Different Deep Eutectic Solvents Research Articles

Performance evaluation of advanced machine learning methodologies in simulating hydrogen chloride (HCl) absorption by deep eutectic solvents

This work aims to construct the physical-based machine learning (ML) approach for estimating the hydrogen chloride (HCl) solubility in eleven different deep eutectic solvents (DESs). All DES-HCl equilibrium records versus temperatures and pressures are gathered from the literature to ensure ML universality. Then, a well-known feature selection technique was applied to identify the physically meaningful descriptors for the hydrogen bond acceptors (HBA) and hydrogen bond donors (HBD). Afterward, temperature, pressure, selected meaningful physical descriptors, and HBA/HBD molar concentrations are utilized to design ML tools to compute HCl solubility in DESs. Diverse MLs, including extreme learning machines, convolutional neural networks, long short-term memory, cascade neural networks, and extreme gradient boosting (XGBoost), are tested, and their accuracy is compared to select the best candidate. The XGBoost model predictions for HCl solubility in DESs are in acceptable agreement with the literature records. This model precisely simulates 417 DES-HCl equilibrium records in the temperature range of 293–348 K and pressures of up to 127 kPa with a correlation coefficient of 0.99621, mean absolute percentage deviation of 3.04, mean absolute error of 0.448, and root mean square error of 0.729. Results of the designed XGBoost model prove that acetamide-ethylene glycol (1:1), which can averagely dissolve up to 32.47 wt% (weight percent) of HCl, is the best DES for the HCl capture and recovery. After approving the XGBoost model reliability with different visual and numerical inspections, the Leverage method also justified its validity domain by more than 97.6%.

Understanding the interactions between CO[formula omitted] and selected choline-based deep eutectic solvents using density functional theory

The interaction of CO2 with different deep eutectic solvents (DES) has been studied at the molecular level using density functional theory. Choline chloride and choline bromide were selected as the hydrogen bond acceptors (HBA); urea, ethylene glycol and glycerol were selected as the hydrogen bond donors (HBD). The type and intensity of interactions in DES and that between DES and CO2 molecules at various interaction sites as well as the quantification of short-range interactions has been studied using Bader’s quantum theory of atoms in molecules (QTAIM). The distribution of electrostatic potential (ESP) charges during these interactions has been detailed using the Charges from ESP using a grid (CHELPG) scheme. The non-covalent interactions have been identified using the reduced density gradient (RDG) analysis. Strong van der Waals forces were observed to contribute in the formation of DES. The highest interaction energy of −10.65 kcal/mol was found between the DES2 that comprised of choline chloride and ethylene glycol in the molar ratio of 1:2 and the CO2. The results of this study show that both HBA and HBD affect the interaction between CO2 and DES. This study can contribute in designing more specific DES for CO2 capture and utilization.

Efficient conversion of carbohydrates into 5‐hydroxymethylfurfural using choline chloride-based deep eutectic solvents

In this study, the conversion of monosaccharides to 5-hydroxymethylfurfural (5-HMF) using different deep eutectic solvents (DESs) was investigated in various conditions. Among all the investigated DESs, [ChCl][trichloroacetic acid], based on choline chloride and trichloroacetic acid with the ratio 1:1, showed the highest catalytic activity. A maximum 5-HMF yield was 82 % for 1 h at 100 °C using [ChCl][trichloroacetic acid] as a catalyst from fructose. [ChCl][trichloroacetic acid] could be recovered and reused three times with a slight loss in activity. Our work demonstrated the low-cost and effective method for the synthesis of 5-HMF from carbohydrates.

Investigation of supercapacitor electrode performances of phosphorus-doped graphene oxide electrodes in various deep eutectic solvents and symmetric supercapacitor application

