Nonpolar Organic Solvents Research Articles

Direct patterning of liquid materials on flat and curved substrates using flexible molds with through-hole and post arrays.

Liquids undergo continuous deformation in the presence of external shear stresses; however, they are pinned between structures owing to their viscosity. Therefore, reshaping the liquids using their intrinsic material properties and structural interfaces is possible. In this study, we used the template-guided forming (TGF) method to reshape and produce oil patterns on flat and curved substrates. To produce oil patterns, we developed two oil patterning methods: direct heating-based oil patterning (DHOP) and solvent evaporation-based oil patterning (SEOP), which were characterized using various oils and solvents. To overcome the limitation of relying solely on liquid patterning that undergoes complete evaporation, we successfully fabricated liquid films using oil and nonpolar organic solvents that exhibit long-term stability. Therefore, achieving durability and control over the film thickness using nonpolar organic solvents has great potential for future applications in microfluidics. Furthermore, we demonstrated that the SEOP method in conjunction with TGF can produce various and unconventional patterns of an organic photoresist (SU-8), which cannot be produced through standard photolithography. Hence, we conclude that the proposed TFG-based oil pattering methods could be highly useful for producing unconventional and unprecedented patterns on flat and curved substrates for various applications, including microelectronics, optics, filtration and separation, biomedical engineering, and nanotechnology.

Forceless spontaneous delamination of high-aspect ratio fluorohectorite into monolayer nanosheets in chloroform.

One-dimensional dissolution of a layered compound in a nonpolar organic solvent is reported for the first time. A high-aspect ratio fluorohectorite modified with a cationic surfactant (dioctadecyldimethylammonium) showed spontaneous delamination into monolayer nanosheets in chloroform.

Ultralight aerogels via supramolecular polymerization of a new chiral perfluoropyridine-based sulfonimidamide organogelator.

Chiral and enantiopure perfluorinated sulfonimidamides act as low-molecular weight gelators at low critical gelation concentration (<1 mg mL-1) via supramolecular polymerization in nonpolar organic solvents and more heterogenic mixtures, such as biodiesel and oil. Freeze-drying of the organogel leads to ultralight aerogel with extremely low density (1 mg mL-1). The gelation is driven by hydrogen bonding resulting in a helical molecular ordering and unique fibre assemblies as confirmed by scanning electron microscopy, CD spectroscopy, and computational modeling of the supramolecular structure.

Investigating the efficacy of green solvents and solvent-free conditions in hydrogen-bonding mediated organocatalyzed model reactions.

In this study, we have delved into various reactions conducted using green solvents or under solvent-free conditions, employing hydrogen bonding organocatalysis to advance more sustainable practices in chemical synthesis. The outcomes suggest that cyclopentyl methyl ether could potentially replace non-polar organic solvents such as hexane and toluene with comparable enantioselectivity and yields. The non-polar nature of liquefied or supercritical CO2 restricts its application to reactions that require non-polar solvents. Furthermore, pursuing solvent-free conditions, even without liquid substrates, might result in similar conversion rates with reduced catalyst loading. These findings highlight the potential of exploring solvent-free conditions when enantioselectivity is not of concern. Based on the results, solvent-free conditions and bio-based solvents can serve as viable alternatives to conventional organic solvents without compromising performance. This is expected to influence the way chemists approach reaction optimisation within method development in the field, fostering a broader adoption of environmentally friendly approaches.

