Single Solvent System Research Articles

Extraction of curcumin from turmeric rhizome utilized by a surfactant-free microemulsion based on deep eutectic solvent

This study aimed to develop a surfactant-free microemulsion (SFME) which based on hydrophobic deep eutectic solvent (DES), intended to prospect its extraction effect of curcuminoids. A menthol and n-octanoic acid (ME-OA 1:2) hydrophobic DES is used as oil phase to SFME which have low viscosity, higher stability and better solubility for extracting curcuminoids. The hydrophobic DES was successfully formed which was demonstrated by 1HNMR and FT-IR. The ternary phase diagram and the microstructure of microemulsions was determined via visual titration, light scattering experiment and electrical conductivity. SFME consisting of ME-OA/Ethanol/H2O (1/7/2 mass ratio) had been constructed to investigate its ability to extract curcuminoids from turmeric rhizome utilizing HPLC. And the it was tested the extracted curcuminoids as a function of extraction time by UV–vis spectra. Using the single-factor experiments and response surface methodology (RSM), the optimal extraction conditions by ultrasound-assisted SFME were identified as follows: liquid/solid ratio of 12 g/g, extraction time of 63 min, and ultrasonic time (300 W) of 45 min. The total extraction amounts of curcuminoids could reach 61.39 mg/g powder under the best conditions, and the main factor to influence the final extraction effect was extraction time. The molecular dynamic simulation was performed to investigate the interaction between SFME and curcuminoids. Compared with the single component solvent system of ethanol, acetone, ME-OA and water, curcuminoids were stronger interaction energy with solvent molecules and higher hydrogen bond number in SFME. SFME formed the O/W structure of encapsulation solubilization for curcuminoids, in order to promote the dissolving of curcuminoids.

Solubility evaluation of palm-based Mono-diacylglycerols (MDAGs) in food grade solvent (hexane, ethanol, acetone, water) using QSPR model approach

Mono-diacylglycerols (MDAGs) are emulsifiers widely used in the food industry. MDAGs based on refined bleached deodorized palm stearin (RBDPS) have not been widely developed. MDAGs have been synthesized using glicerolysis between RBDPS and glycerols. Due to their low solubility in food-grade solvents (hexane, ethanol, acetone, and water), it has been difficult to purify or fractionate MDAGs only by a simple method. This research attempted to develop a model of MDAGs solubility in food-grade solvents and understand the parameters that influence the solubility of MDAGs in food-grade solvents. The process used a combination of experimental data collection and quantitative structure–property relationship (QSPR) models. The QSPR model for MDAGs solubility in a single and binary solvent demonstrated that the descriptors of Δ dipole moment (Δµ), E HOMO, E LUMO, electronic energy, gap energy HOMO-LUMO (ΔE1, ΔE2) softness (S), electrophilicity index (ω), and electron transfer (ΔN) have a significant impact in determining the solubility of MDAGs. Both the single and the binary solvents solubility models can give satisfactory prediction results: the square of the correlation coefficient (R2pred) was 0.933 and 0.948, and the root-mean-square error (RMSE) was 0.075 and 0.031, respectively, for the whole data set. In addition, this paper provided a new and effective method for predicting the solubility of MDAGs in single and binary food-grade solvent systems.

Effects of Assisting Solvents on Purification Efficiency in the Layer Melt Crystallization of Glycerol.

The efficiency of layer melt crystallization for the selective separation of glycerol from a glycerol-diethylene glycol mixture containing 4 wt % of diethylene glycol was evaluated using solvent-free and solvent-aided approaches. The effect of 1-butanol and the binary solvent of 1-butanol and acetone with a total molar composition of 25 mol % on the crystal growth kinetics and the purity of the final product was studied at different undercooling degrees and crystallization yields. The melting point temperature of the mixtures was predicted by using the modified UNIFAC Dortmund model. The addition of both a single and binary solvents significantly increased the crystal growth rate and purity of the final product compared to crystallization from the solvent-free mixture. Additionally, higher crystal growth rates and product purity were observed in the binary solvent system compared to those in the single solvent system at the same degree of undercooling. The second stage of solvent-aided crystallization resulted in glycerol with a purity above 99.5 wt %, depending on the type of solvent used and the rate of crystal growth.

Strong Anionic/Charge-Neutral Block Copolymers from Cu(0)-Mediated Reversible Deactivation Radical Polymerization.

