTRACT FROM AUTHOR]

In this review, the effect of organic solvents on microalgae cultures from molecular to industrial scale is presented. Traditional organic solvents and solvents of new generation-ionic liquids (ILs), are considered. Alterations in microalgal cell metabolism and synthesis of target products (pigments, proteins, lipids), as a result of exposure to organic solvents, are summarized. Applications of organic solvents as a carbon source for microalgal growth and production of target molecules are discussed. Possible implementation of various industrial effluents containing organic solvents into microalgal cultivation media, is evaluated. The effect of organic solvents on extraction of target compounds from microalgae is also considered. Techniques for lipid and carotenoid extraction from viable microalgal biomass (milking methods) and dead microalgal biomass (classical methods) are depicted. Moreover, the economic survey of lipid and carotenoid extraction from microalgae biomass, by means of different techniques and solvents, is conducted. [ABSTRACT FROM AUTHOR]

The mole fraction solubility of paclobutrazol ((R,R) and (S,S)) mixture in nine pure solvents including ethanol, isopropanol, n -propanol, 1-butanol, ethyl acetate, toluene, acetone, acetonitrile and 1,4-dioxane was determined experimentally by using the isothermal saturation method over a temperature range from (278.15 to 318.15) K under atmospheric pressure. The mole fraction solubility of paclobutrazol in the selected solvents increased with a rise of temperature. In general, at a certain temperature, they decreased according to the following order in different solvents except for ethyl acetate: toluene > 1,4-dioxane > acetone > 1-butanol > n -propanol > ethanol > isopropanol > acetonitrile. The paclobutrazol solubility showed stronger dependency on temperature in ethyl acetate than in the other solvents. The solubility determined for paclobutrazol in the selected solvents was correlated with the modified Apelblat equation, λh equation, Wilson model and NRTL model. The maximum values of root-mean-square deviation ( RMSD ) and relative average deviation ( RAD ) were 3.98 × 10 −4 and 1.53%, respectively. On the whole, the four thermodynamic models were all acceptable for describing the systems of paclobutrazol in these solvents. Furthermore, the mixing Gibbs energy, mixing enthalpy, mixing entropy, activity coefficient at infinitesimal concentration ( γ 1 ∞ ) and reduced excess enthalpy ( H 1 E, ∞ ) were obtained. The mixing process of paclobutrazol was spontaneous and exothermic in the solvents studied. The solubility determined and the thermodynamic properties derived should be very helpful for optimizing the purification process of paclobutrazol. [ABSTRACT FROM AUTHOR]

This work presents a straightforward methodology to achieve small linear trinuclear molecules based on the CoII-carboranylcarboxylate system obtained by carving a 1D polynuclear analogous system with the use of diethylether. The reaction of the carboranylcarboxylic ligand, 1-CH3-2-CO2H-1,2-closo-C2B10H10 (LH) with different cobalt salts leads to the polynuclear compound [Co2(μ-H2O)(1-CH3-2-CO2-1,2-closo-C2B10H10)4(THF)4], 1 and the polymeric [Co(μ-H2O)(1-CH3-2-CO2-1,2-closo-C2B10H10)2]n(H2O)n2. This latter 1D chain has been obtained by an unprecedented synthetic strategy for the isolation of cobalt(ii) compounds. [Co3(μ-H2O)2(1-CH3-2-CO2-1,2-closo-C2B10H10)6(H2O)2(C4H10O)2], 3 is formed by the dissociation of the polymeric structure that forms 2 when a mild coordinating solvent such as diethylether is added. These compounds have been characterized by analytical and spectroscopic techniques. X-ray analysis of 1 and 3 revealed that 1 presents a dinuclear structure whereas 3 is trinuclear; in both cases a six-coordinated CoII compound with water molecules bridging each of the two CoII centres has been observed. The magnetic properties of 1 and 3 show a weak antiferromagnetic behaviour, respectively, between the CoII centres mediated by two carboxylate ligands and a molecule of water. [ABSTRACT FROM AUTHOR]

Periodic patterns resembling spiralswere observed to form spontaneouslyupon unassisted cooling of d-glucaric acid- and d-galactaric acid–based polyamide solutions in N-methyl-N-morpholine oxide (NMMO) monohydrate. Similarobservations were made in d-galactaric acid-based polyamide/ionicliquid (IL) solutions. The morphologies were investigated by optical,polarized light and confocal microscopy assays to reveal pattern details.Differential scanning calorimetry was used to monitor solution thermalbehavior. Small- and wide-angle X-ray scattering data reflected thecomplex and heterogeneous nature of the self-organized patterns. Factorssuch as concentration and temperature were found to influence spiraldimensions and geometry. The distance between rings followed a first-orderexponential decay as a function of polymer concentration. Fourier-TransformInfrared Microspectroscopy analysis of spirals pointed to H-bondingbetween the solvent and the pendant hydroxyl groups of the glucoseunits from the polymer backbone. Tests on self-organization into spiralsof ketal-protected d-galactaric acid polyamides in NMMO monohydrateconfirmed the importance of the monosaccharide’s pendant freehydroxyl groups on the formation of these patterns. Rheology performedon d-galactaric-based polyamides at high concentration inNMMO monohydrate solution revealed the optimum conditions necessaryto process these materials as fibers by spinning. The self-organizationof these sugar-based polyamides mimics certain biological materials. [ABSTRACT FROM AUTHOR]

Highlights • Errors are found in model coefficients for mathematical representations. • NRTL model coefficients fail to back-calculated observed solubility. • Coefficients of NRTL model were re-analyzed. Abstract Errors were discovered regarding the published equation coefficients of Yao and co-workers (2017) for mathematically describing the solubility of 3,5-dimethylpyrazole in nine organic solvents using the NRTL model. Larger differences were found between our back-calculated data and those reported in the authors' published paper. The equation parameters were re-regressed based on the reported solubility data. [ABSTRACT FROM AUTHOR]

The solubility of N -phenylanthranilic acid in nine pure organic solvents including methanol, ethanol, acetone, acetonitrile, ethyl acetate, n -propanol, isopropanol, 1-butanol and toluene was determined experimentally by using the isothermal saturation method within the temperature range from (283.15 to 318.15) K under atmosphere pressure. For all the selected solvents, the solubility increased with a rise in temperature. In general, solubility followed the order from high to low in different solvents: acetone > ethyl acetate > 1-butanol > n -propanol > ethanol > isopropanol > methanol > toluene > acetonitrile. The experimental solubility values for N -phenylanthranilic acid in these solvents was correlated by the modified Apelblat equation, λh equation, Wilson model and NRTL model. The largest value of root-mean-square deviation ( RMSD ) was 8.94 × 10 −4 , and of relative average deviation ( RAD ), 3.55%. For a specific solvent, the RAD value obtained with the modified Apelblat equation was smaller than those with the other models. By and large, the four thermodynamic models were all acceptable for the systems of N -phenylanthranilic acid in these solvents. In addition, the mixing properties of the solutions, including the mixing Gibbs energy, mixing enthalpy, mixing entropy, activity coefficient at infinitesimal concentration ( γ 1 ∞ ) and reduced excess enthalpy ( H 1 E, ∞ ) were achieved. The solution process of N -phenylanthranilic acid was spontaneous and endothermic in the studied solvents. The solubility and modelling and thermodynamic studies would be helpful for the purification process of N -phenylanthranilic acid. [ABSTRACT FROM AUTHOR]

