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This study investigates the interface between ice and organic solvents using atomic force microscopy (AFM). Atomically flat ice surfaces were prepared and observed by AFM in 1-octanol, 1-hexanol, and 1-butanol. The results show differences in surface roughness influenced by the interaction of ice and alcohols. Young's modulus of ice was analyzed by force curve measurements, providing valuable insights into the properties of ice in liquid environments. The results showed the characteristics of the ice surface in different solvents, suggesting potential applications in understanding surface and interface phenomena associated with ice under realistic conditions. [ABSTRACT FROM AUTHOR]

We demonstrate liquid-jet photoelectron spectroscopy from a flatjet formed by the impingement of two micron-sized cylindrical jets of different aqueous solutions. Flatjets provide flexible experimental templates enabling unique liquid-phase experiments that would not be possible using single cylindrical liquid jets. One such possibility is to generate two co-flowing liquid-jet sheets with a common interface in vacuum, with each surface facing the vacuum being representative of one of the solutions, allowing face-sensitive detection by photoelectron spectroscopy. The impingement of two cylindrical jets also enables the application of different bias potentials to each jet with the principal possibility to generate a potential gradient between the two solution phases. This is shown for the case of a flatjet composed of a sodium iodide aqueous solution and neat liquid water. The implications of asymmetric biasing for flatjet photoelectron spectroscopy are discussed. The first photoemission spectra for a sandwich-type flatjet comprised of a water layer encapsulated by two outer layers of an organic solvent (toluene) are also shown. [ABSTRACT FROM AUTHOR]

[Display omitted] The formation of soft colloidal crystals, which are nonclose-packed ordered arrays of colloidal particles suspended in a solvent, is dictated by a single physical factor that yields a fixed threshold at order–disorder boundaries for different experimental conditions such as ion concentration, solvent type, and particle size. Identifying the determinant factor and its threshold value should enable the prediction of the critical concentrations of colloidal particles to form soft colloidal crystals. Soft colloidal crystals were fabricated using a series of monohydric alcohols as dispersion media and reflectance spectra were measured to locate order–disorder boundaries. The interaction forces acting between particles were also measured by employing atomic force microscopy. The interparticle forces at the order–disorder boundaries exhibited a universal threshold that was independent of the solvent types including alcohols and water. Therefore, the determinant factor for the formation of soft colloidal crystals was determined to be the force acting between the particles. Furthermore, a priori calculation of this critical force and consequently the critical particle concentration in colloidal systems was demonstrated by referring to the pressure at the liquid-to-solid transition in a hard sphere system (Alder transition). [ABSTRACT FROM AUTHOR]

The industrial separation of hydrocarbons relies on distillation. Organic solvent nanofiltration can provide an energy-efficient alternative. We prepared high performance organosiloxane membranes for fractionation of heavy aromatics. They achieved a high permeance up to 0.13 L m−2 h−1 bar−1, with a rejection rate of 88.7% for hydrocarbons with five aromatic rings. [ABSTRACT FROM AUTHOR]

A facile strategy to construct superhydrophobic coatings was carried out by one‐pot process using novel nano zero‐valent iron and hydrogen peroxide as trigger in ethanol and Tris buffer mixed system containing dopamine and 1H,1H,2H,2H‐perfluorodecanethiol (PFDT) for the first time. The polydopamine (PDA) modified by PFDT composite coating can be deposited onto various substrates including glass slides, polyurethane sheets, polytetrafluoroethylene wafers, 304 stainless steel sheets, and polyurethane sponges, revealing excellent hydrophobicity with the water contact angles from 157.1° to 162.2° and the sliding angle lower than 1°. The flourier transformed infrared spectroscopy and x‐ray photoelectron spectroscopy information of the composite coating demonstrated the successful covalent interaction between catechol group in PDA and thiol group of PFDT via Michael addition reaction. As‐prepared PFDT/PDA composite coatings exhibited enhanced chemical stability in highly acidic solutions for 6 days, alkaline aqueous solutions for 5 days, salty solutions (3.5 wt%) for 28 days, and polar organic solvents for 24 h, respectively, as well as resistance to algae adhesion. The excellent corrosion resistance and chemical stability of the composite coating and their simple, time saving and inexpensive construction process are expected to be widely applied in various areas, including marine anti‐corrosion, anti‐fouling, and oil–water separation. [ABSTRACT FROM AUTHOR]