Volatile compounds in Trigona honey and their potential as antimicrobials

Indonesia is rich in natural resources, one of which is honey, which needs to be developed to improve quality and have competitiveness. This study aimed to determine the volatile compounds in Trigona honey and their potential as antimicrobials. This research was carried out in four stages, namely the sample preparation stage, the extraction stage, the volatile compound identification stage, and the determination of volatile antimicrobial compounds stage. Trigona honey samples were obtained from Masamba, South Sulawesi. The extraction was carried out in the chemical laboratory of the Faculty of Chemistry, Hasanuddin University. Honey was extracted with two non-polar (n-hexane) and semipolar (ethyl acetate) organic solvents. Adjustment of volatile compounds extracted using Gas chromatography-mass spectrometry (GC-MS) was carried out at the The State Police of the Republic of Indonesia (POLRI) Forensic Laboratory. A total of twenty-seven volatile organic compounds including carbonates, acids, aldehydes, ketones, alcohols, phenolics, amines, imines and oximes were detected in the Trigona honey. Of the twentyseven volatile compounds found in Trigona honey, there were six compounds that have potential as antimicrobials namely heptadecane, benzoic acids 1,3 dioxolane, eicosane, 3- hydroxy-4-methoxybenzaldehyde and phenolic compounds.

Stepwise Functionalization of a Pillar[5]arene-Containing [2]Rotaxane with Pentafluorophenyl Ester Stoppers.

Detailed investigations into the stepwise bis-functionalization of a pillar[5]arene-containing rotaxane building block have been carried out. Upon a first stopper exchange, the pillar[5]arene moiety of the mono-acylated product is preferentially located close to its reactive pentafluorophenyl ester stopper, thus limiting the accessibility to the reactive carbonyl group by the nucleophilic reagents. Selective mono-functionalization is thus very efficient. Introduction of a second stopper is then possible to generate dissymmetrical rotaxanes with different amide stoppers. Moreover, when dethreading is possible upon the second acylation, the pillar[5]arene plays the role of a protecting group allowing the synthesis of dissymmetrical axles that are particularly difficult to prepare under statistical conditions. Finally, detailed conformation analysis of the rotaxanes revealed that the position of the pillar[5]arene moiety on its axle subunit is mainly governed by polar interactions in nonpolar organic solvents, whereas solvophobic effects play a major role in polar solvents.

Impact of lipid matrix composition on the activity of membranotropic enzymes galactonolactone oxidase from Trypanosoma cruzi and L-galactono-1,4-lactone dehydrogenase from &lt;i&gt;Arabidopsis thaliana&lt;/i&gt; in the system of reverse micelles

The study of many membrane enzymes in an aqueous medium is difficult due to the loss of their catalytic activity, which makes it necessary to use membrane-like systems, such as reverse micelles of surfactants in nonpolar organic solvents. However, it should be taken into account that micelles are a simplified model of natural membranes, since membranes contain many different components, a significant part of which are phospholipids. In this work, we studied the impact of the main phospholipids, phosphatidylcholine (PC) and phosphatidylethanolamine (PE), on the activity of membrane enzymes using galactonolactone oxidase from Trypanosoma cruzi (TcGAL) and L-galactono-1,4-lactone dehydrogenase from Arabidopsis thaliana (AtGALDH) as an examples. Effect of the structure (and charge) of the micelle-forming surfactant itself on the activity of both enzymes has been studied using an anionic surfactant (AOT), a neutral surfactant (Bridge-96), and a mixture of cationic and anionic surfactants (CTAB and AOT) as an examples. The pronounced effect of addition of PC and PE lipids on the activity of AtGALDH and TcGAL has been detected, which manifests as increase in catalytic activity and significant change in the activity profile. This can be explained by formation of the tetrameric form of enzymes and/or protein-lipid complexes. By varying composition and structure of the micelle-forming surfactants (AOT, CTAB, and Brijdge-96 and their combinations) it has been possible to change catalytic properties of the enzyme due to effect of the surfactant on the micelle size, lipid mobility, charge, and rigidity of the matrix itself.