Despite recent developments in controlled polymerization techniques, the straightforward synthesis of block copolymers that feature both strong anionic and charge-neutral segments remains a difficult endeavor. In particular, solubility issues may arise during the direct synthesis of strong amphiphiles and typical postpolymerization deprotection often requires harsh conditions. To overcome these challenges, we employed Cu(0)-mediated reversible deactivation radical polymerization (Cu(0)-RDRP) on a hydrophobic isobutoxy-protected 3-sulfopropyl acrylate. Cu(0)-RDRP enables the rapid synthesis of the polymer, reaching high conversions and low dispersities while using a single solvent system and low amounts of copper species. These macromolecules are straightforward to characterize and can subsequently be deprotected in a mild yet highly efficient fashion to expose their strongly charged nature. Furthermore, a protected sulfonate segment could be grown from a variety of charge-neutral macroinitiators to produce, after the use of the same deprotection chemistry, a library of amphiphilic, double-hydrophilic as well as thermoresponsive block copolymers (BCPs). The ability of these various BCPs to self-assemble in aqueous media was further studied by dynamic light scattering, ζ-potential measurements as well as atomic force and electron microscopy.

Design of spherical agglomerates via crystallization with a non-toxic bridging liquid: From mechanism to application

The cooling crystallization-spherical agglomeration (CCSA) technology proposed in this work overcomes the disadvantages of complex process and biohazardous solvents, which has broad application prospects in green and efficient granulation. CCSA selects oleic acid as a novel green and effective bridging liquid, and the results of droplet experiment and molecular simulation indicate that oleic acid presents the best wetting performance compared with the reported bridging liquids. Mechanistic studies demonstrate that oleic acid can induce spherical agglomeration during crystallization in a single solvent system, especially in water, reducing the dosage of organic solvent by about 90%, and fundamentally eliminating the toxicity of bridging liquid. The volume ratio of bridging liquid to solvent (RBS) and agitation are emphasized as the critical parameters tuning the particle size and sphericity. Further, the spherical agglomerates of benzoic acid, L-leucine and aspirin with controllable size and high sphericity were successfully prepared, which verifies the universality of CCSA.

Validation, Optimization and Hepatoprotective Effects of Boeravinone B and Caffeic Acid Compounds from Boerhavia diffusa Linn

Boerhavia diffusa, also known as Punarnava, is a plant of the Nyctaginaceae family that has been utilized in traditional medicine to cure a variety of ailments. The goal of this study was to use response surface methodology (RSM) to optimize the maximum percentage yield of boeravinone B and caffeic acid from Boerhavia diffusa roots, and simultaneous determination of boeravinone B and caffeic acid in newly developed single solvent system and demonstrate the hepatoprotective benefits of boeravinone B and caffeic acid. The extraction process examined extraction time, extraction temperature and solvent concentration, which were optimized via Box–Behnken experimental design. The proposed HPTLC method for the quantification of boeravinone B and caffeic acid were successfully validated and developed. The method was validated in term of linearity and detection limit, quantification limit, range, precision, specificity and accuracy. The separation of boeravinone B and caffeic acid bands was achieved on HPTLC plate using formic acid: ethyl acetate: toluene (1:3:5 v/v) as developing system. Densitometric analyses of boeravinone B and caffeic acid was carried out in the absorbance mode at 254 nm. The maximum percentage yield of caffeic acid and boeravinone B from Boerhavia diffusa require appropriate extraction parameters such as temperature, time, organic solvents and water content, which can be achieved using the Box-Behnken statistical design provide time: temperature: solvent ratio (30:45:40 v/v) for extraction of caffeic acid and 60:60:40 v/v for extraction of boeravinone B. The boeravinone B (200 µg/mL) and caffeic acid (200 µg/mL) showed the most significant hepatoprotective activity compared with standard sylimarin in HepG2 cell induced with galactosamine 40 mM toxicity. The findings supported B. diffusa’s traditional use as a functional food forhuman health benefits.

Sustainable, highly selective, and metal-free thermal depolymerization of poly-(3-hydroxybutyrate) to crotonic acid in recoverable ionic liquids

Highly selective and metal free synthesis of industrially important crotonic acid is accomplished by using a single and recoverable solvent system under mild reaction conditions.

