Ionic Liquid Aqueous Two-phase System Research Articles

Phase behavior of aqueous two-phase systems formed with cholinium-based magnetic ionic liquids: Experimental insights and theoretical correlations

In this work, three cholinium-based MILs were synthesized, characterized and successfully applied to construct the magnetically responsive aqueous two-phase system (ATPs). This ATPs combined the advantages of ILs and magnetic responsiveness, and showed great potential in the field of extraction and separation. Phase behavior for the magnetic ionic liquid aqueous two-phase systems (MIL-ATPSs) containing [N 1 1n 2OH] [TEMPO-OSO3] + salts + water was investigated experimentally at different temperatures. Merchuk equation was adopted to fit the experimental binodal data with satisfactory correlation performances. The effects of the structure of MILs, temperature and types of salts on the phase behavior were evaluated. Investigation on the phase separation mechanism showed that the phase formation was affected by the structure and viscosity of MILs. The salting-out effect is recognized as the major force for phase separation, which is closely related to the Gibbs free energy of hydration (ΔhydG) and entropy of hydration (ΔhydS) of salts. In addition, a larger biphasic area was obtained by increasing the temperature, indicating the phase separation process was endothermic and entropically driven. The binodal curve at different temperature confirms that this MIL-ATPs has low critical solution temperature (LCST) phase transition behavior. All these experimentally measured data and the theoretical correlations can provide meaningful and valuable information that may promote further research and application.

Effective separation of protein from Polygonatum cyrtonema crude polysaccharide utilizing ionic liquid tetrabutylammonium bromide.

Extraction of plant polysaccharides often results in a large amount of proteins, which is hard to eliminate from the crude extract, and conventional approaches for deproteinization are time-consuming and often involve hazardous organic solvents. In this study, ionic liquid tetrabutylammonium bromide (TBABr) was used to create an ionic liquid aqueous two-phase system (ILATPS) for the separation of the polysaccharide (PcP) and protein extracted from the rhizome of Polygonatum cyrtonema. Bovine serum albumin (BSA) was first applied to assess the feasibility of the ILATPS, and MgSO4 was determined to be the most suitable inorganic salt. By adopting the Taguchi experiment with an L9 (3^4) orthogonal array, it was found that the best condition for the efficient separation of crude PcP was at 25°C, with 1.5g of TBABr, 15mg of PcP, and 2.0g of MgSO4, with the extraction efficiency for the protein and polysaccharide as 98.6% and 93.5%, respectively. The purified PcP was homogeneous, and its weight average molecular weight (Mw) was 7,554Da. Monosaccharide composition analysis indicated the PcP comprised mannose, galactose, glucose, galacturonic acid, arabinose, and rhamnose at a molar ratio of 33:13:8:3.5:2:1. This approach offers a practical tactic to purify polysaccharides of plant origin.

PH-Regulated reversible phase inversion of poly(ionic liquid) aqueous two-phase systems.

Smart aqueous two-phase systems (ATPSs) were fabricated using ferrocenyl and benzyl-modified poly(ionic liquid)s for the first time. The novel ATPSs were found to be pH-sensitive. The upper phase and lower phase could be inverted reversibly by adjusting the pH value of the ATPSs.

Efficient Separation of Proteins and Polysaccharides from Dendrobium huoshanense Using Aqueous Two-Phase System with Ionic Liquids.

By applying the hydrophilic ionic liquid, 1-butyl-3-methylimidazolium chloride ([C4mim]Cl), and inorganic salts (K3PO4), an ionic liquid aqueous two-phase system (ILATPS) was established for the separation of Dendrobium huoshanense polysaccharides (DhPs) and proteins. The effects of inorganic salt concentration, IL quantity, crude DhPs concentration, pH value and temperature were studied to achieve the optimal condition. With the best combination of ILATPS (1.75 g K3PO4, 1.25 g [C4mim]Cl, 10 mg crude DhPs and 5.0 mL ddH2O at pH 7.0 under 25 °C), the extraction efficiency rates for DhPs and proteins were 93.4% and 90.2%, respectively. The processed DhPs retrieved from the lower salt-rich phase comprised mannose, glucose, galactose, arabinose, and galacturonic acid with a molar ratio of 185:71:1.5:1:1 and the molecular weight was 2.14 × 105 Da. This approach is fast, simple and environmentally friendly. It provides a new insight into purifying functional polysaccharides of plant origin.