A one-step preparation method of phosphorus-doped graphene oxide electrode (P-GOE) was used as electrode material for high-performance supercapacitors. Phosphorus-doped graphene oxides were synthesized on pencil graphite electrodes in one step with easy, cheap, and non-toxic chemicals by using the chronoamperometric process. Electrochemical analyses were carried out to examine the capacitive behavior of the electrodes in different deep eutectic solvents (DESs) (choline chloride:ethylene glycol (ChCl:EG), choline chloride:urea (ChCl:U), choline chloride:phenol (ChCl:Ph)). The electrolytes used make research valuable because these electrolytes were environmentally friendly, non-toxic, and inexpensive. Electrodes were analyzed by cyclic voltammetry at different scan rates, charge-discharge test at different current densities, 1000-cycle galvanostatic charge-discharge test, and electrochemical impedance spectroscopy (EIS). Structural and morphological properties of the electrodes were investigated by FTIR, XRD, SEM, BET, and XPS. As a result of the characterization and electrochemical analysis, it was seen that the phosphorus doping to the electrodes were carried out successfully. The maximum areal capacitances of phosphorus-doped graphene oxide electrodes were calculated to be 450 mF.cm−2, 140 mF.cm−2, and 400 mF.cm−2 in electrolytes for supercapacitor applications. In this study, high-performance P-doped graphene oxide electrodes were produced with an easy method using inexpensive and non-toxic solvents, providing an important contribution as environmentally friendly and sustainable electrode materials for supercapacitor applications.

Sustainable Organocatalyzed Enantioselective Catalytic Michael Additions in Betaine-Derived Deep Eutectic Solvents

AbstractThe organocatalyst cinchonidine-squaramide was immobilized within three different deep eutectic solvents (DESs): betaine:d-sorbitol:water, betaine: d-xylitol:water, and betaine:d-mannitol:water and evaluated in a well-known asymmetric Michael addition. These reactions provided excellent yields (up to 99%) and enantioselectivities (up to 98%) using only 1 mol% of organocatalyst. It was also possible to achieve 9 cycles in reactions with DES (betaine:d-sorbitol:water), proving the high recyclability of this system. In the reactions realized with only 0.5 mol% of organocatalyst, it was possible to achieve 5 cycles, and the products were obtained with high yields (up to 95%) and excellent enantioselectivities (up to 94%), using DES (betaine:d-sorbitol:water).

Detailed investigation of zinc coating behaviours in various deep eutectic solvents

Determining the optimum conditions of a metal coating is significant for its possible applications in many fields. The present work described the electrodynamic process of zinc coating from six different deep eutectic solvents (DESs), especially type-III DES systems prepared with a quaternary ammonium salt and hydrogen bond type. Non-reversible processes without oxidation were found in DES systems prepared with choline chloride and zinc nitrate salts, and also, propylene glycol and zinc nitrate salts, termed as type-II and type-IV, respectively. The most attracted type-III DES prepared by a mixture of 1 molar choline chloride and 2 molar ethylene glycols, commercially known as Ethaline (E200), were examined for its electronucleation and possible reactions for zinc electrodeposition. For the first time, the Pt working electrode was investigated under high-resolution optical microscopy to visualize the in-situ morphology change during oxidation and reduction in E200. Furthermore, the morphological change during the anodic dissolution of zinc was also investigated in situ under a high-resolution microscope. It was found that insoluble species forming during anodic dissolution blocks the surface. Bulk electrolysis was performed in these solvents to investigate the formed zinc nucleates' morphological differences. XRD analysis was performed to differentiate the crystal planes of each deposition obtained from six DESs. It was found that the type-II and type-IV DESs consisting of zinc nitrates revealed zinc hydroxy nitrate dominated zinc deposition, which can be helpful in various applications.

Effects of deep eutectic solvents pretreatment on coal physicochemical characteristics

ABSTRACT Coal is a major resource in China both for chemicals production and power generation, but its impact on the environment demands attention. Solvent pretreatment is an effective method to realize cleaner utilization of coal. Shendong sub-bituminous coal was treated with three different deep eutectic solvents (DESs) – choline chloride (ChCl)-urea, ChCl-glycerol, and ChCl- ethylene glycol – at temperature as low as 120°C. Proximate/ultimate analyses, scanning electron microscopy, thermogravimetric analysis, and Fourier transform infrared spectroscopy were used to examine the physicochemical changes that occurred in coal after DESs treatment. Results showed that DES treatment led to coal fragmentation and decreased average particle size. Compared with raw coal (33.1%), DES-treated coal showed greater mass loss (35.2 − 37.7%), showing that the amount of low molecular mass species increased after treatment. This was confirmed by the observation that DES-treated coal had more volatile components and less minerals and functional groups that contained oxygen (especially C−O). The content of elemental sulfur also decreased from 0.26% to 0.10 − 0.15% after DES treatment, along with a reduction in aliphatic chain length and aromatic substitution degree, which were from 10.73 to 9.33−10.08 and 16.70% to 10.73−15.36%, respectively. The macromolecular structure of the coal was destroyed as a result of DES’s interactions with the weak covalent bonds and hydrogen bonds in the coal. These results suggest that DES has the potential to be used as a pretreatment solvent for coal conversion.