Densitometric Quantification and Optimization of Polyphenols in Phyllanthus maderaspatensis by HPTLC

Quantifying and optimizing the polyphenol content of Phyllanthus maderaspatensis was accomplished using a single-solvent HPTLC system. Analyzing hydroalcoholic extracts for kaempferol, rutin, ellagic acid, quercetin, catechin, and gallic acid, we simultaneously quantified and optimized their concentration. In the experiment, the methanol to water ratio (%), temperature (°C), and time of extraction (min) were all optimized using a Box-Behnken statistical design. Kaempferol, rutin, ellagic acid, quercetin, catechin, and gallic acid were among the dependent variables analyzed. In the HPTLC separation, silica gel 60F254 plates were used, and toluene, ethyl acetate, and formic acid (5:4:1) made up the mobile phase. For kaempferol, rutin, ellagic acid, quercetin, catechin, and gallic acid, densitometric measurements were carried out using the absorbance mode at 254 nm. Hydroalcoholic extract of P. maderaspatensis contains rutin (0.344), catechin (2.62), gallic acid (0.93), ellagic acid (0.172), quercetin (0.0108) and kaempferol (0.06). Further, it may be affected by more than one factor at a time, resulting in a varying degree of reaction. A negative correlation was found between X1 (extraction time (min)) and X2 (temperature), as well as X1 and X3 (solvent ratios). Taking these characteristics into consideration, the method outlined here is a validated HPTLC method for measuring kaempferol, rutin, ellagic acid, quercetin, catechin, and gallic acid.

Superior long-term cycling of high-voltage lithium-ion batteries enabled by single-solvent electrolyte

A new single-solvent electrolyte system comprising lithium bis(fluorosuflonyl) imide (LiFSI) and β -fluorinated sulfone (TFPMS) was designed to enable very stable long-term cycling of high-voltage lithium-ion batteries. Compared to other fluorinated solvents such as α -fluorinated sulfone (FMES) and fluorinated carbonate (FEMC), which are prone to reduction on the graphite anode, the LiFSI-TFPMS system displayed outstanding compatibility with graphite. While regular carbonate and sulfone from the LiFSI electrolyte system are compatible with the graphite anode, their high solvating power not only induces severe corrosion on the aluminum cathode current collector at high voltage, but also renders a low aggregation level at a normal salt concentration (about 1.0 M), resulting in the formation of an unstable solid-electrolyte interphase (SEI) on the graphite anode. Owing to the low solvating power of TFPMS, the aggregation level of the LiFSI-TFPMS system is relatively high even at normal salt concentration, which not only facilitates the formation of a robust SEI by the sacrificial decomposition of LiFSI, but also suppresses the aluminum corrosion of the LiFSI electrolyte system at high voltage. Together with the high intrinsic anodic stability of TFPMS, the superior cycling performance of graphite||LiNi 0.6 Co 0.2 Mn 0.2 O 2 cells was achieved by employing the non-flammable LiFSI-TFPMS single-solvent electrolyte system. • Introduce a new single-solvent electrolyte system comprising LiFSI and TFPMS for very stable cycling of high-voltage LIBs. • Unlike α -fluorinated sulfone, LiFSI-TFPMS system at normal salt concentration is compatible with the graphite anode. • The LiFSI-TFPMS electrolyte enables the formation of a robust SEI by the sacrificial decomposition of LiFSI. • The LiFSI-TFPMS system outperformed many reported electrolytes for high-voltage lithium-ion system.

Particle design of the metastable form of clopidogrel hydrogen sulfate by building spherulitic growth operating spaces in binary solvent systems

Clopidogrel hydrogen sulfate occupies a large market share of antithrombotic drugs. Its metastable form I has the advantages of high solubility and bioavailability. However, the poor powder properties and stability limit its application. This work solved the issue by building spherulitic growth operating space in “isopropyl acetate + lower alcohol” binary solvent systems. The systems were selected by the indicators of solubility and isosteric adsorption heats. By investigating crystal morphologies, polymorph transformation, and gelation with supersaturation gradient experiment, ATR-FTIR spectroscopy, and inverted tube method, these binary solvent systems follow the supersaturation-dependent spherulitic growth mechanism providing operating spaces significantly larger than the reported single solvent system. Hence, an optimal crystallization process was designed to prepare high-quality spherulites of form I avoiding polymorph transformation and gelation. Compared with the reported single solvent system, the optimized product presents better powder properties with residual solvent decreased by 59% and operating time decreased by 75%–90%.

TUNING SURFACE ROUGHNESS OF ELECTROSPUN POLY CAPROLACTONE FIBRES BY SINGLE SOLVENT ELECTROSPINNING SYSTEM

Secondary surface texture or surface roughness is having a powerful impact on morphological variety and magnifies the application areas of electrospun fibres. This paper for the first time assesses the formation of varying degrees of surface pores on electrospun poly caprolactone (PCL) fibres by using a single solvent system. PCL solutions were prepared by dissolving PCL granules in dichloromethane (DCM) at the concentration of 5, 10, 15 and 20% (w/v), before being subjected to the electrospinning process at lower kV values of 5, 10 and 15, respectively. The morphology of electrospun fibres was characterised by field emission scanning electron microscope (FESEM). The resultant PCL fibres showed a highly porous surface was formed at lower PCL concentration. The surface roughness of PCL fibres was increased gradually with the increment of PCL concentration. The formation of porous surface was mainly due to the fast phase separation process while pore size and pore size distribution was found to depend on the blend composition.