Extraction and recovery of phenolic compounds from aqueous solution by thermo-separating magnetic ionic liquid aqueous two-phase system

• Thermo-separating magnetic ionic liquids are discovered for the first time. • The first thermo-separating magnetic ionic liquid aqueous two-phase system is successfully developed. • This system is successfully applied to remove phenols from aqueous solution. • MIL and phenolic compound are simultaneously recovered simply by heating. • MIL can be recycled for at least 6 times with satisfactory performances. In this report, thermo-separating magnetic ionic liquids (MILs) were discovered for the first time. Two Polypropylene glycol 600 (PPG 600 ) based thermo-separating MILs were synthesized, characterized and successfully applied to construct the first reported thermo-separating magnetic ionic liquid aqueous two-phase system (MILATPS). This novelly proposed thermo-separating MILATPS combined the advantages of rapid extraction, volatile organic solvent free, magnetic separation and thermo-recovery of MIL in an extraction process. Phase behaviors and extraction-recovery processes of phenol, o -cresol and m -cresol were systematically studied. Several influencing factors on phenolic compound extraction efficiencies were detailedly investigated and optimized. Under optimal conditions, both two synthesized thermo-separating MILs revealed good performances with extraction efficiencies higher than 90%. Scale-up studies were also satisfactory. Additionally, both high purities of MILs and phenolic compounds could be ideally recovered simply by heating and the recoveries of phenolic compounds were higher than 95% for all systems. Furthermore, the two MILs could be recycled for at least 6 times with steadily high extraction efficiencies. This novelly proposed thermo-separating MILATPS is simple and green method which is showing great potential in an extraction-recovery process and the industrial treatment of phenolic wastewater.

Liquid-liquid equilibria for (polypropylene glycol 400 based magnetic ionic liquids + inorganic salts) aqueous two-phase systems at 298.15 K

Two polypropylene glycol 400 (PPG400) based temperature-sensitive magnetic ionic liquids were successfully used to construct the temperature-sensitive magnetic ionic liquid aqueous two-phase systems (MILATPs). This temperature-sensitive MILATPs combined temperature-controlled recovery and the advantages of a MILATPs and is showing great potential in the field of extraction and separation. In this work, aqueous two-phase equilibrium data of the temperature-sensitive MILATPs ([HOPPG400BMIM][Tempo-OSO3] + K3PO4/K2CO3/ Na2CO3 + H2O systems and [BMIMPPG400BMIM][Tempo-OSO3]2 + K3PO4/K2CO3/ Na2CO3 + H2O systems) were determined at 298.15 K under 0.1 MPa. Three common empirical equations including Merchuk equation were adopted to fit the experimental binodal data with satisfactory correlation performances. Inorganic salts screening demonstrated that K3PO4 and K2CO3 have better phase-forming ability than Na2CO3. Morever, [HOPPG400BMIM][Tempo-OSO3] has a better phase-forming ability than [BMIMPPG400BMIM][Tempo-OSO3]2. Subsequently, tie line data for systems containing K3PO4 or K2CO3 were determined and correlated by two empirical equations with satisfactory correlation performances. Furthermore, the temperature- controlled recovery of temperature-sensitive magnetic ionic liquid was ideally realized simply by heating. All these experimentally measured liquid–liquid equilibrium data and the theoretical correlations can provide valuable reference for future application in the field of extraction and separation.