The solubility of 2,4-dihydro-5-methyl-2-(4-methylphenyl)-3H-pyrazol-3-one in twelve organic solvents including methanol, ethanol, n -propanol, isopropanol, ethylbenzene, toluene, n -butanol, acetonitrile, ethyl acetate, 1,4-dioxane, cyclohexane and isopentanol were determined experimentally by using the isothermal saturation method over a temperature range from (278.15 to 313.15) K under 101.3 kPa. For the temperature range studied, the solubility of 2,4-dihydro-5-methyl-2-(4-methylphenyl)-3H-pyrazol-3-one in the solvents increased with a rise of temperature. The mole fraction solubility obeyed the following order from high to low in different solvents: isopentanol > 1,4-dioxane > n -butanol > n -propanol > ethyl acetate > methanol > ethanol > isopropanol > ethylbenzene > toluene > acetonitrile > cyclohexane. The obtained solubility data of 2,4-dihydro-5-methyl-2-(4-methylphenyl)-3H-pyrazol-3-one in the studied solvents were correlated with the modified Apelblat equation, λh equation, Wilson model and NRTL model. The largest values of root-mean-square deviation ( RMSD ) and relative average deviation ( RAD ) were 1.35 × 10 −4 and 0.32%, respectively. The RAD values obtained with the modified Apelblat equation were smaller than those with the other three models for a given solvent. So the four thermodynamic models were all acceptable for the systems of 2,4-dihydro-5-methyl-2-(4-methylphenyl)-3H-pyrazol-3-one in these solvents. Furthermore, the mixing Gibbs energy, mixing enthalpy, mixing entropy, activity coefficient ( γ 1 ∞ ) and reduced excess enthalpy ( H 1 E, ∞ ) at infinitesimal concentration were calculated. The obtained solubility and thermodynamic studies would be very helpful for optimizing the purification process of 2,4-dihydro-5-methyl-2-(4-methylphenyl)-3H-pyrazol-3-one. [ABSTRACT FROM AUTHOR]

A simple dual impedance tester has been designed for determining the water content in organic solvents. The detection cells are formed by a pair of semi-cylindrical electrodes of aluminium foil, located opposite one another around the outer surface of a glass tube with the tested solution. Thus, the electrodes are not in contact with the analysed solution. The detection cells are connected as a capacity determining the frequency of the integrated multivibrator. The analytical signal is the difference between the frequency of the multivibrator with the measuring cell filled with the analysed solution and the multivibrator with the cell filled with pure anhydrous solvent. Solvents with various permittivities and water contents to 50% v/v were tested, with a detection limit from 0.2% (dioxane) to 1.4% (acetonitrile). The method can also be used for determining the relative permittivity of solvents with various water contents. The detector can even be used outside the laboratory because it can be powered by a standard 9-V battery. [ABSTRACT FROM AUTHOR]

Knowledge of solubility for terephthaldialdehyde in different solvents is essential for its purification and further theoretical investigations. In this work, the solubility of terephthaldialdehyde in ten solvents of ethanol, n -propanol, 1-butanol, isopropanol, benzyl alcohol, 2-butanone, acetonitrile, isopentanol, N , N -dimethylformamide, and acetone were determined by an isothermal saturation method at temperatures ranging from (273.15 to 318.15) K under atmospheric pressure. By and large, the solubility of terephthaldialdehyde decrease according to the following order in different solvents: N , N -dimethylformamide > benzyl alcohol > 2-butanone > acetone > acetonitrile > isopentanol > 1-butanol > n -propanol > ethanol > isopropanol. In addition, values of the measured solubility were correlated with the Buchowski–Książczak λh equation, modified Apelblat equation, Wilson model and NRTL model. The largest values of relative average deviation and root-mean-square deviation were 1.2% and 8.7 × 10 −4 , respectively. The correlated values with the four models agreed well with the experimental values and the Apelblat equation model provided better correlation results than the other three models. Furthermore, the mixing properties, including mixing Gibbs energy, mixing enthalpy, mixing entropy, activity coefficient at infinitesimal concentration ( γ 1 ∞ ) and reduced excess enthalpy ( H 1 E, ∞ ) were computed. The solution process of terephthaldialdehyde was spontaneous and favourable in these solvents. Knowledge of the solubility and thermodynamic investigations would be very important for optimizing the purification process of terephthaldialdehyde. [ABSTRACT FROM AUTHOR]

In this study, we prepared highly porous polyamide (PA) monolith in a continuous and scalable solution foaming process. The created materials, displaying a structure with both open and closed pores, had oils or organic solvents uptake capacities ranging from about 4.8 to 10.7 g/g. Moreover, they had sorption retention higher than 96% after 10 cycling tests because the structures of pores were not broken during the adsorption process. On the other hand, they absorbed oils and organic solvents rapidly and reached saturation in 30 s. A great promising way was provided to fabricate highly porous PA for the cleanup of large-scale oil or organic solvent spills. [ABSTRACT FROM AUTHOR]

Solubilities of 3-methyl-4-nitrobenzoic acid in twelve organic solvents of ethanol, isopropanol, n -propanol, n -butanol, methanol, ethyl acetate, toluene, acetone, acetonitrile, 1,4-dioxane, N -methyl-2-pyrrolidone and N , N -dimethylformamide were determined experimentally by using the isothermal saturation method over a temperature range from (283.15–318.15) K under 101.1 kPa. The solubilities of 3-methyl-4-nitrobenzoic acid in each solvent increased with the increase in temperature. In general, the solubility obeyed the following order from high to low in different solvents: ( N , N -dimethylformamide, N -methyl-2-pyrrolidone) > 1,4-dioxane > acetone > toluene > ethyl acetate > isopropanol > (methanol, ethanol, n -propanol, n -butanol) > acetonitrile. The experimental solubility data of 3-methyl-4-nitrobenzoic acid in the selected solvents were correlated by the modified Apelblat equation, λh equation, Wilson model and NRTL model. The maximum values of root-mean-square deviation ( RMSD ) and relative average deviation ( RAD ) were 13.69 × 10 −4 and 1.18%, respectively. Generally, the four thermodynamic models were all acceptable for the systems of 3-methyl-4-nitrobenzoic acid in these solvents. In addition, the mixing Gibbs energy, mixing enthalpy, mixing entropy, activity coefficient at infinitesimal concentration ( γ 1 ∞ ) and reduced excess enthalpy ( H 1 E, ∞ ) were calculated. The dissolution process of 3-methyl-4-nitrobenzoic acid in the solvents was spontaneous and endothermic. The obtained solubility and thermodynamic studies would be very helpful for optimizing the purification process of 3-methyl-4-nitrobenzoic acid. [ABSTRACT FROM AUTHOR]