The influence of organic solvents such as methanol and acetonitrile on the results of butachlor immunoassay in samples of rice and rice products was studied. The schemes of enzyme immunoassay using: (a) native antiserum containing specific antibodies to butachlor and antispecies antibodies labeled with horseradish peroxidase, and (b) biotinylated specific antibodies and streptavidin labeled with peroxidase are considered. The close values of IC10 (0.77 and 0.68 ng/mL, respectively) and working range (2.6–165 and 2.4–192 ng/mL, respectively) were established for the two schemes, when analyzing in a mixture of phosphate buffer and methanol in a percentage ratio of 85 : 15, respectively. For the second scheme, the detection of butachlor in butachlor in rice-containing products is shown at 80-132% of the added analyte. A comparison of sample preparation methods allows us to recommend: (a) extraction of butachlor with hexane and re-dissolution of the dry residue in a buffer with 15% methanol or (b) preparation of a methanol extract followed by 6-fold dilution with a buffer solution. [ABSTRACT FROM AUTHOR]

Tyrosol is a principle phenolic compound present in olive oil and wine with great pharmacological potentials due to its strong antioxidant property. Its application can be highly extended by increasing its lipophilicity through esterification. In this study, tyrosol esters were synthesized by enzymatic transesterification of tyrosol with vinyl esters, with a commercial lipase from Novozymes (Novozym 435, Candida antarctica lipase B (CALB) immobilized on macroporous acrylic resin beads) as the catalyst, both in organic solvents and in ionic liquids. Methyl tert-butyl ether (MTBE) was the best solvent, offering complete conversions towards the synthesis of tyrosol esters with varying chain lengths (C2-C18) within 1 h. Taking the enzymatic transesterification between tyrosol and vinyl acetate as the model reaction, 18 organic solvents and 24 ionic liquids were screened, and their solvent properties (i.e. hydrophobicity, polarity, viscosity, water activity, and partition coefficients of substrate and product) were correlated to the enzyme activity. Upon enzyme screening, four new lipases were found to be highly efficient, relative to the best-performed Novozym 435 and Lipozyme TLIM (Thermomyces lanuginosus lipase (TLL) immobilized on silica gel), in tyrosol ester synthesis. This work provides enzymatic methods of esterifying tyrosol that are much more efficient than those reported in literature, and will shed light on re-consideration of the roles of solvents in nonaqueous enzymology. [ABSTRACT FROM AUTHOR]

Thrombosis is a dangerous condition that can result in major damage. Fibrinolytic enzymes are significant therapeutic agents for thrombosis. This study focused on MsFE, a fibrinolytic protease from M. subtilissimus UCP1262, exploring its physicochemical traits and the impact of gamma radiation on its activity. Investigations included: fibrinogenolytic activity, effects of solvents and ions, gamma rays, enzyme shelf life, FTIR, CD, clotted times determination, and enzymatic kinetics. Notably, the major results obtained show the protease retained 90 % activity in organic solvents, FTIR indicated carbonyl functional groups and Circular dichroism spectroscopic studies indicated that the secondary structure (β-sheet) of enzyme remains mostly unaffected over pH 2.0–9.0, whereas considerable changes were observed in the tertiary structure. Kinetic analysis revealed altered parameters post-irradiation. Gamma radiation initially enhanced enzyme activity (10 kGy) but progressively decreased beyond 20 kGy. Metallic ions, especially magnesium, augmented irradiated enzyme activity. This study highlights gamma radiation's potential as a modulator for enhanced fibrinolytic activity, suggesting future biomedical applications. [Display omitted] • Mucor subtilissimus proves its significance as a producer of fibrinolytic proteases. • The protease degrades the α, β and γ chains of fibrinogen. • The 10 kGy radiation increased the activity of the enzyme by approximately 10 %. • Fe2+, Cu2+ and Mg2+ were able to increase the activity of the irradiated enzyme. • Produced enzymes can be a highly productive fibrinolytic for medical applications. [ABSTRACT FROM AUTHOR]