Removal and recovery of triphenylmethane dyes from wastewater with temperature-sensitive magnetic ionic liquid aqueous two-phase system

In this report, temperature-sensitive magnetic ionic liquids (MILs) were discovered for the first time. Two polypropylene glycol 400 (PPG400) based temperature-sensitive MILs were synthesized, characterized and successfully applied to construct the first reported temperature-sensitive magnetic ionic liquid aqueous two-phase system (MILATPs). To the best of our knowledge, this proposed temperature-sensitive MILATPs combined the advantages of rapid extraction, organic solvent free for the whole process, magnetic separation and thermo-recovery of MIL in a separation process for the first time. Temperature-sensitive MILATPs were successfully applied for the removal and recovery of three triphenylmethane dyes from wastewater. Phase behaviors and several influencing factors on dye extraction efficiency were detailedly investigated and optimized with good performances. Both high purities of MIL and dye could be ideally recovered simply by heating and the recoveries of dyes were higher than 93%. Additionally, the two MILs could be recycled for at least 6 times with steadily high extraction efficiencies. Furthermore, this novel temperature-sensitive MILATPs had been successfully applied for real industrial dyed wastewater treatment with satisfactory recoveries of both MIL and dye. This novelly proposed temperature-sensitive MILATPs is simple and green method which is showing great potential in a separation-recovery process and the industrial treatment of dyed wastewater.

Subcritical Ethanol-Water and ionic liquid extraction systems coupled with multi-frequency ultrasound in the extraction and purification of polysaccharides

ABSTRACT This study obtained crude sorghum leaf sheath polysaccharide (39.99% wet matter (wm)) by subcritical ethanol-water (40% v/v) extraction (180°C, 40 min). The subcritical extraction solution was transformed into an ionic liquid aqueous two-phase extraction system and subsequently coupled with ultrasound extraction to obtain partially purified polysaccharides (PPP). PPP yields of 20.89%, 27.38%, and 36.49% (wm) were obtained using 60 kHz, 20/60 kHz, and 20/40/60 kHz ultrasound frequencies, respectively. Polysaccharide functional groups such as hydroxyl, aldehyde, and amide were detected using Fourier Transform Infrared Spectroscopy (FT-IR). Amylose contents of 15%, 18%, and 25% were obtained for PPP under single, dual, and tri-frequencies, respectively. Amylose contents were associated with aggregation of PPP particles sizes after heat exposure (70°C for 1 h 50 min). Triple-frequency extracted polysaccharides with the highest uronic acid (1.51%) and polyphenolic (27.79%) contents had an IC50 of 1.37 mg/mL in an in-vitro hydroxyl scavenging activity assay. Three interesting co-extracted bioactive phytochemicals; 2-amino-5[(2-carboxy)vinyl]-Imidazole, N-[4-bromo-n butyl]-2-Piperidinone, and 3-Trifluoroacetyl Pentadecane were detected. The PPP extract showed antioxidant activity and contained phytochemicals with potential antimicrobial and antiviral activities, and thus may be useful in food, nutraceutical, and pharmaceutical applications.

Determination and correlation of phase equilibria of chiral magnetic ionic liquid aqueous two-phase systems with different inorganic salts at 298.15 K

Three novel chiral magnetic ionic liquids (MILs) with L-Pro anion were synthesized and applied to construct chiral magnetic ionic liquid aqueous two-phase systems (chiral MILATPs). This is the first reported chiral MILATPs and is showing great potential in the extractive resolution of racemic amino acids. In this work, aqueous two phase equilibrium binodal data of these chiral MILATPs ([CnMIM-Tempo][L-Pro](n = 2–4) + K2CO3/K3PO4/Na2CO3/Na2SO4 + H2O) were measured at temperature of 298.15 K. Three classical empirical equations including Merchuk equation were applied for the correlation of the experimental binodal data to obtain the binodal curve. Satisfactory correlation performances were achieved. The screening of inorganic salt revealed that K2CO3 and K3PO4 are better salting-out reagents than Na2CO3 and Na2SO4. Investigation of chiral MIL species demonstrated that chiral MIL with longer alkyl chain length of cation has better phase forming ability when the values of n are in the ranges of 2–4. Moreover, tie-line data for systems containing K2CO3 or K3PO4 were measured and correlated by Othmer-Tobias equation with satisfactory fitting performances (all R2 higher than 0.99). These results has ensured the reliability of these experimental data. The phase behaviors of these chiral MILATPs in this work has proved to meet the need of practical application and all these tested aqueous two-phase equilibrium data as well as the corresponding thermodynamic fitting can provide us useful reference for the future application in the field of extractive resolution of racemic amino acids.