Lipoquinones are the topic of this review and are a class of hydrophobic lipid molecules with key biological functions that are linked to their structure, properties, and location within a biological membrane. Ubiquinones, plastoquinones, and menaquinones vary regarding their quinone headgroup, isoprenoid sidechain, properties, and biological functions, including the shuttling of electrons between membrane-bound protein complexes within the electron transport chain. Lipoquinones are highly hydrophobic molecules that are soluble in organic solvents and insoluble in aqueous solution, causing obstacles in water-based assays that measure their chemical properties, enzyme activities and effects on cell growth. Little is known about the location and ultimately movement of lipoquinones in the membrane, and these properties are topics described in this review. Computational studies are particularly abundant in the recent years in this area, and there is far less experimental evidence to verify the often conflicting interpretations and conclusions that result from computational studies of very different membrane model systems. Some recent experimental studies have described using truncated lipoquinone derivatives, such as ubiquinone-2 (UQ-2) and menaquinone-2 (MK-2), to investigate their conformation, their location in the membrane, and their biological function. Truncated lipoquinone derivatives are soluble in water-based assays, and hence can serve as excellent analogs for study even though they are more mobile in the membrane than the longer chain counterparts. In this review, we will discuss the properties, location in the membrane, and syntheses of three main classes of lipoquinones including truncated derivatives. Our goal is to highlight the importance of bridging the gap between experimental and computational methods and to incorporate properties-focused considerations when proposing future studies relating to the function of lipoquinones in membranes. [ABSTRACT FROM AUTHOR]

The lack of an eco-friendly approach towards application of polyaniline as a coating material has been one of the most challenging tasks. Herein, the synthesis of green Prunus domestica gum grafted polyaniline (PDG-g-PANI) composite is reported by a cost-effective emulsion polymerization for application as an efficient anti-corrosion material for mild steel (MS) and stainless steel (SS) in a strong corroding environment. The composite formation was confirmed by Ultraviolet Visible (UV-Visible) and Fourier Transformed Infrared (FTIR) spectroscopies. X-ray diffraction data revealed the amorphous nature of the PDG-g-PANI. Scanning Electron Microscopic (SEM) images showed a bi-layered structure having a parent porous layer of PANI coated with afibrous layer of PDG. The solubility test confirmed the dissolution of PDG-g-PANI in common organic solvents such as acetone, ethanol, propanol, butanol, chloroform, N-Methyl-2-pyrrolidone, dimethyl sulfoxide, and the mixture of propanol and chloroform. The polarization curve, open circuit potential, electrochemical impendence spectroscopy (EIS), and gravimetric analysis were applied to investigate the corrosion protection behavior of the composite on MS and SS in 3.5% NaCl and 1 M H2SO4 solution. The PDG-g-PANI-coated MS exhibited 96% corrosion inhibition efficiency as compared to 86% and 43% for pristine PANI and PDG in 3.5% NaCl solution while PDG-g-PANI-coated SS showed 98% corrosion inhibition efficiency. Moreover, 99% and 96.6% corrosion protection was observed for PDG-g-PANI-coated MS and SS in 1 M H2SO4 solution. Gravimetric studies revealed that PDG-g-PANI coating can protect MS up to 93% for 14 days in salt solution while 97% corrosion inhibition efficiency was retained for 2 months in open air. [ABSTRACT FROM AUTHOR]

Abraham model solute descriptors are calculated for 5-nitro-8-hydroxyquinoline, 2-methyl-6-nitroaniline, and terephthaldialdehyde using experimental solubility data taken from papers published in This Journal in 2016. The calculated solute descriptors are then used to predict the solubility of the three fore-mentioned solutes in 29 different organic solvents of varying polarity and hydrogen-bonding character. [ABSTRACT FROM AUTHOR]

The influence of water-ethanol (HO-EtOH), water-acetone (HO-MeAc) and waterdimethylsulfoxide (HO-DMSO) solvents on the reaction of the molecular complex formation between ether 18-crown-6 (18C6) and small peptide glycyl-glycyl-glycine (3Gly) has been studied at T = 298.15 K. The thermodynamic parameters for the reaction (log K, Δ G, Δ H, Δ S) were obtained from calorimetric titration experiments carried out by means of the calorimetric system TAM III (TA Instruments, USA). The thermodynamics of the [3Gly18C6] molecular complex formation is discussed in comparison with thermodynamic parameters of complex formation between 18C6 and amino acids in mixed solvents using the sоlvation-thermodynamic approach. [ABSTRACT FROM AUTHOR]

The addition of organic solvents, such as ethanol, to molecules in solution is an effective process for crystallization and is used in industrial settings (i.e. pharmaceutical production, downstream processing, etc.). In this study, we use solubility data of all proteinogenic α-amino acids in binary ethanol/water systems to model their excess solubility. We use the empirical and regressive models of Gude and NRTL and the predictive Jouyban-Acree model. Based on the results, we hypothesize that amino acids that are spherical and lack a reactive side chain show little or no excess solubility. Being rod-like and/or having a reactive side chain leads to a positive excess solubility in a mixed solvent of ethanol and water. The empirical and regressed models, NRTL and Gude, fit the data well and the predictive Jouyban-Acree model, not originally intended to be used for small molecules, is less accurate but offers insights into the thermodynamic properties of the amino acids. [ABSTRACT FROM AUTHOR]