Horseradish peroxidase (HRP) was immobilized in hybrid calcium alginate-gelatin hydrogel beads by entrapment. Then, organic solubility, metal ion compatibility, pH/temperature studies of the synthesized materials have been carried out. Hybrid beads (Ca-Alg@gel-HRP) were synthesized under optimum synthesis conditions with high yield and specific activity. The synthesized bead size was determined to be approximately 0.29 mm in diameter, hydrogel structure and transparent appearance. Accordingly, the optimum pH of free HRP and Ca-Alg@gel HRP was found to be pH 6 and 5 and the optimum temperature was found to be 40 °C and 60 °C respectively. For all identified metal ions except Fe2+, the Ca-Alg@gel HRP had a higher activity than the free HRP. In the presence of 1 mM Na+, Ca2+, Mg2+, Ba2+, Cu2+, Ni2+, Mn2+, Hg2+ ions, the activity increased by more than 20%. The relative activity was also approximately 153%, 150% and 145% in 2.5 mM chloroform, glycerol and DMF. Free enzyme activity was reduced by more than 30%. The Ca-Alg@gel HRP at room temperature and 4 °C retained most of its activity after 14 days. In cycle 5, it had half the activity. As a conclusion, it may have significant potential in a number of industrial processes, particularly in organic synthesis, because it is tolerant to metal ions and organic solvents and is a cheap, practical and simple immobilization method. [ABSTRACT FROM AUTHOR]

BACKGROUND: Environmental and ecological hazards caused by the accumulation of polyethylene terephthalate (PET) are becoming a global concern. The use of enzymes to address the plastic crisis has achieved many successes, but the difficulty in degrading high‐crystallinity PET has limited its application. Numerous studies have investigated the degradation of PET with arbitrary crystallinity to bis‐2‐(2‐hydroxyethyl) terephthalate (BHET) using chemical pre‐treatment methods such as glycolysis, but few have tested its biocompatibility with enzymatic alliances. RESULTS: Herein, we report the enzymatic characterization and subsequent engineering of the state‐of‐the‐art IsPETasePA and MHETase (where MHET is mono(2‐hydroxyethyl) terephthalate), a dual‐enzyme system which can be used for the degradation from BHET to a single‐product terephthalate (TPA). Modulators, including surfactants, organic solvents and metal ions, enhanced the enzyme activity of IsPETasePA and MHETase by up to 1.1‐fold and 2.3‐fold, respectively. 100% TPA yield (BHET of 25 g L−1) was achieved within 5 h. We also analyzed the mechanism of optimal ion modulator modification by dynamics simulation, and it synergistically achieved enhancement of MHET degradation ability by improving stability and binding energy. CONCLUSION: The introduction of modulators improves the efficiency of the dual‐enzyme system in degrading BHET. This work provides a valuable strategy for the complete degradation of BHET to TPA, laying the groundwork for the realization of PET recycling. © 2024 Society of Chemical Industry (SCI). [ABSTRACT FROM AUTHOR]