Application of the liquid-liquid extraction method and subsequent icp-ms detection for speciation analysis of arsenic in wastewater samples

The current paper describes a method for determining As(III) and As(V) concentrations in wastewater samples. The approach is based on the extraction of As(III) from water samples using a non-polar organic solvent in a 10-12 M HCl medium. The extract contains As(III), while the raffinate contains As(V). Distilled water can be used to re-extract As(III) from the organic solvent. ICP-MS was used to analyze As concentrations in the reextract and the raffinate. The average recovery of arsenic by the proposed method is 99.6 %. It was calculated as the sum of As(III) and As(V) concentrations. The collected data demonstrated high repeatability. The standard addition procedure demonstrated the selectivity and accuracy of the employed method. The relative error of recovery of the standard As(III) addition is about 2 %, which is similar to the RSD found under repeatability conditions.

Precise and ultra-wide molecular sieving capability with size-dependent COF layers for fast organic solvent nanofiltration

Four covalent organic framework (COF) layers with different alkyl side chains are used to create thin film composite (TFC) membranes via the improved unidirectional diffusion synthetic (UDS) technique. The synthesized membranes consist of polyacrylonitrile (PAN) substrates and TAPB-TPOCx COF (x = 1, 4, 6, and 8) layers, whose pore size and pore environment are tuned by direct integration of variable-length of TPOCx monomers. For organic solvent nanofiltration (OSN), we apply these COF membranes with variable thickness and pore size to test for the sieving ability of various organic pollutant surrogates. With the COF layers' bi-variable thickness and substituent length, the range cut-off molecular weight (330–970 g mol−1) for TAPB-TPOCx COF membranes involves the vast majority of OSN molecular sieving ranges. The COF membranes demonstrate precise molecular sieving capability with higher permeance of polar and nonpolar organic solvents than the state-of-the-art polymeric membranes.

Impact of Lipid Matrix Composition on Activity of Membranotropic Enzymes Galactonolactone Oxidase from Trypanosoma cruzi and L-Galactono-1,4-Lactone Dehydrogenase from Arabidopsis thaliana in the System of Reverse Micelles.

The study of many membrane enzymes in an aqueous medium is difficult due to the loss of their catalytic activity, which makes it necessary to use membrane-like systems, such as reverse micelles of surfactants in nonpolar organic solvents. However, it should be taken into account that the micelles are a simplified model of natural membranes, since membranes contain many different components, a significant part of which are phospholipids. In this work, we studied impact of the main phospholipids, phosphatidylcholine (PC) and phosphatidylethanolamine (PE), on activity of the membrane enzymes using galactonolactone oxidase from Trypanosoma cruzi (TcGAL) and L-galactono-1,4-lactone dehydrogenase from Arabidopsis thaliana (AtGALDH) as examples. Effect of the structure (and charge) of the micelle-forming surfactant itself on the activity of both enzymes has been studied using an anionic surfactant (AOT), a neutral surfactant (Brij-96), and a mixture of cationic and anionic surfactants (CTAB and AOT) as examples. The pronounced effect of addition of PC and PE lipids on the activity of AtGALDH and TcGAL has been detected, which manifests as increase in catalytic activity and significant change in the activity profile. This can be explained by formation of the tetrameric form of enzymes and/or protein-lipid complexes. By varying composition and structure of the micelle-forming surfactants (AOT, CTAB, and Brij-96) it has been possible to change catalytic properties of the enzyme due to effect of the surfactant on the micelle size, lipid mobility, charge, and rigidity of the matrix itself.

Fabrication of high‐performance poly(vinyl alcohol) tubes via stable melt extrusion by reversible crosslinking of boric acid

AbstractThe unique intermolecular interactions of poly(vinyl alcohol) (PVA) endow it with excellent barrier properties to oxygen and nonpolar hydrocarbon organic solvents, thus having potential applications in the fields of oil and gas transmission. In view of the difficulties in thermal processing of PVA and based on the molecular complexation technology established by our research group, the melt extrusion of PVA tubes was achieved. To improve the extrusion stability of PVA tubes, boric acid (BA), which could form reversible crosslinking with PVA, was further introduced, and the influences of BA content on the interactions between BA and PVA, the thermal processability of PVA, as well as the mechanical properties and gasoline barrier properties of PVA tubes were systematically studied. The results showed that BA could form both chemical and physical crosslinking with PVA, so controlled the violent evaporation of water, one of plasticizers with low boiling point, and at the same time ensured the good thermal processing of PVA, lastly realizing the stable melt extrusion of PVA tubes. With the increase of BA content, the crystallinity of PVA decreased, but the glass transition temperature, mechanical properties, thermal dimensional stability, as well as water resistance of PVA tubes increased. The gasoline barrier of PVA tubes reached the best at the BA content of 0.10 wt%, that is, 0.97 g mm/m2 day.