Extraction of geniposidic acid and aucubin employing aqueous two-phase systems comprising ionic liquids and salts

Ionic liquid aqueous two-phase systems (ILATPS) exhibiting enhanced separation efficiency and selectivity have attracted enormous attention. In this study, diverse ILATPSs comprising 1-alkyl-3-methylimidazolium ([Cnmim]+) and inorganic salts were developed and studied for the extraction of geniposidic acid (GPA) and aucubin (AU) for the first time. The binodal curves were fitted to the nonlinear Merchuk relationship. The ability of these ILs to form ATPS increased as their alkyl side chains increased. Moreover, the performances of the utilized potential salts in the phase separation were compared. The influences of the types and amounts of ILs and salts, extraction temperature and time, and the amount of the initial mixed solution were investigated through single-factor experiments. Under the following optimum conditions: 25% (w/w) K2CO3, 30% (w/w) [Bmim]Br, 1.2 mL of the GPA and AU mixed solution, temperature of 10 °C and extraction time of 360 min, the maximum extraction efficiency (E1AU = 96.95%, E1GPA = 99.99%), partition coefficient (logKAU = 1.54 ± 0.01 and logKGPA = 4.47 ± 0.01), and S (843.57 ± 15.67) were obtained. Afterward, IL could be easily recycled without organic solvents via a metathesis reaction with lithium bis(trifluoromethane)sulfonamide (LiNTf2) during which hydrophilic [Bmim]Br could be converted into hydrophobic [Bmim]NTf2. Furthermore, the density functional theory (DFT) calculations revealed that the H-bond interactions were the main factor that affected this extraction; the H-bond between [Bmim]Br and GPA was stronger than that between [Bmim]Br and AU. This research is expected to avail meaningful theoretical references for the extraction of similar natural products from plants.

Extractive resolution of racemic phenylalanine and preparation of optically pure product by chiral magnetic ionic liquid aqueous two-phase system

In this report, chiral magnetic ionic liquid aqueous two-phase system was developed for the first time. Three novel chiral magnetic ionic liquids ([C2-4MIM-Tempo][L-Pro]) were synthesized and successfully used to construct aqueous two-phase system with inorganic salts (K2HPO4, K2CO3, K3PO4, Na2SO4, Na2CO3) for the extractive resolution of racemic phenylalanine. This novel system combined the advantages of organic solvent free, magnetic phase separation and rapid extraction together in an enantiomer resolution process for the first time. Phase behaviors and various influencing factors on resolution performance were systematically studied and optimized. The optimal extractive resolution conditions are: 1.4 g added water, 450 mg [C4MIM-Tempo][L-Pro], 100 mg Cu(OAc)2, 20 mg DL-Phe, 0.85 g K2HPO4, pH of added water as 7, system temperature as 298.15 K. Based on this, a novel preparation method of highly optically pure L-phenylalanine and D-phenylalanine was developed and achieved a satisfactory performance even in gram-scale. The e.e. value of L-phenylalanine in chiral MIL-rich phase reached 94.3% and the e.e. value of D-phenylalanine in salt-rich phase could reach 98.1%. Moreover, chiral magnetic ionic liquid could be recycled for at least 6 times with consistently good resolution ability. Hopefully, this green and recyclable resolution approach is showing great potential in industry.

Construction of an integrated platform for 5-HMF production and separation based on ionic liquid aqueous two-phase system

The research aims to develop a green and sustainable process for the production and extraction of 5-HMF from fructose using an aqueous two-phase system (ATPS) based on ionic liquid (IL). Because there is a large amount of research on the preparation of 5-HMF from fructose, there is no more effective way to separate them. It is very important to develop a method of selective separation, so the IL-based ATPS were studied and evaluated. The phase diagram of the novel IL-ATPS consisting of [C4mim][CF3SO3] and inorganic salts were determined. Different processing parameters, such as the concentration of inorganic salts and ionic liquids, the temperature and time of the separation system were investigated, optimize the process to maximize the separation of 5-HMF from the reaction system. The results showed that the ATPS of K3C6H5O7 and NaH2PO4 salts had the highest extraction efficiencies of 5-HMF and fructose in the two phases, which were 95.73 ± 0.26% and 97.27 ± 0.41%, 97.26 ± 0.10% and 95.51 ± 0.06%, respectively. The system was used to separate a variety of biomass-derived carbohydrates and 5-HMF, and it was found that a good separation effect was obtained, and the constructed system has broad applicability. The created production separation integrated platform is of great significance for getting high purity 5-HMF and fructose recycling.