Influence of Coagulation Bath Temperature on the Structure and Dielectric Properties of Porous Polyimide Films in Different Solvent Systems.

In this work, the effect of coagulation bath temperature in different solvent systems [1,4-butyrolactone (GBL)/N,N-dimethylacetamide (DMAC)] on the structure and dielectric properties of polyimide (PI) films was investigated for the first time. The solubility parameter was introduced to explain the formation process of porous PI films. The results showed that the changed tendency of the dielectric constant versus temperature is opposite for the single-solvent system and cosolvent system. For a single DMAC and GBL solvent, the dielectric constants of the films decreased with increasing temperature. In contrast, the dielectric constants increased with the increase in temperature for the GBL/DMAC cosolvent system. Moreover, the measured porosities were applied to estimate the dielectric constants of the PI films. This showed that the porosity increased with increasing temperature for a single-solvent system, while it decreased for a cosolvent system. Scanning electron microscopy images suggested that the variation trends are derived from the different influences of the temperature on the structure and morphology. Thus, this study reveals the effect of coagulation bath temperature on the structure and dielectric properties of porous PI films and provides the guidance for the design and optimization of architectures for high-performance porous films.

Cosolvent Effects When Blade-Coating a Low-Solubility Conjugated Polymer for Bulk Heterojunction Organic Photovoltaics.

The adoption of solution-processed active layers in the production of thin-film photovoltaics is hampered by the transition from research fabrication techniques to scalable processing. We report a detailed study of the role of processing in determining the morphology and performance of organic photovoltaic devices using a commercially available, low-solubility, high-molar mass diketopyrrolopyrrole-based polymer donor. Ambient blade coating of thick layers in an inverted architecture was performed to best model scalable processing. Device performance was strongly dependent on the introduction of either o-dichlorobenzene (DCB), 1,8-diiodooctane, or diphenyl ether cosolvent into the chloroform (CHCl3) solution, which were all shown to drastically improve the morphology. To understand the origin of these morphological changes as a result of the addition of the cosolvent, in situ studies with grazing-incidence X-ray scattering and optical reflection interferometry were performed. Use of any of the cosolvents decreases the domain size relative to the single solvent system and moved the drying mechanism away from what is likely liquid-liquid phase separation to solid-liquid phase separation driven by polymer aggregation. Comparing the CHCl3 + DCB cast films to the CHCl3-only cast films, we observed both the formation of small domains and an increase in crystallinity during the evaporation of DCB due to a high nucleation rate from supersaturation. This resulted in percolated bulk heterojunction networks that performed similarly well with a wide range of film thicknesses from 180 to 440 nm, making this system amenable to continuous roll-to-roll processing methods.

Roll-to-roll slot-die coated P–I–N perovskite solar cells using acetonitrile based single step perovskite solvent system

Roll-to-roll coating of all active layers is demonstrated for a P–I–N perovskite solar cell stack, using a single step perovskite ink with an acetonitrile solvent system and flexible plastic substrate.

Evaluation of CO2-induced azole-based switchable ionic liquid with hydrophobic/hydrophilic reversible transition as single solvent system for coupling lipid extraction and separation from wet microalgae

The utilization of microalgae as bioenergy source was limited by the excessive cost and energy consumption during the process of lipid extraction and separation. CO2-induced switchable ionic liquids (S-ILs) with reversible hydrophobic-hydrophilic conversion were synthesized and applied for lipid extraction and separation. The reversible transition mechanism of switchable IL is due to the formation of carbamate. The novel approach based on S-ILs was developed for lipid extraction from wet microalgae, which coupled microalgae cell disruption, lipid extraction, separation, and solvent recovery process without additional solvents. The highest lipid extraction efficiencies from wet microalgae were obtained by C6DIPA-Im, and the lipids were recovered from the extraction phase by simply bubbling CO2. Furthermore, C6DIPA-Im maintained more than 83.6 ± 3.6% of its initial lipid extraction efficiency after recycling five times. The S-IL based extraction and separation method provides a new strategy for sustainable bioenergy production.