New method for green extraction of ginsenosides based on mechanochemically-assisted extraction and deep eutectic solvents

Ginsenosides are the main active ingredients in ginseng. Studies have shown that ginsenosides have anti-virus, anti-tumor, anti-aging, nootropic, cardiovascular diseases-protecting, and other pharmacological activities. Thus, the development and utilization of ginsenosides have persistently attracted much attention. At present, the extraction of ginsenosides is mainly based on organic solvents, and there are relatively few studies on their green extraction. In this study, different deep eutectic solvents(DESs) were synthesized by heating and stirring method, combined with an emerging technology, mechanochemically-assisted extraction(MCAE), to extract ginsenosides in a green way. Six parameters that might affect the extraction effect were optimized to determine the optimal conditions, and the method validation was conducted. The new established method was compared with a commonly used extraction method(ultrasound-assisted extraction using 70% ethanol) to evaluate its extraction efficiency. The results revealed that the optimal extraction conditions of DES-MCAE were that the volume ratio of DES3(choline chloride∶urea 1∶2) and water in the extraction solvent was 6∶4, and the liquid ratio and the linear vibration speed were 0.05 g·mL~(-1) and 4.0 m·s~(-1); the extraction was performed twice, 40 s each. With only 80 s extraction, the extraction rate of this method was 36.22% higher than that of ultrasoun-dassisted extraction using 70% ethanol. In this study, a DESs-based pretreatment method for ginsenosides was established and its rapid, green and efficient extraction was realized, which provided new ideas and methods for further research on green extraction of other active ingredients from Chinese medicine.

Characterization of carotenoids in Lycium barbarum fruit by using UPC2-PDA-Q-TOF-MSE couple with deep eutectic solvents extraction and evaluation of their 5α-reductase inhibitory activity.

Carotenoids from Lyciu m barbarum fruits have possessed pharmacological efficacy against eye diseases, cardiovascular disorders, cancer, and benign prostatic hyperplasia. However, the efficient extraction, rapid characterization and activities evaluation of Lycium carotenoids remains a challenge. To concentrate and characterize Lycium carotenoids, we have developed ultrasound-assisted extraction methods with different deep eutectic solvents (DESs) and analyzed carotenoids by ultra-performance convergence chromatography coupled with photo diode array detector and quadrupole time-of-flight mass spectrometry (UPC2-PDA-Q-TOF-MSE). DESs containing choline chloride and malonic acid presented better extraction efficiency and were more environmentally friendly than other extraction methods. Carotenoids were more quickly profiled (in 11min) by UPC2 compared to by UPLC (in 35min), with seventeen main peaks were characterized in the MS fragmentation patterns. The in vitro 5α-reductase inhibitory activity of DESs extracts, fractions and components were subsequently assessed, and the predominant component zeaxanthin dipalmitate (ZD) exhibited potent inhibitory activity. Our study provides a chemical and pharmacological basis for the further development of potential new drugs based on Lycium carotenoids.

A Double Action P-D (Polymer-Deep Eutectic Solvent) Based Shale Inhibitor in Drilling Mud

Shale stabilization is very significant during drilling to avoid wellbore stability issues. Water based drilling fluid results into shale swelling on contact with shale formation. Different additives are added in the drilling mud which inhibits the shale swelling by stabilizing the charge on the clay surface. Various polymers and different Deep Eutectic Solvents (DES) have been proven to be successful shale inhibitors, but their performance can be further improved by using a combination of polymer and DES. This research features a double action P-D (Polymer – Deep Eutectic Solvent|) inhibitor formulated by the combination of Potassium Carbonate based DES and modified oxazoline based polymer and compares its inhibition performance with KCl (Potassium Chloride). Linear Swell meter has been used after compressing the Na-Bt (Sodium bentonite) wafers at 1600 psia and swelling results have been analysed after 24 hours. Moreover, surface tension, d-spacing, and Zeta potential of inhibitors-based samples have been measured to justify and understand the swelling results. The results showed P-D inhibitor showed the best inhibition of 76% with maximum decline of 36% and 73% in Surface tension and Zeta Potential respectively. The double action of P-D inhibitor is associated with its capability to form hydrogen bond and exhibit Vander wall forces with the clay surface altogether.