Novel amino-beta cyclodextrin-based organic solvent nanofiltration membranes with fast and stable solvent transport

To expand industrial utilizations, membranes with fast transport of organic solvents and precision molecular separation, along with strong chemical stability, have great potential for minimizing energy consumption in separation processes. In this study, novel amino-cyclodextrin organic solvent nanofiltration (OSN) membranes containing P84 polymer were successfully fabricated using amino-cyclodextrin and amino-5-guanidinopentanoic acid (DL-A) as monomers through a two-step green modification process. The resulting membranes exhibit high stability in harsh organic solvents, such as dimethylsulfoxide (DMSO) and N-methyl-2-pyrrolidone (NMP), with a weight loss of less than 5 % after 30 days of immersion. These membranes also demonstrate rapid solvent transport for both polar solvents, such as methanol (86.56 L m−2 h−1 bar−1), and nonpolar solvents, such as n-hexane (48.97 L m−2 h−1 bar−1), along with high dye rejections. Additionally, the membranes possess rigid nanopores structures and consistent rejections across different pressures and solute concentrations. Most importantly, the newly synthesized amino-cyclodextrin OSN membranes are capable of separating molecules based on their 3D structures, particularly those with relatively similar molecular weights. Comparing to those reported cyclodextrin-based membranes, the newly developed amino-cyclodextrin OSN membranes show significant improvements in permeance for both polar and nonpolar organic solvents, while maintaining comparable dye rejection capabilities. The combination of fast solvent transport, excellent chemical stability, and shape selectivity makes these membranes highly promising for high-performance molecular separation in various industrial applications.

Synthesis and Additive Manufacturing of Hydrazone-Linked Covalent Organic Framework Aerogels.

Covalent Organic Frameworks (COFs) are crystalline, porous organic materials. Recent studies have demonstrated novel processing strategies for COFs to form adaptable architectures, but these have focused primarily on imine-linked COFs. This work presents a new synthesis and processing route to produce crystalline hydrazone-linked COF gels and aerogels with hierarchical porosity. The method was implemented to produce a series of hydrazone-linked COFs with different alkyl side-chain substituents, achieving control of the hydrophilicity of the final aerogel. Variation in the length of the alkyl substituents yielded materials with controllable form factors that can preferentially adsorb water or nonpolar organic solvents. Additionally, a method for additive manufacturing of hydrazone-linked COFs using hydroxymethylcellulose as a sacrificial additive is presented. This work demonstrates an effective and simple approach to the fabrication of hydrazone COF aerogels and additive manufacturing to produce hydrazone COFs of desired shape.

A thermostable organic solvent-tolerant lipase from Brevibacillus sp.: production and integrated downstream processing using an alcohol-salt-based aqueous two-phase system.