Synthesis of vitamin E succinate catalyzed by nano-SiO2 immobilized DMAP derivative in mixed solvent system

Abstract Catalytic efficiency in synthesis of vitamin E succinate was dramatically increased via the preparation of robust catalyst and the improvement of reaction system. 4-dimethylaminopyridine (DMAP) was covalently immobilized on nano-SiO2 to avoid the catalyst contamination of the product and permit the easy recycling of DMAP. Then, a hexane-acetone mixed solvent system was firstly introduced to replace the traditional single-solvent system, which was employed to improve the activity of immobilized DMAP derivative and the substrate solubility of the reaction system. The highest vitamin E succinate yield of 94% was achieved. In addition, the recyclability and stability of the immobilized DMAP derivative was excellent, the yield of vitamin E succinate had no obvious loss and remained 90% after recycling 20 times. The excellent results make this technology be a promising candidate for the industrial production of vitamin E succinate.

A simple method for extracting both active oily and water soluble extract (WSE) from Nigella sativa (L.) seeds using a single solvent system

The current study provides a way of extraction for both active NSO and WSE from Nigella sativa seeds using 98% methanol. About 1 kg of ground seeds was macerated by 1:2.5 w/v (g/mL) for 72 hours. After rotary evaporation and 7 days of continuous drying and chilling at 50 and 4 °C, NSO and WSE were obtained at the same instant. Solubility tests of 24 solvents and 11 thin layer chromatographic analyses while 2, 2-diphenyl-1-picrylhydrazyl free radical scavenging assay of NSO (73.66) , WSE (33.32) and NSO + WSE (78.22) against ascorbic acid (IC50 = 4.28 mg/mL) was performed. WSE was found to be highly soluble in water and 5% NaOH exhibiting the same Rf value of 0.95 for EtOH:DMSO (9:1) against the honey. WSE has revealed more than twofold higher anti-oxidant activity than others. Formulation of WSE with Tualang honey may provide better targeted hydrophilic drug delivery systems.

Enhanced Photovoltaic Performance of FASnI3-Based Perovskite Solar Cells with Hydrazinium Chloride Coadditive

For the fabrication of efficient Sn-based perovskite solar cells (PSCs), deposition of uniform and pinhole-free perovskite films with low Sn4+ content remains a crucial factor. In this work, we present a coadditive engineering process by introduction of hydrazinium chloride (N2H5Cl) in a single precursor solvent system to fabricate FASnI3 perovskite films. The successful integration of N2H5Cl results in reduced concentration of Sn4+ content by 20% in the FASnI3 film leading to suppressed carrier recombination and pinhole-free uniform coverage. These remarkable improvements in the FASnI3 film results in power conversion efficiency (PCE) of Sn-based PSC up to 5.4% due to a significant increase in open-circuit voltage. Moreover, the best PSC without encapsulation showed stable shelf life up to 1000 h while retaining 65% of its initial PCE.

Enhanced Photovoltaic Performance of Perovskite Solar Cells by Copper Chloride (CuCl2) as an Additive in Single Solvent Perovskite Precursor

In this letter, we have introduced copper chloride (CuCl2) as an additive in the CH3NH3PbI3 precursor solution to improve the surface morphology and crystallinity of CH3NH3PbI3 films in a single solvent system. Our optimized perovskite solar cells (PSCs) with 2.5 mol% CuCl2 additive showed best power conversion efficiency (PCE) of 15.22%. The PCE of the PSCs fabricated by CuCl2 (2.5 mol%) additive engineering was 56% higher than the PSC fabricated with pristine CH3NH3PbI3.

Application of linear gradient elution in countercurrent chromatography for the separation of triterpenoid saponins from the roots of Pulsatilla koreana Nakai.

A linear gradient elution method using countercurrent chromatography was developed for the separation of four triterpenoid saponins from the roots of Pulsatilla koreana Nakai, including hederacolchiside E, which is responsible for the neuroprotective activity of this plant. The target fraction was obtained by 80% methanol elution of solid phase column chromatography. The partition coefficients of the target compounds were very different, which means they are difficult to separate with a single biphasic solvent system. Several important parameters for gradient elution, such as addition of alcohol content to the solvent system, starting point of the second mobile phase, and the time for the gradient change were logically determined and optimized. Four triterpenoid saponins could ultimately be separated, analyzed by high-performance liquid chromatography, and their structures were identified by comparing the mass spectra and NMR spectra with the literature data. The compounds and yields were: hederasaponin B (1; 21.3mg/100mg), hederacolchiside E (2; 19.8mg/100mg), cernuoside A (3; 18.4mg/100mg), and cernuoside B (4; 17.3mg/100mg). Gradient-elution countercurrent chromatography allows the effective separation of compounds with a wide polarity range.