Organic solvent nanofiltration (OSN) plays important roles in pharmaceutical ingredients purification and solvent recovery. However, the low organic solvent permeance under cross‐flow operation of OSN membrane hampers their industrial applications. Herein, we report the construction of coffee‐ring structured membrane featuring high OSN permeance. A water‐insoluble crystal monomer that dissolved in EtOH/H2O mixed solvent was designed to react with trimesoyl chloride via interfacial polymerization. Owing to the diffusion of EtOH to n‐hexane, coffee‐ring nanostructure on the support membrane appeared, which served as the template for construction of coffee‐ring structured membrane. The optimal nanostructured membrane demonstrated 2.6‐fold enhancement in the effective surface area with reduced membrane thickness. Resultantly, the membrane afforded a 2.7‐fold enhancement in organic solvent permeance, e.g. ~13 LMH/bar for MeOH, without sacrificing the rejection ability. Moreover, due to the rigid monomer structure, the fabricated membrane shows distinctive running stability in active pharmaceutical ingredients purification and the ability for concentration of medicines. [ABSTRACT FROM AUTHOR]

An assembly between 1,4-dicarboxylbenzene-2,3-dithiol (H2dcbdt) and different transition metal ions successfully produced 2D metal–organic frameworks (M-dcbdt, M = Ni, Co or Fe) composed of unprecedented butterfly-shaped metal-bis(dithiolene) (MS4) linkers in one-pot fashion. Such strategy provides easier access to the [MS4]-rich network and lowers the prerequisite to explore their applications. [ABSTRACT FROM AUTHOR]

We report the synthesis of a heterogenous silver catalyst stabilized by bidentate N-heterocyclic carbene ligands. The heterogeneous nature of the catalyst is inherently derived from the unprecedented internal structural features observed for the catalyst. X-ray studies show that the silver complex forms a two-dimensional cross-linked system, where one dimension of the network is formed by inorganic polymer strings and the second direction is formed by the interconnection of these inorganic strings with NHC bidentate ligands. This organized internal arrangement renders the complex insoluble in many common organic solvents and enables its utilization as a reusable heterogeneous catalyst in multicomponent A3 coupling reactions. Notably, propargylic amines were obtained with yields of up to 97%, and the catalyst demonstrated reusability for six cycles. These results can facilitate the further development of heterogeneous NHC catalysts. [ABSTRACT FROM AUTHOR]

Natural membrane receptors are proteins that can report on changes in the concentration of external chemical messengers. Messenger binding to a receptor produces conformational changes that are relayed through the membrane into the cell; this information allows cells to adapt to changes in their environment. Artificial membrane receptors (R)‐1 and (S)‐1 are helical α‐aminoisobutyric acid (Aib) foldamers that replicate key parts of this information relay. Solution‐phase 19F NMR spectroscopy of zinc(II)‐capped receptor 1, either in organic solvent or in membrane‐mimetic micelles, showed messenger binding produced an enrichment of either left‐ or right‐handed screw‐sense; the chirality of the bound messenger was relayed to the other receptor terminus. Furthermore, in situ production of a chemical messenger in the external aqueous environment could be detected in real‐time by a racemic mixture of receptor 1 in micelles. The hydrolysis of insoluble anhydrides produced carboxylate in the aqueous phase, which bound to the receptors and gave a distinct 19F NMR output from inside the hydrophobic region of the micelles. [ABSTRACT FROM AUTHOR]

Polymer materials suffer mechano-oxidative deterioration or degradation in the presence of molecular oxygen and mechanical forces. In contrast, aerobic biological activities combined with mechanical stimulus promote tissue regeneration and repair in various organs. A synthetic approach in which molecular oxygen and mechanical energy synergistically initiate polymerization will afford similar robustness in polymeric materials. Herein, aerobic mechanochemical reversible-deactivation radical polymerization was developed by the design of an organic mechano-labile initiator which converts oxygen into activators in response to ball milling, enabling the reaction to proceed in the air with low-energy input, operative simplicity, and the avoidance of potentially harmful organic solvents. In addition, this approach not only complements the existing methods to access well-defined polymers but also has been successfully employed for the controlled polymerization of (meth)acrylates, styrenic monomers and solid acrylamides as well as the synthesis of polymer/perovskite hybrids without solvent at room temperature which are inaccessible by other means. Polymer materials suffer mechano-oxidative deterioration or degradation in the presence of molecular oxygen and mechanical forces. Here the authors demonstrate a synthetic approach in which molecular oxygen and mechanical energy synergistically initiate polymerization and affords robustness in polymeric materials. [ABSTRACT FROM AUTHOR]

