Effect Of Deep Eutectic Solvents Research Articles

Deep Eutectic Supramolecular Polymers: Bulk Supramolecular Materials.

Application of new strategies for supramolecular self-assembly can significantly impact the properties and/or functions of supramolecular polymers. To realize a facial strategy for the development of solvent-free supramolecular polymers in bulk, "deep eutectic solvents" were employed. Cyclodextrins and natural acids were used to prepare deep eutectic supramolecular polymers (DESPs). Deep eutectic solvents have special characteristics that endow DESPs with unique macroscopic properties and excellent processability. DESPs exhibit supramolecular adhesion and temperature-dependent behavior originating from the combined effects of deep eutectic solvents and supramolecular polymerization. Because DESPs are solvent-free and display interesting macroscopic properties, they have potential as new adaptive materials.

The Effect of Deep Eutectic Solvents as Co-solvent on Organophosphorus Hydrolase Targeting Engineering Enzyme-catalyzed

Deep eutectic solvents (DESs) are systems formed from one or more compounds in a mixture form, to give a eutectic with a melting point much lower than either of the individual components. DESs have attracted considerable attention as green alternative solvents to conventional solvents because they are not only eco-friendly, non-toxic, and biodegradable organic compounds, but also low cost and easy to produce.and share several features and properties. DESs not only have particular properties in comparison with traditional organic solvents, but also their combination with organic solvents may also show improved and desired properties. In this study, DESs were used as the solvent in buffer containing organophosphorus hydrolase enzyme, in order to optimize the enzyme reaction buffer. Different DESs such as reline (choline chloride 2:1 urea), ethaline (choline chloride 2:1 ethanol) and glyceline (choline chloride 2:1 glycerol) were selected as an adjuvant for OPH enzyme reaction buffer. Biochemical properties, thermal stability and half-life of the OPH enzyme were studied, accordingly. In the reline, a reduction in the activity of the enzyme and in ethaline and glyceline, an increase in the activity and the stability were observed when compared with the buffer. The highest activity and stability in ethaline and glyceline in molar fraction was 0.025 and 0.25, respectively.

Remarkable effects of deep eutectic solvents on the esterification of lactic acid with ethanol over Amberlyst-15

Deep eutectic solvents (DESs) are widely used in numerous reactions both as a solvent and a catalyst. In this study, different types of DESs were investigated as a supplementary component for Amberlyst-15 to enhance its catalytic activity in the esterification reaction of lactic acid with ethanol. The effects of the following parameters such as DES type, choline chloride: glycerol (ChCl-Gly) (1 : 2) amount, molar ratio of reactants, temperature and agitation rate on the initial rate of reaction and yield of ethyl lactate were investigated. According to the results, DESs alone did not have any catalytic effect on the esterification; however, DESs together with Amberlyst-15 provided a significant increase in the initial rate of reaction and yield. The activation energy of the reaction decreased significantly with the combined use of Amberlyst-15 and ChCl-Gly (1 : 2). Internal and external mass transfer limitations were found to be negligible under optimum reaction conditions.

Tailor-made natural deep eutectic solvents for green extraction of isoflavones from chickpea (Cicer arietinum L.) sprouts

Natural deep eutectic solvents (DESs) have received increasing attention in recent years as emerging green solvents for efficient extraction of bioactive compounds from natural resources. In this study, we aimed to evaluate the potential and effectiveness of DESs with different polarities for extraction of isoflavones from chickpea sprouts. To this end, we examined 20 different DESs based on choline chloride, betaine, and l-proline as hydrogen bond acceptors in combination with different hydrogen bond donors (carboxylic acids, alcohols, sugars, and amine). Extraction efficiency was evaluated based on the extraction yields of four isoflavones (ononin, sissotrin, formononetin, and biochanin A), total flavonoid content, and anti-oxidant activity. On the basis of the results obtained, choline chloride-based DESs containing propylene glycol as a hydrogen bond donor (molar ratio of 1:1) with 30% (v/v) of water was the most effective at extracting isoflavone compounds from chickpea sprouts, compared to conventional solvents. Subsequently, in order to examine the factors contributing to optimal ultrasound-assisted extraction conditions, a Box-Behnken design paired with response surface methodology was implemented. DES water content and extraction temperature were accordingly found to have prominent effects on the extraction yields of isoflavones. Our results indicate that DESs can be used as suitable green solvents for extracting bioactive compounds from various biomaterials.

Effective devulcanization of ground tire rubber using choline chloride-based deep eutectic solvents

The effect of deep eutectic solvents (DES) in devulcanization of ground tire rubber (GTR) was explored for the first time in this work. Three different DESs, namely ChCl:Urea, ChCl:ZnCl2 and ZnCl2:Urea were prepared and their physicochemical properties were examined. GTR was mixed with various DESs which were further sonicated and heated at various time intervals. The treated GTR was analyzed by energy dispersive X-ray (EDX), Fourier transform infrared spectroscopy (FTIR), field emission scanning electron microscope (FESEM) and thermogravimetric analysis (TGA). Additionally, the extent of devulcanization was assessed using soluble fraction, cross-link density and related by Horikx theory. The relation between DESs’ viscosities towards devulcanization efficiency was also evaluated.