With the isothermal dissolution equilibrium method, the solid-liquid phase equilibrium for 5-amino-3-methyl-1-phenylpyrazole in ten organic solvents including methanol, ethanol, n -propanol, isopropanol, 2-butanone, acetonitrile, n -butanol, toluene, 1,4-dioxane and isobutanol was established over a temperature range from (283.15 to 318.15) K at atmospheric pressure (101.1 kPa), and the solubility of 5-amino-3-methyl-1-phenylpyrazole in these solvents were determined by a high-performance liquid chromatography (HPLC). The mole fraction solubility of 5-amino-3-methyl-1-phenylpyrazole in the solvents increased with increasing temperature within the temperature range studied, and obeyed the following sequence from high to low in different solvents: 1,4-dioxane > acetonitrile > methanol > isobutanol > ethanol > n -propanol > isopropanol > 2-butanone > toluene > cyclohexane. The obtained solubility values of 5-amino-3-methyl-1-phenylpyrazole were correlated with the modified Apelblat equation, λh equation, Wilson model and NRTL model. The maximum values of root-mean-square deviation ( RMSD ) and relative average deviation ( RAD ) were 4.95 × 10 − 4 and 0.62%, respectively. In total, the four thermodynamic models were all acceptable for describing the solubility behavior of 5-amino-3-methyl-1-phenylpyrazole in these solvents. Furthermore, the mixing Gibbs energy, mixing enthalpy, mixing entropy, activity coefficient at infinitesimal concentration and reduced excess enthalpy were obtained with Wilson model. The results demonstrated that the dissolution process of 5-amino-3-methyl-1-phenylpyrazole was spontaneous and favorable in the ten organic solvents. Moreover, the solute–solvent intermolecular interaction was roughly estimated based on the values of activity coefficients. The determined solubility data and thermodynamic models in this work would be helpful to optimize the purification procedure of 5-amino-3-methyl-1-phenylpyrazole. [ABSTRACT FROM AUTHOR]

The partition coefficients, Kmim, of N-methylimidazole (mim) in two-component systems composed of ionic liquid (IL) and a series of organic solvents immiscible with ILs (butyl acetate, ethyl acetate, tert-butyl methyl ether, diethyl ether and cyclohexane) were determined by a shake-flask method. The influence of different factors such as temperature, solvent polarity, mim concentration, and water content on Kmim by using 1-butyl-3-methylimidazolium chloride {[C4C1im]Cl} as a model compound was comprehensively studied. The calculated thermodynamic functions of transfer (ΔtrG0Δ, ΔtrH0, ΔtrS0) showed that the mim migration (IL→organic phase) is a thermodynamically unfavorable and enthalpy-determined process in the temperature range of 298.15 to 328.15K; however, the results suggested that mim partition toward the organic phase can be enhanced by the rational manipulation of the extraction conditions. Experiments conducted with other 1-alkyl-3-methylimidazolim chlorides (CnC1im]Cl (n = 6, 8, 10) revealed that mim possesses similar behavior and can be successfully washed out from the ILs by extraction with organic solvents. The results obtained in this study give some clues toward the choice of an appropriate solvent and conditions to be employed for the purification of halide-based ILs by means of a liquid-liquid extraction. [ABSTRACT FROM AUTHOR]

Chitin is an abundant natural nitrogen-containing biopolymer with great application potential in materials, environment, energy, and health. However, the structure characteristics and processing technologies have required intense research in related applications. In particular, there have been great efforts to developing solvents for chitin, and the results so far are quite encouraging. This review summarizes the main solvent systems used for chitin, namely the aqueous solvent systems (mineral acids, inorganic salt aqueous solutions, alkali aqueous solutions) and non-aqueous ones (LiCl-dimethylacetamide solvents, CaCl2·2H2O saturated methanol, ionic liquids, deep eutectic solvents, and protic organic solvents). The solvent properties, dissolution methods, and solution properties are discussed in detail. Special attention is paid to the dissolution mechanism in each system. This review can provide a reference for understanding the dissolution behavior of chitin and finding suitable solvents for it. [ABSTRACT FROM AUTHOR]

Cellulose acetate-tin(IV) molybdophosphate (CATMP) composite exchanger was prepared by mixing biopolymer celluloseacetate with its inorganic counterpart tin(IV) molybdophosphate (TMP) using sol-gel method. The physical characterization of the as synthesized exchanger was carried out by FTIR, XRD, BET, TGA-DTG and SEM-EDX techniques. Chemical properties such as ion exchange capacity, chemical stability, pH and distribution behavior were carried out. The average IEC of the composite material, as determined by batch equilibrium, was found to be 2.43 meq/g for Na+ ion; higher than its inorganic counterpart, i.e. 1.41 meq/g. This exchanger was also found to be stable in water, acids and organic solvents, but unstable in basic medium. The distribution study (Kd) of the exchanger in different solvent systems showed promising separation potential of the exchanger towards metal ions of analytical interest from a given mixture of toxic heavy metal ions. The sorption studies revealed that the material was selective for Cr(III) and Cd(II) ions and moderately selective for Co(II) ion in solvents employed in this work. Its selectivity was examined by achieving some important binary separations of metal cations on its column indicating its promising application in environmental pollution abatement. [ABSTRACT FROM AUTHOR]

The solubility behavior and solution chemistry of CL-20/MTNP (2,4,6,8,10,12-hexanitro-hexaaza-isowurtzitane/1-methyl-3,4,5-trinitropyrazole) energetic cocrystals in organic solvents were first investigated to offer some important information on thermodynamics. The phase solubility diagram (PSD) and eutectic point (Keu1) of three solvents were also determined. Moreover, the solubility behavior of CL-20/MTNP energetic cocrystals was explained using the solubility product and solution complexation theories. The solution complexation results indicated that the CL-20/MTNP cocrystal has the strongest complexation effect in ethanol. The Keu1 values were all below 1 in three studied solvents, suggesting that the CL-20/MTNP cocrystal was less soluble than the other two pure components. Furthermore, studying the solubility behavior and solution chemistry of the CL-20/MTNP cocrystals has provided further insights into the screening, preparation and scaling-up of energetic cocrystals. [ABSTRACT FROM AUTHOR]

Common separation materials are divided into two-dimensional (2D) materials and three-dimensional (3D) materials, among which three-dimensional materials have excellent durability and stability. Herein, we developed a durable S@P@PU sponge by simply immersing polyurethane (PU) sponges in a blending solution of starch granules and polydimethylsiloxane (PDMS). Blending starch granules and PDMS could achieve more reliable adhesion of starch granules to the PU sponge by utilizing the high adhesion of PDMS. At the same time, the presence of starch granules could make PDMS form a spot-like secondary structure on the sponge. The sponge exhibited excellent hydrophobicity and high organic solvent affinity, and could separate and absorb organic solvents from the turbulent flow. The results showed that the sponge could absorb and hold 46 times its organic solvent weight, with a separation efficiency greater than 98.5% for different organic solvents. In addition, the sponge maintained a water contact angle of more than 140° after 40 abrasion cycles or after immersion in different pH and salt solutions for 48 h, showing excellent mechanical durability and chemical stability. [Display omitted] • The modified sponge water contact angle is increased from 86° to 157°. • In extreme environments, sponges still have water contact angles of >140°. • The separation efficiency of the modified sponge is greater than 99%. • The modified sponge can hold 46 times its own weight of organic solvent. • The sponge has the advantages of low cost and short time consumption. [ABSTRACT FROM AUTHOR]