Ecofriendly and enhanced biogenic synthesis of silver nanoparticles using deep eutectic solvent-based green tea extracts

In compliance with green chemistry, metallic nanoparticles can be biogenically synthesized using plant extracts. Herein, three different deep eutectic solvents (DESs) were used instead of water to prepare green tea extracts (GTEs). The resultant DES-based GTEs exerted different beneficial effects on the biosynthesis of silver nanoparticles. Compared with the water-based GTE (W-GTE), the DES-based GTEs contained higher levels of catechins (up to 235% more) that are natural reducing and capping agents and showed higher synthesis efficiency. In particular, two DESs, which consist of glycerol and betaine with a common urea molecule and are designated as GU and BU, respectively, could produce silver nanoparticles with superior properties to water. Specifically, GU- and BU-GTE-based silver nanoparticles showed uniformly reduced sizes, 39.12 (±5.33) nm and 43.11 (±6.42) nm, respectively and homogenous face-centered cubic crystallinity. DESs added to W-GTEs lead to synthesis of silver nanoparticles with improved dispersion. The DES-GTE-based silver nanoparticles at 60 μg/mL displayed in vitro anti-cancer activity comparable to doxorubicin at 12.5 μg/mL. These results suggest that the tested DESs could serve as efficient extraction solvents for phytochemicals as well as effective surface modifiers without posing adverse effects for subsequent applications of the synthesized nanoparticles. The favorable effects of GU and BU were found to partially involve ammonia, which was formed during DES preparation at high temperatures (≥80 °C). This study shows that DESs can promote the biogenic synthesis of silver nanoparticles by playing diverse roles depending on the unique properties of the DESs and their constituents.

Facile fabrication of electrochemically reduced graphene oxide/polythionine-methylene blue and its use as a platform for detection of nicotinamide adenine dinucleotide in the artificial urine sample

Here we report on a facile, rapid, selective, and stable electrochemical sensing platform for nicotinamide adenine dinucleotide (NADH) based on polythionine-methylene blue/electrochemically reduced graphene oxide modified glassy carbon electrode (PTH-MBDES-ERG/GCE). The ERG was directly formed on a glassy carbon electrode (ERG/GCE) through one-step electrochemical reduction of GO in PBS solution (10 mM, pH 7.4). In a PBS electrolyte, respectively, containing 50% (v/v) three different deep eutectic solvents (DES), thionine and methylene blue were polymerized on the surface of ERG/GCE. The electrochemical properties of the polymers polymerized in different electrolytes were investigated. The PTH-MBDES-ERG composite has a higher performance in the electrocatalytic oxidation of NADH than that of PTH-MBDES. The as-prepared PTH-MBDES-ERG/GCE demonstrated excellent direct electrocatalytic oxidation toward NADH, providing a favorable platform for electron transfer from NADH to the electrode. The sensor displayed a wide linear range from 1.52 μM to 3333.33 μM with a limit of detection of 0.51 nM. The interference from the ascorbic acid and uric acid was negligible. The prepared sensor was further tested for the determination of NADH in artificial urine samples, showing the PTH-MBDES-ERG/GCE formed by electropolymerization have promising biomedical applications.

Performance evaluation of deep eutectic solvent for surfactant polymer flooding

Surfactant polymer (SP) flooding is among the most efficient and widely accepted chemical enhanced oil recovery (EOR) processes which involves slug injection containing a polymer and surfactant. This work is aimed at understanding the effect of different deep eutectic solvents (DESs) as an additive for EOR. For this, two different DES have been synthesized, having different hydrogen bond donors and acceptors and their effect on EOR was investigated. The results show that the addition of DESs as surfactant additives significantly improves flooding performance. The addition of DES1 and DES2 at critical micelle concentration (CMC) reduced the surface tension of water by 47% and 43%, respectively. The interfacial tension was drastically reduced upon the addition of DES. Also, DES molecules were found to affect the micellization concentration of surfactants. The addition of 1000 ppm of DES1 and DES2 reduced the CMC of surfactant by 17% and 9% respectively. In addition, DESs reduced the surfactant adsorption by 34% and 22% for DES1 and DES2, respectively. These results show that prepared DESs are highly efficient and outperformed the conventional [C12mim][Cl] and [C4mim][PF6] ionic liquids. The addition of DESs further enhanced the cumulative oil recovery for surfactant polymer flooding.