Green and efficient extraction of different types of bioactive alkaloids using deep eutectic solvents

Deep eutectic solvents (DESs) have attracted increasing attention as eco-friendly and efficient alternatives to conventional organic solvents. In this study, five herbal medicines (HMs) including Caulis sinomenii, Coptis chinensis, Stephania tetrandra, Tetradium ruticarpum, and Sophora flavescens were selected for the first time to comprehensively evaluate the potential and effectiveness of DESs on the extraction of Morphinane, Protoberberine, Bisbenzylisoquinoline, Indole and Quinolizidine alkaloids, respectively. A total of 75 types of binary or ternary DESs with different polarity, viscosity, pH, and solubilization abilities were tailored to screen a suitable DESs for extraction of morphinane alkaloids from Caulis sinomenii, and the extraction conditions were optimized using response surface methodology (RSM) and artificial neural network hybridized with genetic algorithm (ANN-GA) for the first time. The results demonstrated that DESs were excellent solvents for extraction of alkaloids with superior efficiency to conventional extraction solvents. Moreover, both ANOVA and sensitivity analysis demonstrated that the most critical parameter for alkaloids extraction was water content in DESs. This study reveals the potential of eco-friendly DESs for applications involving the efficient extraction of bioactive alkaloids from natural sources.

Effect of deep eutectic solvent in proton conduction and thermal behaviour of chitosan-based membrane

This work aims to study the effect of choline chloride (ChCl) and urea based deep eutectic solvent (DES) on the proton conduction and thermal properties of chitosan-carboxymethylcellulose (Chitosan-CMC) membrane. Chitosan-CMC biocomposites were prepared in different ratios of 5:95, 10:90, 25:75, 50:50 and 75:25 with DES and was characterised. This study showed a positive improvement the proton conductivity without excessive swelling using DES in comparison with those without DES, with a slight trade-off on the thermal stability. The sample corresponding to 50 wt% of chitosan showed the highest proton conductivity of 1.57 × 10−2 S/cm, which was slightly lower compared to Nafion-117 membrane (8.6 × 10−2 S/cm). The study revealed the blend film with 75 wt% of chitosan with the presence of DES has a potential for polymer electrolyte membrane (PEM) with a low but sufficient water uptake of 49.4% to avoid structural disintegration despite a lower proton conductivity obtained.

The effect of deep eutectic solvents on the asymmetric hydrolysis of styrene oxide by mung bean epoxide hydrolases

BackgroundDeep eutectic solvents have attracted considerable attention in numerous fields. There is little information on mung bean epoxide hydrolase-catalyzed epoxides in deep eutectic solvent-containing system.ResultsAdding deep eutectic solvents with hydrogen bond donor of acids to phosphate buffer resulted in an obvious decrease in the optical purity of product; nevertheless, the relative slight change was observed by the addition of the deep eutectic solvents with hydrogen bond donor of alcohols and urea. Of the tested deep eutectic solvents, 10% additional amount of choline chloride/trithylene glycol can cause a significant improvement in the enantiopurity of product, from 83.2 ± 1.3% to 87.9 ± 0.3%. Moreover, with the increase in the addition amount of choline chloride/triethylene glycol from 10 to 30%, the enantiomeric excess of product enhanced from 87.9 to 94%, but a decline of product yield was observed. Finally, the evaluation of enzyme stability showed that the additional amount from 10% to 30% was not beneficial to the activity recovery.ConclusionIn short, adding choline chloride/triethylene glycol contributes to the improvement in the optical purity of (R)-1-phenyl-1, 2-ethanediol in the catalysis of styrene oxide by mung bean epoxide hydrolases; meanwhile, the enzyme immobilization could be essential.

Improved effect of deep eutectic solvents on polymeric film of surfactant: application in determination and discrimination of dihydroxybenzene isomers as model molecules

The simultaneous determination of hydroquinone and catechol with different deep eutectic solvents (DESs) employed in the polymerization step of cetyltrimethylammonium bromide (CTAB) on an oxidized glassy carbon electrode is studied.

The effect of deep eutectic solvent on the pharmacokinetics of salvianolic acid B in rats and its acute toxicity test.