Characterization of Ionic Liquid Aqueous Two-Phase Systems: Phase Separation Behaviors and the Hydrophobicity Index between the Two Phases.

1-Allyl-3-methylimidazolium chloride [Amim][Cl] and 1-butyl-3-methylimidazolium chloride [Bmim][Cl] are water-soluble ionic liquids (ILs) that can from an aqueous two-phase system (ATPS) when mixed with specific salts. Herein, we prepared [Amim][Cl]- and [Bmim][Cl]-ATPSs by adding the salts (K2CO3, K2HPO4). To investigate the phase separation behavior of the IL-ATPSs, binodal curves were drawn at different temperatures and the length and slope of the tie lines were analyzed. The [Bmim][Cl]/K2HPO4 system underwent two-phase separation at lower temperature conditions, suggesting that the phase separation might depend on the salting-out effect in the bottom phase. Using the IL-ATPS, the distribution coefficients, Kaa, of amino acids were determined and used to characterize the hydrophobicity index (HF) between the top and bottom phases, which is a good indicator to understand the molecular partitioning behaviors in conventional ATPSs. The HF values of the IL-ATPSs were in the range 0.13-0.41 mol/kJ; these values were almost the same as the HF values reported for an ATPS composed of poly(ethylene glycol) and salt.

The influence of temperature on the phase behavior of ionic liquid aqueous two-phase systems

In this article, the equilibrium behavior of solutions of 1-ethyl-3-methylimidazolium dimethyl phosphate ([Emim]DMP) and ethyl acetate or acetone in aqueous two-phase system (ATPS) was discussed to understand the liquid–liquid equilibrium (LLE) behavior of these organic solvents. Thus, we determined phase diagrams and LLE data at 303.15, 308.15, 313.15, and 323.15 K for the investigated biphasic systems. Four empirical equations were used to study the tie lines. The results showed that for the [Emim]DMP + acetone + water biphasic systems within the investigated temperature range, temperature influences the phase behavior, but for the [Emim]DMP + ethyl acetate + water biphasic systems within the investigated temperature range, there are no notable changes on the phase behavior with rising temperature. The results may have important applications for the separation of antibiotics and for the recovery of ionic liquids (ILs).

Optimization of [CnPy]Cl (n=2,4,6) ionic liquid aqueous two-phase system extraction of papain using response surface methodology with box-behnken design

Abstract This work used ionic liquid aqueous two-phase (ILATP) extraction technology to obtain high-purity and high-activity papain. Papain was extracted using [CnPy]Cl(n=2,4,6)-K2HPO4 ILATP systems. Response surface methodology (RSM) was developed to optimize the conditions. Firstly, the effects of the reagent, temperature and pH on papain activity were investigated. Secondly, the influences of the salt concentration, ionic liquid concentration, papain dosage, pH and temperature on the partition behaviour of papain were investigated. The overall desirability (OD) of the enzyme activity recovery and partition coefficient was response indicator. Furthermore, the absorption spectrum of papain before and after extraction was characterized by UV–vis absorption spectroscopy. Finally, the purity of papain extracted by ILATP was analysed by SDS-PAGE electrophoresis. The order of the effect of various factors on papain extraction was: K2HPO4 concentration, [C4Py]Cl concentration, pH and papain dosage. A high temperature is not conducive to the extraction of papain from an ILATP system. The extraction efficiency of the [C4Py]Cl-K2HPO4 system is superior to that of the [C2Py]Cl and [C6Py]Cl systems. The maximum OD value 0.8985 was obtained under the conditions of 0.35 g/mL K2HPO4, 0.25 g/mL [C4Py]Cl, pH of 7.87, papain dosage of 2.17 mg/mL at 30℃. The UV spectra of papain before and after extraction were the same. The specific activity of papain extracted by ILATP was 4120.17 U/mg, which was 1.88-fold the purity of commercial papain. This work provides theoretical guidance for optimized extraction process parameters and the preparation of high-activity enzymes.