The development of a novel film fabrication strategy, named demulsification‐induced fast solidification (DIFS), for the rapid fabrication of large‐area polymer films is reported in this study. The polymer films are fabricated through dialysis and dipping processes using emulsions and a demulsifier based on the DIFS method. Furthermore, robust and flexible free‐standing films with controllable thicknesses and functionalities, such as tunable mechanical properties (elongation at break of 350–980% and ultimate tensile strength of 0.21–1.88 MPa); excellent optical properties (optical transmittance greater than 52.03% in the visible region, refractive index of 1.4888 ± 0.0001, and Abbe number of 52.1 ± 1.1); and luminescence properties, are rapidly and easily prepared by mechanical exfoliation based on the DIFS method. The results show that this academic concept and fabrication method will provide support for the design and preparation of functional polymer films that are highly desirable for optical, flexible device, and wearable material applications. [ABSTRACT FROM AUTHOR]

The total petroleum hydrocarbon (TPH) extraction potential of organic solvents including dichloromethane (DCM), pentane, hexane, methanol, ethanol, propanol, and acetone was investigated along with the effect of water content in solvents for their efficiency of extraction. The extent of TPH extraction was analyzed using various extraction schemes (i.e., solvent/solid ratio, treatment time, extraction method, solvent/water ratio) to better understand the physical and chemical factors controlling TPH release from contaminated soils. More TPH was extracted with increasing solvent/solid ratio and increasing time. The extent of TPH extracted also varied depending on the extraction method, solvent type, and solvent/water ratio, but was highest when using the total extraction method and 100% DCM. However, the efficiency of TPH extraction decreased dramatically with the increase in the water content in organic solvents. The results also showed that TPH extraction using DCM was the best option for achieving cost-effective, eco-friendly outcomes along with remediation goals. DCM used in solvent extraction to remediate diesel-contaminated soils showed low toxicity, low cost, high recycling potential, and high efficiency compared to the other solvents tested in this study. [ABSTRACT FROM AUTHOR]

Review: 183 refs. [ABSTRACT FROM AUTHOR]

A simplification of the overall method of producing trimethylsilylcellulose solutions in common organic volatile solvents is reported. Microcrystalline cellulose was derivatized aiming its solubilization in tetrahydrofuran and toluene to obtain ultra-thin films of cellulose by spin-coating. The main simplifications are: 1) elimination of a swelling step before dissolution in the binary solvent N,N -dimethylacetamide/LiCl by using microcrystalline cellulose; 2) derivatization of cellulose –OH groups with –Si(CH 3 ) 3 groups was successful with no additional catalyst, like trimethylsilyl chloride, the degree of substitution (DS) being 2.2 ± 0.1. The DS at the extreme surface of the films was computed from the X-ray Photoelectron Spectroscopy data: using solely C 1s fitted component areas and, alternatively, from both C 1s and Si 2p areas. The DS estimated with a technique specific of the surface is close to the bulky one obtained from gravimetric measurements reported in the literature for materials synthesized with catalyst. The topographic uniformity is shown by Atomic Force Microscopy. [ABSTRACT FROM AUTHOR]

The influence of the polar, aprotic solvent propylene carbonate on the interfacial structure of the ionic liquid (IL) 1-butyl-1-methylpyrrolidinium tris(pentafluoroethyl)trifluorophosphate on sapphire was investigated by high-energy x-ray reflectivity. Experiments at solvent concentrations between 17 mol.% and 83 mol.% bridge the gap between diluted electrolytes described by the classical Gouy- Chapman theory and pure ionic liquids. Analysis of our experimental data revealed interfacial profiles comprised of alternating anion and cation enriched regions decaying gradually into the bulk liquid. With increasing solvent concentration, we observed a decrease in correlation length of the interfacial layering structure. At high ion concentrations, solvent molecules were found to accumulate laterally within the layers. By separating like-charged ions, they reduce their Coulomb repulsion. The results are compared with the bulk structure of IL/solvent blends probed by x-ray scattering and predictions from fundamental fluid theory. [ABSTRACT FROM AUTHOR]

Optimizing synthesis factors of polyamide top layers is an important requirement in the design of thin film composite (TFC) membranes. In this research, the top layer fabrication method (conventional, heat curing, and spin coating), type of acid acceptor (sodium carbonate, sodium hydroxide, and triethylamine), type of organic phase solvent (hexane, heptane, and mixed hexane/heptane), and concentration of surfactant sodium dodecyl sulfate (0, 0.5, and 1 wt %) are selected as the control parameters of this synthesis and optimized using the Taguchi approach. The analysis of variance shows that the layer fabrication method is the most influential parameter on water flux and salt (NaCl) rejection of TFCs. Furthermore, although the type of organic solvent has not a significant contribution to the water flux, it is another significant factor affecting the rejection. The optimized membrane is then used to construct structure–property relationships and to understand the influence of each individual factor on the desalination performance. Accordingly, a TFC membrane with the top layer fabricated by the heat curing method, in the presence of Na2CO3 as the acid acceptor, hexane as the organic phase solvent and 0.5 wt % of the surfactant is prepared that shows water permeance of 2.73 L m−2 h−1 bar−1 and NaCl rejection of 98.1%. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020, 137, 48858. [ABSTRACT FROM AUTHOR]

The exceptional solution processing potential of graphene oxide (GO) is always one of its main advantages over graphene in terms of its industrial relevance in coatings, electronics, and energy storage. However, the presence of a variety of functional groups on the basal plane and edges of GO makes understanding suspension behavior in aqueous and organic solvents, a major challenge. Acoustic spectroscopy can also measure zeta potential to provide unique insight into flocculating, meta-stable, and stable suspensions of GO in deionized water and a variety of organic solvents (including ethanol, ethylene glycol, and mineral oil). As expected, a match between solvent polarity and the polar functional groups on the GO surface favors stable colloidal suspensions accompanied by a smaller aggregate size tending toward disperse individual flakes of GO. This work is significant since it describes the characteristics of GO in solution and its ability to act as a precursor for graphene-based materials. [ABSTRACT FROM AUTHOR]

The applications of chitin are limited due to its insolubility in most organic solvents. The chemical modification of chitin to generate new bio-functional materials can bring more desirable properties. A concentration of 5% can be obtained. We have successfully prepared chitin fibres and spheres by dissolving chitin in 85% phosphoric acid in various coagulating agents and then regenerating it in 10% sodium hydroxide. The change in molecular structure was studied by Fourier Transform Infrared Spectroscopy (FTIR). The surface morphology of different biomaterials was observed using scanning electron microscopy (SEM) and optical microscopy (OM). [ABSTRACT FROM AUTHOR]