Dimethylallyl tryptophan synthases (DMATSs) are aromatic prenyltransferases that catalyze the transfer of a prenyl moiety from a donor to an aromatic acceptor during the biosynthesis of microbial secondary metabolites. Due to their broad substrate scope, DMATSs are anticipated as biotechnological tools for producing bioactive prenylated aromatic compounds. Our study explored the substrate scope and product profile of a recombinant RePT, a novel DMATS from the thermophilic fungus Rasamsonia emersonii. Among a variety of aromatic substrates, RePT showed the highest substrate conversion for l-tryptophan and l-tyrosine (> 90%), yielding two mono-prenylated products in both cases. Nine phenolics from diverse phenolic subclasses were notably converted (> 10%), of which the stilbenes oxyresveratrol, piceatannol, pinostilbene, and resveratrol were the best acceptors (37–55% conversion). The position of prenylation was determined using NMR spectroscopy or annotated using MS2 fragmentation patterns, demonstrating that RePT mainly catalyzed mono-O-prenylation on the hydroxylated aromatic substrates. On l-tryptophan, a non-hydroxylated substrate, it preferentially catalyzed C7 prenylation with reverse N1 prenylation as a secondary reaction. Moreover, RePT also possessed substrate-dependent organic solvent tolerance in the presence of 20% (v/v) methanol or DMSO, where a significant conversion (> 90%) was maintained. Our study demonstrates the potential of RePT as a biocatalyst for the production of bioactive prenylated aromatic amino acids, stilbenes, and various phenolic compounds. Key points: • RePT catalyzes prenylation of diverse aromatic substrates. • RePT enables O-prenylation of phenolics, especially stilbenes. • The novel RePT remains active in 20% methanol or DMSO. [ABSTRACT FROM AUTHOR]

Lipases are enzymes that hydrolyze long-chain carboxylic esters, and in the presence of organic solvents, they catalyze organic synthesis reactions. However, the use of solvents in these processes often results in enzyme denaturation, leading to a reduction in enzymatic activity. Consequently, there is significant interest in identifying new lipases that are resistant to denaturing conditions, with extremozymes emerging as promising candidates for this purpose. Lip7, a lipase from Geobacillus sp. ID17, a thermophilic microorganism isolated from Deception Island, Antarctica, was recombinantly expressed in E. coli C41 (DE3) in functional soluble form. Its purification was achieved with 96% purity and 23% yield. Enzymatic characterization revealed Lip7 to be a thermo-alkaline enzyme, reaching a maximum rate of 3350 U mg−1 at 50 °C and pH 11.0, using p-nitrophenyl laurate substrate. Notably, its kinetics displayed a sigmoidal behavior, with a higher kinetic efficiency (kcat/Km) for substrates of 12-carbon atom chain. In terms of thermal stability, Lip7 demonstrates stability up to 60 °C at pH 8.0 and up to 50 °C at pH 11.0. Remarkably, it showed high stability in the presence of organic solvents, and under certain conditions even exhibited enzymatic activation, reaching up to 2.5-fold and 1.35-fold after incubation in 50% v/v ethanol and 70% v/v isopropanol, respectively. Lip7 represents one of the first lipases from the bacterial subfamily I.5 and genus Geobacillus with activity and stability at pH 11.0. Its compatibility with organic solvents makes it a compelling candidate for future research in biocatalysis and various biotechnological applications. [ABSTRACT FROM AUTHOR]