Sorghum Bicolor L. leaf sheath polysaccharides: Dual frequency ultrasound-assisted extraction and desalination

Supramolecules extraction using single frequency ultrasound technology application has directional effect as a shortcoming. Thus, optimum disruption of materials for better yield is curtailed. One possible solution to this underperformance is the application of dual frequency ultrasound. Dual frequency ultrasound-assisted extraction (DF-UAE) of crude polysaccharide (SL-C80P) and ionic liquid aqueous two phase system (ILATPS) purified polysaccharide (SL-D10P) of sorghum (Sorghum bicolor L.) leaf sheath was achieved using response surface methodology (RSM). Experimental yield for crude and purified polysaccharide (14.10% and 97.17%) respectively was found to be very close to the predicted (14.88% and 97.40%). Higher desalination levels of (SL-D10P) was also observed after DF-UA dialysis. Surface morphology under scanning electron microscopy and molar ratios of monosaccharides composition of the two samples were different, but Fourier transform infrared spectroscopy was similar. Crude and purified polysaccharides were of helical structures as demonstrated by the congo red assay and recorded molecular weights (1,202,000 and 12,950 g/mol) respectively. The sample, (SL-D10P) displayed more elasticity whiles (SL-C80P) showed more viscosity in rheological terms. Finally, (SL-D10P) aggregated in water, detachable by heat and possessed a notable ABTS scavenging ability, thus remarkable potential for biomolecules protection. In conclusion, a better extraction yield of polysaccharides was achieved.

Ionic Liquid Aqueous Two-Phase Systems for the Enhanced Paper-Based Detection of Transferrin and Escherichia coli.

Aqueous two-phase systems (ATPSs) have been widely utilized for liquid-liquid extraction and purification of biomolecules, with some studies also demonstrating their capacity as a biomarker concentration technique for use in diagnostic settings. As the limited polarity range of conventional polymer-based ATPSs can restrict their use, ionic liquid (IL)-based ATPSs have been recently proposed as a promising alternative to polymer-based ATPSs, since ILs are regarded as tunable solvents with excellent solvation capabilities for a variety of natural compounds and proteins. This study demonstrates the first application of IL ATPSs to point-of-care diagnostics. ATPSs consisting of 1-butyl-3-methylimidazolium tetrafluoroborate ([Bmim][BF4]) and sodium phosphate salt were utilized to quickly concentrate biomarkers prior to detection using the lateral-flow immunoassay (LFA). We found the phase separation speed of the IL ATPS to be very rapid and a significant improvement upon the separation speed of both polymer-salt and micellar ATPSs. This system was successfully applied to both sandwich and competitive LFA formats and enhanced the detection of both Escherichia coli bacteria and the transferrin protein up to 8- and 20-fold, respectively. This system's compatibility with a broad range of biomolecules, rapid phase separation speed, and tunability suggest wide applicability for a large range of different antigens and biomarkers.

Temperature controlled ionic liquid aqueous two phase system combined with affinity capillary electrophoresis for rapid and precise pharmaceutical-protein binding measurements.