Wood colored internally by fungi has long been used by woodcrafters and artisans as a substitute for synthetic dyes. Recent advances in the field of spalted wood have led to methods by which the fungal dyes can be extracted from either a fungal solution or colonized wood and then reapplied to clear wood. This takes the 'guess work' out of spalting, as well as the time necessary for fungal colonization; however, it requires organic solvents like dichloromethane, which are toxic and not readily available to consumers. Herein, the authors show that the dyes can be successfully carried and blended together (to increase the range of colors) in a range of natural oils. The blue-green dye of Chlorociboria species, called xylindein, carried best in raw linseed oil, the red dye of Scytalidium cuboideum performed best in Danish oil, although more dye could be carried in raw linseed oil, and the yellow dye of Scytalidium ganodermophthorum performed best in walnut oil. The ability to carry and mix these dyes in easily purchased, nontoxic oils opens up their use to woodworkers who seek to follow the traditions of spalted wood, but do not have the skills or time to work with live fungal cultures or fungal dyes suspended in toxic organic solvents. [ABSTRACT FROM AUTHOR]

ABSTRACT Alkyl-substituted polyhedral oligomeric silsesquioxane (POSS) cage is combined with 3,4-ethylenedioxythiophene under the same roof. The corresponding monomer called EDOT-POSS is used to get soluble poly(3,4-ethylenedioxythiophene) (PEDOT-POSS) analogue. Both chemically and electrochemically obtained polymers are soluble in common organic solvents like dichloromethane, chloroform, tetrahydrofuran, and so forth. The PEDOT-POSS has somewhat higher band gap (1.71 eV at 618 nm) than its parent PEDOT (1.60 eV at 627 nm) and as expected the PEDOT-POSS exhibits higher optical contrast (74% at 618 nm) and coloration efficiency (582 cm2/C for 100% switching), lower switching time (0.9 s), higher electrochemical stability (93% of its electroactivity retains after 5000 cycles under ambient conditions) when compared to the PEDOT. A number of advantages of the PEDOT-POSS over the PEDOT can make it a promising material in the areas of electro-optical applications. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017, 55, 3935-3941 [ABSTRACT FROM AUTHOR]

In the present study results related to the in vivo administration of Natural Deep Eutectic Solvents (NADES)-solubilized berberine are reported for the first time. NADES are mixtures of small natural compounds having a melting point significantly lower than that of any individual component. Such solvents have gained much attention of the scientific community in the green chemistry area, being considered useful alternatives to common organic solvents. NADES can be used also as administration vehicles, and this can be attractive for nutraceutical products when eutectics are formed with food grade ingredients. In this work, different NADES were prepared using mainly food grade constituents and were tested as solvents for the alkaloid berberine. Three selected NADES/berberine solutions and an aqueous suspension were orally administered to mice with in dose of 50 mg/Kg. Blood levels of berberine were measured by a LC-MS/MS method. The pharmacokinetic analysis revealed a 2-20 fold increase in blood concentration of NADES/berberine with significant changes in pharmacokinetic profile. Natural Deep Eutectic Solvents may thus be considered attractive solubilizing agents and may also play a role in the increase of absorption of poorly bioavailable natural products such as berberine. [ABSTRACT FROM AUTHOR]

The recycling of used, post-industrial and post-consumer PLA is crucial to reduce both the consumption of renewable resources for the monomer synthesis and the environmental impact related to its production and disposal. Several processes are actually available: among these, there is a particular interest on the chemical recycling of PLA with production of its monomer. The aim of this work is to analyse the PLA dissolution behaviour in different organic solvents (acetone and Ethyl lactate) at different water concentrations in order to optimize the chemical depolymerisation process of PLA. New experimental data are presented and a kinetic model is provided for a first analysis. Preliminary results suggest that acetone based solvents (i.e., acetone water mixtures at various concentrations) are more effective to solubilize the PLA rather than the Ethyl-lactate based solvent. Anyway, an increase of water concentration in the solvent phase, determines both a reduction of the solvent power and a reduction of mass transport coefficient for the two solvents tested. [ABSTRACT FROM AUTHOR]

Many solution processing methods of exfoliation of layered materials have been studied during the last few years; most of them are based on organic solvents or rely on surfactants and other funtionalization agents. Pure water should be an ideal solvent, however, it is generally believed, based on solubility theories that stable dispersions of water could not be achieved and systematic studies are lacking. Here we describe the use of water as a solvent and the stabilization process involved therein. We introduce an exfoliation method of molybdenum disulfide (MoS2) in pure water at high concentration (i.e., 0.14 ± 0.01 g L−1). This was achieved by thinning the bulk MoS2 by mechanical exfoliation between sand papers and dispersing it by liquid exfoliation through probe sonication in water. We observed thin MoS2 nanosheets in water characterized by TEM, AFM and SEM images. The dimensions of the nanosheets were around 200 nm, the same range obtained in organic solvents. Electrophoretic mobility measurements indicated that electrical charges may be responsible for the stabilization of the dispersions. A probability decay equation was proposed to compare the stability of these dispersions with the ones reported in the literature. Water can be used as a solvent to disperse nanosheets and although the stability of the dispersions may not be as high as in organic solvents, the present method could be employed for a number of applications where the dispersions can be produced on site and organic solvents are not desirable. [ABSTRACT FROM AUTHOR]

Alginate and its derivatives are annually produced approximately 30,000 tons or more and are applied to various industries as they are natural polymers. The global market for alginate and its derivatives has been growing steadily. There is little research compared to other enzymes produced through biomass degradation or modification. An alginate lyase, MtAl138, from Microbulbifer thermotolerans DAU221 was cloned and identified in Escherichia coli BL21 (DE3). MtAl138 contains a highly conserved motif (R538TELR, Q607IH609, and YFKAGVY716NQ), which indicates that it belongs to the polysaccharide lyase family 7 (PL7). MtAl138, with a molecular weight of 77 kDa worked optimally at 45 °C and pH 7.4. MtAl138 showed twice as much activity as when there was no NaCl when there was between 100 and 600 mM NaCl. Moreover, its activity increased in organic solvents such as benzene, hexane, methanol, and toluene. Based on the thin layer chromatography analyses, MtAl38 is an endo-type enzyme that produces di-, tri-, or tetrasaccharides from polyG and polyM. This study provided that MtAl138 is an endoenzyme that showed outstanding enzymatic activity at concentrated salt solutions and organic solvents, which makes it a reasonably attractive enzyme for use in various industries. [ABSTRACT FROM AUTHOR]