Deep eutectic solvents and alkaline extraction of protein from seabuckthorn seed meal: a comparison study

Seabuckthorn seed meal (SSM) is a waste of oil extraction industry that rich in protein. In order to seek suitable protein extraction method, three different deep eutectic solvents (DESs) (including choline chloride-glycerol, choline chloride-oxalic acid and choline chloride-urea) were developed for extracting protein from SSM and compared with alkaline. Result indicated that alkaline could effectively extract 56.9% protein from SSM and its protein content was 73.1%, higher than DES at 31.0%41.4% and 64.3%67.5%, respectively. However, compared to alkali, DES led to a product with less β-sheet, more β-turn, more essential amino acids, higher total amino acid content, especially choline chloride-urea which extracted protein showing an integrated and similar protein weight distribution compared to SSM. Also, this protein extracted chloride-urea showed a highest digestibility in vitro (by pepsin) (54.2%). These results indicated that choline chloride-urea extraction is better than alkaline extraction for SSM.

Efficient fractionation of bamboo residue by autohydrolysis and deep eutectic solvents pretreatment

Bamboo processing residue, which is rich in parenchyma cells, was treated as huge waste in bamboo processing industry, such as reassemble bamboo and bamboo flooring. Herein, autohydrolysis and rapid different deep eutectic solvents (DES) delignification strategy were consecutively performed to remove hemicelluloses and lignin from bamboo processing residue. The xylooligosaccharides (XOS) with high yield (34.35%) was achieved in the autohydrolysis process. Results showed that alkaline DES pretreatment resulted in the highest glucose yield (88.22%) and relatively high delignification rate (83.75%) as well as well-preserved lignin structures. However, the lignin fractions obtained under acidic DES conditions were tending to assemble into lignin nanoparticles (LNPs) and having excellent antioxidant activity as compared to those obtained from alkaline DES system. In brief, the combination of autohydrolysis and rapid DES delignification can achieve orientated fractionation of the components from the industrialized bamboo.

Optimization of Deep Eutectic Solvent Extraction of Phenolic Acids and Tannins from Alchemilla vulgaris L.

Alchemilla vulgaris L. is a good source of antioxidant components with an emphasis on phenolic acids and tannins. In this study, gallic acid, ellagic acid, and hydrolyzable tannins (HT) were extracted from this plant with different deep eutectic solvents (DESs), varying the amount of added H2O, temperature and extraction time. Seventeen DESs (n = 3) were used for the extraction, of which choline chloride:urea (1:2) proved to be the most suitable. The selection of the best solvent was followed by the examination of the influence of the extraction type and parameters using response surface methodology (RSM). Gallic acid content was in the range of 0.00–1.89 µg mg−1, ellagic acid content was 0.00–12.76 µg mg−1 and hydrolyzable tannin (HT) content was 3.06–181.26 µgTAE mg−1, depending on the used technique and the extraction conditions. According to the results, extraction by stirring and heating was the most suitable since the highest amounts of gallic acid, ellagic acid, and HT were extracted, and the obtained optimal values using response surface methodology (RSM) are confirmed by experimentally obtained values.

Liquid-liquid separation of n-hexane/1-hexene and cyclohexane/cyclohexene using deep eutectic solvents

In this study, the feasibility of twelve different deep eutectic solvents (DESs) in separating olefins from paraffins was investigated. The DESs were prepared by combining choline chloride (ChCl) or tetrabutyl ammonium bromide (TBAB) with six different hydrogen bond donors. The preliminary COSMO-RS screening revealed that TBAB/TEG (1:4) DES has the high performance index (PI) for both systems. This performance was confirmed by experimental tests at 20% molar ratio of olefins in the feed mixture with the twelve DESs. When TBAB is used, the best distribution ratios were obtained for cyclohexane/cyclohexene system, however for hexane/1-hexene system high selectivities were gotten. In comparison with the performance of ionic liquids, TBAB-based DESs showed better distribution ratios and comparable selectivity. For the cyclohexane/cyclohexene system, TBAB-based DESs exhibited high distribution ratios because of their hydrophobic character represented by butyl chain. In the case of hexane/1-hexene system, TBAB-based DESs are more selective to 1-hexene due to the affinity of TBAB chain and positive charge bringing by ammonium group and 1-hexene. The liquid–liquid equilibrium (LLE) was explored for two ternary systems of {hexane (1) + 1-hexene (2) + DES (3)} and {cyclohexane (1) + cyclohexene (2) + DES (3)} at 298.15 K and 101 kPa using TBAB/TEG (1:4) DES. Furthermore, the NRTL model was successfully used to correlate the experimental LLE data and good predictions were obtained with COSMO-RS for both selected systems. Finally, the extraction mechanism was elucidated by applying 1H NMR analysis and no DESs were found in the raffinate phase.