Temperature controlled ionic liquid aqueous two phase system (ILATPS) was used to improve the precision of pharmaceutical-AGP (human alpha (α1)-acid glycoprotein) binding measurements by affinity capillary electrophoresis (ACE). The effect of different types of short-chain alkyl imidazolium ILs within the concentration range of 10.0-1000.0 μmol L-1 on a propranolol (PRO)-AGP model was firstly investigated by ILATPS/ACE system. Use of 100.0 μmol L-1 1-butyl-3-methylimidazolium chloride (BMImCl) in 67.0 mmol L-1 potassium phosphate buffer (pH 7.4) containing low concentrations of AGP (5.0-100.0 µmol L-1) gave the highest precision value (2.98 ± 0.14 × 105 L/mol) which is in concord with the reported one (3.00 × 105) under similar experimental conditions. The proposed BMImCl/phosphate solution was a unique temperature controlled system to preserve AGP activity during the pre-analysis and within ACE measurements under lab conditions for about 30 days. This period could be prolonged by converting the one-phase solution into biphasic solution at 4 °C storage temperature and again it could get rapidly back into one-phase by raising the temperature with gentle shaking. This behavior could be attributed to the electrostatic interaction and π-π interaction between BMIm cations and negatively charged AGP ions (pI = 2.7). Moreover, the compatibility of ILATPS with ACE has been the critical factor to avoid precipitation of salts formed by anion exchange in the running buffer. The current ILATPS/ACE system was further used to rapidly and precisely estimate the binding constants of anticancer drugs methotrexate (MTX) and vinblastine (VBL) with human AGP. The obtained binding values have been in good agreements with their findings by high performance affinity chromatography (HPAC). This ILATP/ACE system could similarly be applied to improve the precision of other proteins binding measurements with consuming a small amount of protein and with shortening ACE analysis time.

Extraction in cholinium-based magnetic ionic liquid aqueous two-phase system for the determination of berberine hydrochloride in Rhizoma coptidis.

A magnetic ionic liquids (MILs)-based aqueous two-phase system (MIL-ATPs) obtained by mixing with a series of inorganic salts, which involves five cholinium MILs with the piperidinyloxy radical anion is reported for the first time. Phase diagrams for the new ATPs were experimentally determined at different temperatures (298.15–318.15 K) and the liquid–liquid equilibrium data for two-phase systems were correlated according to the empirical nonlinear expression. The effects of the types of MILs, temperature and inorganic salts on the binodal curve are discussed in detail. The MIL-ATPs coupled with HPLC-UV analysis was developed in the quantitation of berberine hydrochloride in Rhizoma coptidis. Under optimal conditions, the partition coefficient of berberine hydrochloride was 127.68 with the precision values (RSD%) of 1.40% and 2.83% for intra-day (n = 6) and inter-day (n = 3), respectively. The limit of detection (LOD) and limit of quantification (LOQ) for berberine hydrochloride were 0.023 mg L−1 and 0.077 mg L−1, respectively. The recoveries were obtained in the acceptable range of 97.4–101.2%. Moreover, the content of berberine hydrochloride in the raw material of Rhizoma coptidis was measured as 123.95 mg g−1 with this method. Finally, 99.8% MIL was recovered for cycle application after the removal of berberine hydrochloride by using D101 resin. This study provides a meaningful reference for the application of MIL-ATPs with great prospects.

Recovery and primary purification of bacteriophage M13 using aqueous two‐phase systems

AbstractBACKGROUNDBacteriophage M13 is an Escherichia coli‐specific non‐lytic filamentous virus commonly used in applications ranging from antibody screening and nanomaterial construction to drug delivery, among others. In this tenor, alternative methods for the fractionation, recovery and partial purification of phage particles are desired. In this work, the use of aqueous two‐phase systems (ATPS) was evaluated as an alternative method for the recovery of phage particles.RESULTSThe partition behavior of M13 in PEG–salt and ionic liquid (IL)–salt ATPS was characterized using a pre‐purified feedstock. In PEG‐salt ATPS, M13 was preferentially partitioned to the interface. In IL ATPS, however, M13 showed a high‐top phase preference with recovery yields above 65%. Selected systems were tested for the extraction of M13 from a crude fermentation broth. From crude broth, a PEG 400‐potassium phosphate system with volume ratio (VR) of 1 and 25% w/w tie line length (TLL) gave the best M13 top phase recovery (83%) and purification fold (18.2) in terms of total protein concentration.CONCLUSIONSThe results presented here demonstrate the practical application of ATPS as an efficient process for the primary recovery and partial purification of M13 and represent the first study of the extraction of viral particles directly from a crude broth as well as the use of IL‐Salt ATPS. © 2017 Society of Chemical Industry