Deep eutectic solvent (DES), the benign green solvent with uniquely physical properties, has been widely applied in various fields. Our previous study indicated that DES could improve the stability and extraction efficiency of salvianolic acid B (SAB). In this work, with SAB as a model drug, the feasibility of DES as a drug carrier for oral preparation was investigated by evaluating the influence of DES on the pharmacokinetics of SAB and the toxicity of DES. Acute oral toxicity test illustrated that choline chloride-glycerol (ChCl-GL, molar ratio 1:2) was non-toxic with the median lethal dose of 7733mg/kg. To comparison the difference of pharmacokinetics between SAB dissolved in ChCl-GL (1:2) and in water, a rapid and sensitive ultra-performance liquid chromatography coupled with mass spectrum was established to determine SAB and its metabolites in rat plasma. The method validation was also tested for the specificity, linearity (r2>0.9980 over two orders of magnitude), precision (intra-day relative standard deviation (RSD)<2.73% and inter-day RSD<7.72%), extraction recovery (70.96-80.78%) and stability under three different situations. Compared to water, the pharmacokinetic parameters clarified that ChCl-GL (1:2) could promote the absorption of SAB, the peak concentration (Cmax) of 0.308±0.020mg/L was slightly higher than 0.277±0.024mg/L (SAB dissolved in water), and the peak time (Tmax) was significantly decreased from 30min (SAB dissolved in water) to 20min. There was no significant difference on the metabolites between SAB dissolved in ChCl-GL (1:2) and in water. This is the first report on the pharmacokinetic study of DES as a candidate of drug carrier, and the results provide a meaningful basis for the application of DES in pharmaceutical preparation.

Potential use of deep eutectic solvents to facilitate lignocellulosic biomass utilization and conversion

High reliance on crude oil for energy consumption results in the urgent need to explore and develop alternative renewable sources. One of the most promising routes is the transformation of biomass into biofuels and chemicals. The introduction of deep eutectic solvents in 2004 received a considerable amount of attention across different research fields, particularly in biomass processing. The effectiveness of deep eutectic solvents in breaking down the recalcitrant structure in biomass highlights its impact on the transformation of biomass into various value-added products. In addition, deep eutectic solvents are widely regarded as promising “green” solvents due to their low cost, low toxicity, and biodegradable properties. In this paper, some background information on lignocellulosic biomass and deep eutectic solvents is given. Furthermore, the roles of deep eutectic solvents in biomass processing are discussed, focusing on the impacts of deep eutectic solvents on the selectivity of chemical processes and dissolution of biomass. This review also highlights the advantages and limitations of deep eutectic solvents associated with their usage in biomass valorization.

The effect of deep eutectic solvents on catalytic function and structure of bovine liver catalase

Aqueous solutions of reline and glyceline, the most common deep eutectic solvents, were used as a medium for Catalase reaction. By some spectroscopic methods such as UV–vis, fluorescence and circular dichroism (CD) function and structure of Catalase were investigated in aqueous solutions of reline and glyceline. These studies showed that the binding affinity of the substrate to the enzyme increased in the presence of 100mM glyceline solution, which contrasts with reline solution that probably relates to instructive changes in secondary structure of protein. Meanwhile, enzyme remained nearly 70% and 80% active in this concentration of glyceline and reline solutions respectively. In the high concentration of DES solutions, enzyme became mainly inactive but surprisingly stayed in nearly 40% active in choline chloride solution, which is the common ion species in reline and glyceline solvents. It is proposed that the chaotropic nature of choline cation might stop the reducing trend of activity in concentrated choline chloride solutions but this instructive effect is lost in aqueous deep eutectic solvents. In this regard, the presence of various concentrations of deep eutectic solvents in the aqueous media of human cells would be an activity adjuster for this important enzyme in its different operation conditions.

Stabilizing Effects of Deep Eutectic Solvents on Alcohol Dehydrogenase Mediated Systems

Stabilizing Effects of Deep Eutectic Solvents on Alcohol Dehydrogenase Mediated Systems

Prediction of refractive index and density of deep eutectic solvents using atomic contributions

Deep eutectic solvents (DESs) are considered as potential alternatives for ionic liquids (ILs). The evaluation of DESs as new generation of solvents for various practical application requires enough knowledge about some main physical, chemical, and thermodynamic properties. In this study, due to lack of data for DESs’ refractive indices, the refractive indices of twenty four DESs based on ammonium and phosphonium salts were measured and predicted using atomic contribution method. The atomic contributions data for molar refraction proposed by Wildman and Crippen which was developed for neutral compounds were employed to calculate the molar refractions of DESs. Subsequently, the refractive indices of DESs were predicted using Lorentz–Lorenz equation through the calculated DESs’ molar refractions and experimental DESs’ densities values. The absolute relative percentage error (ARPE) value of 0.56% and a regression coefficient (R2) value of 0.9822 both confirmed the highly possible application of the proposed method for predicting the refractive indices. In addition, the effect of DESs’ composition on refractive index of DESs was investigated and it was found that the refractive index of the DESs lies between that of the salt and HBD. Moreover, the densities of DESs were also predicted using Lorentz–Lorenz equation employing the calculated molar refraction and values of experimental DESs’ refractive indices. The ARPE of 1.43% shows that this method for prediction of densities of the synthesized DESs is applicable as well.