Lipases are used for the synthesis of different compounds in the chemical, pharmaceutical, and food industries. Most of the reactions are carried out in non-aqueous media and often at elevated temperature, requiring the use of organic solvent-tolerant thermostable lipases. However, most known lipases are not stable in the presence of organic solvents and at elevated temperature. In this study, an organic solvent-tolerant thermostable lipase was obtained from Brevibacillus sp. SHI-160, a moderate thermophile isolated from a hot spring in the East African Rift Valley. The enzyme was optimally active at 65°C and retained over 90% of its activity after 1 h of incubation at 70°C. High lipase activity was measured in the pH range of 6.5 to 9.0 with an optimum pH of 8.5. The enzyme was stable in the presence of both polar and non-polar organic solvents. The stability of the enzyme in the presence of polar organic solvents allowed the development of an efficient downstream processing using an alcohol-salt-based aqueous two-phase system (ATPS). Thus, in the presence of 2% salt, over 98% of the enzyme partitioned to the alcohol phase. The ATPS-recovered enzyme was directly immobilized on a solid support through adsorption and successfully used to catalyze a transesterification reaction between paranitrophenyl palmitate and short-chain alcohols in non-aqueous media. This shows the potential of lipase SHI-160 to catalyze reactions in non-aqueous media for the synthesis of valuable compounds. The integrated approach developed for enzyme production and cheap and efficient downstream processing using ATPS could allow a significant reduction in enzyme production costs. The results also show the potential of extreme environments in the East African Rift Valley as sources of valuable microbial genetic resources for the isolation of novel lipases and other industrially important enzymes.

Synthesis and spectroscopic characterization of multifunctional D-π-A benzimidazole derivatives as potential pH sensors

We report multifunctional D-π-A molecular systems having the N,N-diethylamino group as a pH sensitive donor unit connected to the electron accepting substituents such as the cyano moiety and the pH responsive benzimidazole fragment. For that purpose we have synthesized three types of derivatives, namely acrylonitrile, Schiff base and iminocoumarin derived benzimidazoles, whose photophysical characterization has been carried out in several polar and non-polar organic solvents as well as aqueous solution buffers with different pH. Computationally supported determination of species involved in prototrophic equilibria, including their respective pKa values, has been performed to aid in understanding structural and substituent effects on their UV–Vis and fluorescence spectral properties and pH sensing potentials. Both sets of results jointly indicate that all molecules are predominantly unionized under neutral conditions, while their transition towards monocationic forms, responsible for spectroscopic response changes, occurs at pH ≈ 1–4 for acrylonitriles 4–5, pH ≈ 4–5 for Schiff bases 11–12, and pH ≈ 4.5–6.5 for iminocoumarins 7–8, thus increasing their practical attractiveness for a broad range of applications in the same order.

Dispersive Liquid–Liquid Microextraction of Preservatives for Their Chromatographic Determination in Beverages

A method of dispersive liquid–liquid microextraction, based on the dispersion of an extractant by the gas phase formed as a result of a phase transition, i.e., the evaporation of a highly volatile nonpolar organic solvent (dispersant) upon heating the extraction,—is developed. The analytical capabilities of the method are shown in the determination of preservatives (sorbic and benzoic acids) in soft drinks for baby food by high-performance liquid chromatography with photometric detection. The extractant and the dispersant for the microextraction of preservatives are chosen a terpenoid and a highly volatile organochlorine solvent, respectively, which excluded the use of polar organic solvents for dispersing phases, with which the distribution coefficients are reduced. The limits of detection (3σ) for sorbic and benzoic acids are 0.3 mg/L. The developed method does not require centrifugation for phase separation

AF2400/polyketone composite OSRO membrane for organic solvent mixture separation

An organic solvent reverse osmosis (OSRO) membrane was fabricated by spin-coating a copolymer of perfluoro-2,2-dimethyl-1,3-dioxole and tetrafluoroethylene (Teflon® AF2400) onto a polyketone support membrane. The purpose of this research was to develop an OSRO membrane with different separation properties from a polyamide membrane already published in the literature. The prepared membranes had a dense and smooth active layer on the support membrane. In the pure organic solvent permeation tests, aliphatic hydrocarbons (nonpolar solvents) and aromatic hydrocarbons (nonpolar solvents) permeated through the membrane, whereas almost no alcohol permeation (polar solvents) was observed under our evaluation conditions. The separation performances of the nonpolar/polar solvent mixture systems and nonpolar/nonpolar solvent mixture systems were investigated. In the separation of 1,3,5-triisopropylbenzene from toluene, a separation factor of 31.3 with a toluene permeance of 0.07 LMH/bar was obtained, suggesting the successful separation of nonpolar organic solvents from a mixture of nonpolar solvents.