2-Hydroxy-5-nonylacetophenoneoxime is the active component of several commercial extractants that usually also contain the modifier 4-nonylphenol as a result of the manufacturing processes. The aggregation of these components, 2-hydroxy-5-nonylacetophenoneoxime and 4-nonylphenol, as well as their interaction reactions in toluene at 28 °C have been studied by vapor pressure osmometry. Osmometric data have been treated numerically and the results reveal the formation of dimeric species of the components and the interaction between them to give a 1:1 adduct. The corresponding formation constant values are given. Finally, the osmometric behavior of the commercial extractant SME 529 has been studied and interpreted on the basis of the proposed aggregation and interaction model. [ABSTRACT FROM AUTHOR]

The Co(III) complex of 3,6,9,15-tetra-azabicyclo[9.3.1]penta-deca-1,11,13-triene (L1) has been synthesized in DMF and isolated as a blue solid (1) ([L1CoIIIClX]n+, X = Cl−or DMF,n = 1 or 2). Complex1exhibits solution behavior similar to the classic cobalt(II) chloride equilibrium. When1is dissolved in water, the solution is pink and this complex exists as1a, which consists of a cobalt(III) bound toL1and twocis-chlorides with a perchlorate counter-ion to balance the complex charge ([L1CoIIICl2][ClO4]). In contrast, when1is dissolved in DMF or other organic solvents the solution is blue and is observed as1b. The1bcomplex salt contains two cobalt centers. One cobalt(III) is bound toL1, Cl−, and DMF. Charge balance is accomplished by the second cobalt center: [CoIICl4]2−, thus making1b(L1CoIIICl(DMF)][CoIICl4]). This equilibrium was confirmed using UV–visible spectroscopy, EPR, and X-ray crystallography. [ABSTRACT FROM AUTHOR]

The present study elucidates the extended nature of the weak interaction between methanol and chloroform in its mixture using steady-state, ultrafast and single molecule spectroscopic methods. UV-vis absorption spectroscopy using a solvatochromic dye indicates a synergistic solvation in the methanol-chloroform binary solvent mixture, which causes the solvatochromic dye to sense increased polarity compared to the bulk counterparts. Such synergism was not observed in the emission study and is explained by the weak nature of the interaction between methanol and chloroform. Fluorescence anisotropy and single molecule fluorescence spectroscopy are employed to understand the nature of such weak interaction on femtosecond to microsecond time scale. Retardation of both the rotational and translational diffusion of the reporter molecule indicates that the observed weak interaction is extended over large dimension in the condensed phase. [ABSTRACT FROM AUTHOR]

Modified antimicrobial and antifouling materials and surfaces can be used to limit the propagation of microorganisms on various surfaces and minimise the occurrence of infection, transfer, and spoilage. Increased demand for 'green' solutions for material treatment has pushed the focus towards to naturally produced antimicrobials. Tyrocidines, cyclo-decapeptides naturally produced by a soil bacterium Brevibacillus parabrevis, have a broad spectrum of activity against Gram-positive and Gram-negative bacteria, filamentous fungi, and yeasts. Continual losses in tyrocidine production highlighted the possible association of peptides to surfaces. It was found in this study that tyrocidines readily associates with many materials, with a selectivity towards polysaccharide-type materials, such as cellulose. Peptide-treated cellulose was found to remain active after exposure to a broad pH range, various temperatures, salt solutions, water washes, and organic solvents, with the sterilising activity only affected by 1% SDS and 70% acetonitrile. Furthermore, a comparison to other antimicrobial peptides showed the association between tyrocidines and cellulose to be unique in terms of antimicrobial activity. The robust association between the tyrocidines and various materials holds great promise in applications focused on preventing surface contamination and creating self-sterilising materials. [ABSTRACT FROM AUTHOR]

Extraction of microamounts of radioactive cesium and strontium by 25,27-bis(1-octyloxy)calix[4]-26,28-crown-6 (DOC[4]C6) and dicyclohexyl-18-crown-6 (DCH18C6) from nitric acidic solutions into alcohols, ketones and some other solvents was studied. We concentrated on collecting detailed data possibly useful for subsequent evaluations of appropriate schemes and mechanisms. Although not testing in fullness the system with DOC[4]C6 and DCH18C6 in 1-octanol, we present some evidence of its suitability such as fast kinetics, chemical and radiation stability, and invariance of parameters (process stability) after several times repeated batch extraction-strip cycles. Some peculiarities of a possible mechanism of extraction in these systems are reported. [ABSTRACT FROM AUTHOR]

Oily wastewater and soluble contaminants from oil spills, industrial wastewater and domestic sewage have caused serious water pollution. Promisingly, the synergistic treatment technology of adsorption and visible light catalysis is considered to be an effective solution for wastewater purification. In this paper, a dual-functional superhydrophobic polydimethylsiloxane@ZnO@melamine sponge (PDMS@ZnO@MS) was successfully prepared for oil–water separation and photocatalytic degradation of dyes in wastewater. The PDMS@ZnO@MS sponge showed superhydrophobic properties with a water contact angle of 150.5°, and excellent selectivity adsorption for various organic solvents and oils from water. This sponge can effectively separate oil-in-water emulsion. Meanwhile, the sponge has outstanding oil/water separation efficiency (99% after 10 cycles) and oil absorption capacity (2276 wt% after 40 cycles). Notably, the obtained superhydrophobic sponge could withstand chemical corrosion (acid, alkaline, and salt solutions) and demonstrated good thermal stability. Moreover, the PDMS@ZnO@MS sponge was effective for photocatalytic degradation of methylene blue with a degradation efficiency of over 90% under 60 min irradiation. Therefore, the PDMS@ZnO@MS sponge is a promising oil–water separation and photocatalytic material with great potential applications in wastewater remediation. [ABSTRACT FROM AUTHOR]

ABSTRACT Highly ordered porous membranes of cellulose triacetate (CTA) were prepared successfully on ice substrates using breath figure method. The pore size and structure of the membrane were modulated by changing CTA concentrations and substrate materials. As the CTA concentration in the casting solution increased, the pore size in the formed membrane decreased. The regularity of the membrane cast on the ice substrate was much better than that of the membrane cast on glass substrate, because the low temperature of ice substrate slowed down the evaporation rate of organic solvent, which offered enough time for condensed water droplets to self-organize into an ordered array dispersed in the polymer solution before their coagulation. The ordered porous CTA membrane was not only used for microfiltration, but also used for fabrication of functional microstructures. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2015, 53, 552-558 [ABSTRACT FROM AUTHOR]