Unveiling structure-function relationships in deep eutectic solvents based biomimetic catalysis for aerobic oxidative desulfurization

Organic sulfides in fuel oil result in the formation of environmentally hazardous sulfur oxide through the combustion in vehicle engine. Oxidative desulfurization is considered to be an effective technique to eliminate sulfides in fuel oil, whose core is the construction of efficient catalytic systems under mild conditions. Herein, a biomimetic catalytic system was designed for aerobic oxidative desulfurization via coupling ammonium molybdate polyoxometalate with four different deep eutectic solvents (DESs), obeying multi-step electron transfer mechanism. It was found that the desulfurization efficiency was not directly associated with conductivity, viscosity and hydrogen-bonding strength. In combination with density functional theory (DFT) calculation, the difference in desulfurization efficiency was ascribed to the distinguished intrinsic oxidation ability of organic acid in DES. The optimal catalytic system not only could resist the adverse effect of naphthaline and indole within suitable concentration scope, but also did not show obvious decrease in desulfurization performance after ten runs. More importantly, deep desulfurization was still afforded for actual diesels using this catalytic system, indicating its enormously potential applications on an industrial level under mild conditions.

Air-assisted liquid-liquid microextraction of total 3-monochloropropane-1,2-diol from refined edible oils based on a natural deep eutectic solvent and its determination by gas chromatography-mass spectrometry

In this paper, a fast, sensitive, and selective sample preparation procedure was presented for the determination of 3-monochloropropane-1,2-diol (3-MCPD) in refined edible oils using gas chromatography-mass spectrometry. In this method, firstly, the sample lipids and analyte fatty esters are saponified by sodium hydroxide under sonication. After that the analyte was derivatized using phenylboronic acid (as the derivatization agent) and the obtained derivative was extracted during an air-assisted liquid-liquid microextraction procedure (AALLME). Six different deep eutectic solvents (DESs) were prepared as the extraction solvents and the most effective extraction for 3-MCPD was obtained in the presence of a natural DES (NDES) consisting of choline chloride (ChCl)-acetic acid (AcOH). Important variables such as sodium hydroxide concentration and volume, sonication time, temperature, extraction solvent type and volume, and phenylboronic acid concentration and volume have been optimized. Using the optimum conditions, broad linear range (0.88-1000 ng g–1), suitable coefficient of determination (0.995), and low limits of detection (0.26 ng g–1) and quantification (0.88 ng g−1) were obtained. Relative standard deviations for intra– (n=8) and inter-day (n=6) precisions at a concentration of 5 ng g−1 were 2.6 and 3.2%, respectively. The developed method has been successfully applied to 3-MCPD determination in refined edible oil samples including sunflower, corn, and canola oils.

Green microfluidic liquid-phase microextraction of polar and non-polar acids from urine.

In this work, hippuric acid (log P = 0.5), anthranilic acid (log P = 1.3), ketoprofen (log P = 3.6), and naproxen (log P = 3.0) were simultaneously extracted by a green microfluidic device based on the principles of liquid-phase microextraction (LPME). Different deep eutectic solvents (DESs) were investigated as supported liquid membrane (SLM), and a mixture of camphor and menthol as eutectic solvents in the molar ratio 1:1 was found to be highly efficient for the simultaneous extraction of non-polar and polar acidic drugs. LPME was conducted for 6min per sample. Urine sample was delivered to the system at 1μLmin-1, and target analytes were extracted exhaustively (75-100% recovery) across the DES SLM, and into pure aqueous phosphate buffer pH11.0 delivered as acceptor at 1μLmin-1. The acceptor was analyzed with liquid chromatography-UV detection. Interestingly, the DES enabled extraction of both the polar and non-polar model analytes at the same time; all chemicals were green and non-hazardous, and the chemical waste was less than 1mg per sample.