Biochemical characterization of an alkaline and detergent-stable Lipase from Fusarium annulatum Bugnicourt strain CBS associated with olive tree dieback.

This work describes a novel extracellular lipolytic carboxylester hydrolase named FAL, with lipase and phospholipase A1 (PLA1) activity, from a newly isolated filamentous fungus Ascomycota CBS strain, identified as Fusarium annulatum Bunigcourt. FAL was purified to about 62-fold using ammonium sulphate precipitation, Superdex® 200 Increase gel filtration and Q-Sepharose Fast Flow columns, with a total yield of 21%. The specific activity of FAL was found to be 3500 U/mg at pH 9 and 40°C and 5000 U/mg at pH 11 and 45°C, on emulsions of triocanoin and egg yolk phosphatidylcholine, respectively. SDS-PAGE and zymography analysis estimated the molecular weight of FAL to be 33 kDa. FAL was shown to be a PLA1 with a regioselectivity to the sn-1 position of surface-coated phospholipids esterified with α-eleostearic acid. FAL is a serine enzyme since its activity on triglycerides and phospholipids was completely inhibited by the lipase inhibitor Orlistat (40 μM). Interestingly, compared to Fusarium graminearum lipase (GZEL) and the Thermomyces lanuginosus lipase (Lipolase®), this novel fungal (phospho)lipase showed extreme tolerance to the presence of non-polar organic solvents, non-ionic and anionic surfactants, and oxidants, in addition to significant compatibility and stability with some available laundry detergents. The analysis of washing performance showed that it has the capability to efficiently eliminate oil-stains. Overall, FAL could be an ideal choice for application in detergents.

"First Come, First Served" and Threshold Effects in a Central-to-Planar-to-Helical Hierarchical Chiral Induction.

Perylene diimide tethered pillar[5]arene derivatives form aggregates in non-polar organic solvents, and the complexation of cationic amino acid ethyl ester (cAA-OEt) with the aggregates induce a central-to-planar-to-helical chirality transfer, leading to intensive circular dichroism (CD) signals having dissymmetric factors (gabs ) of up to 3.67×10-2 . The hierarchical chiral induction exhibited an intriguing threshold dose effect, namely, the chiral induction does not occur in the low concentration range of cAA-OEt but is triggered when cAA-OEt exceeds a threshold concentration. The inhibited interconversion between the Rp and Sp conformers of pillar[5]arene, which is further restricted in the aggregation, plays a crucial role in the threshold effect. When adding enantiopure cAA-OEt first to the threshold concentration and then adding an equal amount of the antipodal cAA-OEt to give cAA-OEt in racemic form, CD spectra having the same sign as the CD induced by first adding pure cAA-OEt were induced, thus showing an unprecedented "first come, first served" effect.

Full-color micro-LED display with photo-patternable and highly ambient-stable perovskite quantum dot/siloxane composite as color conversion layers

In this paper, we successfully fabricated color conversion layers (CCLs) for full-color-mico-LED display using a perovskite quantum dot (PQD)/siloxane composite by ligand exchanged PQD with silane composite followed by surface activation by an addition of halide-anion containing salt. Due to this surface activation, it was possible to construct the PQD surface with a silane ligand using a non-polar organic solvent that does not damage the PQD. As a result, the ligand-exchanged PQD with a silane compound exhibited high dispersibility in the siloxane matrix and excellent atmospheric stability due to sol–gel condensation. Based on highly ambient stable PQD/siloxane composite based CCLs, full-color micro-LED display has a 1 mm pixel pitch, about 25.4 pixels per inch (PPI) resolution was achieved. In addition, due to the thin thickness of the black matrix to prevent blue light interference, the possibility of a flexible display that can be operated without damage even with a bending radius of 5 mm was demonstrated.