To facilitate industrial applications, as well as for environmental and health purposes, there is a need to find less hazardous solvents for processing the photoactive layer of organic solar cells. As there are vast amounts of possibilities to combine organic solvents and solutes, it is of high importance to find paths to discriminate among the solution chemistry possibilities on a theoretical basis. Using Hansen solubility parameters (HSP) offers such a path. We report on some examples of solvent blends that have been found by modelling HSP for an electron donor polymer (TQ1) and an electron acceptor polymer (N2200) to match solvent blends of less hazardous solvents than those commonly used. After the theoretical screening procedure, solubility tests were performed to determine the HSP parameters relevant for the TQ1:N2200 pair in the calculated solvent blends. Finally, thin solid films were prepared by spin-coating from the solvent blends that turned out to be good solvents to the donor-acceptor pair. Our results show that the blend film morphology prepared in this way is similar to those obtained from chloroform solutions. [ABSTRACT FROM AUTHOR]

Nowadays, there is a need for new sources of noble metals due to their dwindling natural resources. This paper presents studies on the sorption of noble metals such as Au(III), Pt(IV), Pd(II) and Rh(III) from model chloride solutions on a newly prepared Amberlite XAD-16–Aliquat 336 sorbent. A "warm impregnation" method without the use of toxic organic solvents was applied to impregnate the polymer matrix. The influence of such factors as hydrochloric acid concentration, sorbent mass and phase contact time was investigated. Kinetic as well as adsorption isotherm studies were carried out. The sorption capacity of the synthesized sorbent was Au(III)—94.34 mg/g, Pt(IV)—45.35 mg/g and Pd(II)—46.03 mg/g. Based on thermodynamic considerations, their sorption proved to be endothermic, as the values of ΔH° > 0. Sorption was spontaneous and favourable (ΔG° < 0). After leaching the RAM module, there was obtained a real solution, in which the metal contents were determined: 38.10 mg/g of gold and 1.76 mg/g of palladium. Totals of 99.9% of gold and 45.4% of palladium were removed from the real leaching solution, with other elements in the solution. [ABSTRACT FROM AUTHOR]

Many reactions are carried out in solvent mixtures, mainly because of practical reasons. For example, E2 eliminations are favored over SN2 substitutions in aqueous organic solvents because the bases are desolvated. This example raises the question: how do we chose binary solvents to favor reaction outcomes? This important question is deceptively simple because it requires that we understand the details of all interactions within the system. Solvatochromism (solvent-dependent color change of a substance) has contributed a great deal to answer this difficult question, because it gives information on the interactions between solvents, solute-solvent, and presumably transition state-solvent. This wealth of information is achieved by simple spectroscopic measurements of selected (solvatochromic) substances, or probes. An important outcome of solvatochromism is that the probe solvation layer composition is almost always different from that of bulk mixed solvent. In principle, this difference can be exploited to "tune" the composition of solvent mixture to favor the reaction outcome. This minireview addresses the use of solvatochromic probes to quantify solute-solvent interactions, leading to a better understanding of the complex effects of solvent mixtures on chemical phenomena. Because of their extensive use in chemistry, we focus on binary mixtures containing protic-, and protic-dipolar aprotic solvents. [ABSTRACT FROM AUTHOR]

Objectives  The main aim of the research was to analyze an economical and eco-friendly approach to improve the solubility of norfloxacin. The current analysis was to utilize the hydrotropic solutions to extract the drugs from their dosage forms, avoiding the use of costlier and harmful organic solvents. Materials and Methods  In this study, an ultraviolet–visible spectrophotometer (model 1800, Shimadzu Corporation) was used to analyze the norfloxacin drug. The mixed hydrotropy approach was used to determine the solubility of norfloxacin. In this work, a blend solution (20% of urea + 20% of sodium benzoate) was used as a hydrotropic solubilizing agent. Results  The solubility of norfloxacin drug in water was very low at ∼0.88 mg/mL and the solubility of norfloxacin drug in the blend solution was 11 mg/mL. From 98.96 (tablet II) to 99.35 (tablet I), the percent estimation value was achieved. This value was nearly 100, so the proposed method was correct. Standard deviation (0.2540–0.4156), percentage coefficient of variation (0.2566–0.4183), and the value of standard error (0.1481–0.2415) are also very low; hence, we can say that the proposed method is accurate. Conclusion  To avoid the use of organic solvents, the mixed hydrotropy concept can be used for spectrophotometric estimation of low water-soluble drugs from bulk drug samples. It provides an economical and environmentally friendly mechanism. [ABSTRACT FROM AUTHOR]

Biomass fractionation is important for the further conversion of the cellulosic fraction and the effective utilization of the lignin fraction for the production of biofuels and value-added products. Solvent properties play a crucial role on the fractionation efficiency of lignocellulosics using an organosolv fractionation process catalyzed by acidic ionic liquids (AILs). Herein, 12 organic solvents were selected as co-solvents with water based on their solubility parameters for lignin dissolution, including alcohols, alcohol ethers, lactones, and alkanolamines, in order to fractionate poplar and rice straw. Effects of fractionation liquor solubility parameters on the delignification efficiency of organosolv fractionation were investigated under the same conditions. Relative energy differences (REDs) of the cosolvent systems for lignin dissolution were closely related to the degree of delignification with adjusted coefficients of determination of 0.899 and 0.800 for poplar and rice straw processes, respectively. The application of solubility parameter analysis may provide a rational way to screen solvent or co-solvent fractionation systems for biomass fractionation process. [ABSTRACT FROM AUTHOR]

Deep eutectic solvents (DESs) are beginning to attract interest as electrolyte alternatives to conventional organic solvents and ionic liquids within dye-sensitized solar cells (DSSCs). The precise roles played by DES components and whether they simply represent a benign medium for mobilizing charge carriers or present beneficial functionality that impacts device performance remain unclear. To begin to address this deficiency in understanding, we performed a comprehensive characterization of the three "canonical" choline chloride-based DESs (i.e., reline, ethaline, and glyceline) as DSSC electrolytes hosting the iodide–triiodide (I−/I3−) redox couple. The measurement of electrolyte viscosities, determination of triiodide diffusion coefficients, and photovoltaic performances assessed for water contents up to 40 wt. % allow the emergence of several important insights. A comparison to the observed photovoltaic performance arising from the individual components aids in further clarifying the impact of DES chemistry and solution viscosity on photovoltaic and charge carrier diffusion characteristics. Finally, we introduce the DES guaniline—consisting of a 1:1 molar ratio mixture of choline chloride with guanidinium thiocyanate—demonstrating it to be a superior DSSC electrolyte over those formulated from the three most widely studied canonical DESs at all water contents investigated. [ABSTRACT FROM AUTHOR]