Membrane-based pervaporation (PV) for organic solvent dehydration is of great significance in the chemical and petrochemical industries. In this work, high-aluminum ZSM-5 zeolite membranes were synthesized by a fluoride-assisted secondary growth on α-alumina tubular supports using mordenite framework inverted (MFI) nanoseeds (~110 nm) and a template-free synthesis solution with a low Si/Al ratio of 10. Characterization by XRD, EDX, and SEM revealed that the prepared membrane was a pure-phase ZSM-5 zeolite membrane with a Si/Al ratio of 3.8 and a thickness of 2.8 µm. Subsequently, two categories of PV performance parameters (i.e., flux versus separation factor and permeance versus selectivity) were used to systematically examine the effects of operating conditions on the PV dehydration performance of different organic solvents (methanol, ethanol, n-propanol, and isopropanol), and their PV mechanisms were explored. Employing permeance and selectivity effectively disentangles the influence of operating conditions on PV performance, thereby elucidating the inherent contribution of membranes to separation performance. The results show that the mass transfer during PV dehydration of organic solvents was mainly dominated by the adsorption–diffusion mechanism. Furthermore, the diffusion of highly polar water and methanol molecules within membrane pores had a strong mutual slowing-down effect, resulting in significantly lower permeance than other binary systems. However, the mass transfer process for water/low-polar organic solvent (ethanol, n-propanol, and isopropanol) mixtures was mainly controlled by competitive adsorption caused by affinity differences. In addition, the high-aluminum ZSM-5 zeolite membrane exhibited superior PV dehydration performance for water/isopropanol mixtures. [ABSTRACT FROM AUTHOR]

The ninhydrin reaction is commonly used for the detection of amino acids. However, in the literature, different conditions with respect to the buffer system, its pH and concentration, type of organic solvent, incubation time, and temperature, as well as the concentrations of the reagents, are described. To identify the most suitable conditions, colour development with reagents of varying compositions and different reaction temperatures and times were investigated using asparagine as a model amino acid. Asparagine was selected since it is one of the most abundant free amino acids in many types of samples. The optimal reaction mixture consisted of 0.8 mol L−1 potassium acetate, 1.6 mol L−1 acetic acid, 20 mg mL−1 ninhydrin and 0.8 mg mL−1 hydrindantin in DMSO/acetate buffer 40/60 (v/v) (final concentrations). The best reaction condition was heating the samples in 1.5 mL reaction tubes to 90 °C for 45 min. Afterwards, the samples were diluted with 2-propanol/water 50/50 (v/v) and the absorbance was measured at 570 nm. The proteinogenic amino acids showed a similar response except for cysteine and proline. The method was highly sensitive and showed excellent linearity as well as intra-day and inter-day reproducibility. [ABSTRACT FROM AUTHOR]

This study used conservative one variable-at-a-time study and statistical surface response methods to increase the yields of an extracellular thermostable protease secreted by a newly identified thermophilic Bacillus subtilis BSP strain. Using conventional optimization techniques, physical parameters in submerged fermentation were adjusted at the shake flask level to reach 184 U/mL. These physicochemical parameters were further optimized by statistical surface response methodology using Box Behnken design, and the protease yield increased to 295 U/mL. The protease was purified and characterized biochemically. Both Ca2+ and Fe2+ increased the activity of the 36 kDa protease enzyme. Based on its strong inhibition by ethylenediaminetetracetate (EDTA), the enzyme was confirmed to be a metalloprotease. The protease was also resistant to various organic solvents (benzene, ethanol, methanol), surfactants (Triton X-100), sodium dodecyl sulfate (SDS), Tween 20, Tween-80 and oxidants hydrogen per oxide (H2O2). Characteristics, such as tolerance to high SDS and H2O2 concentrations, indicate that this protease has potential applications in the pharmaceutical and detergent industries. [ABSTRACT FROM AUTHOR]

Sodium (Na) metal batteries (SMBs) have attracted many attentions because of high specific capacity and low redox potential. However, SMBs encounter several crucial challenges including Na dendrites growth, severe interfacial side reactions and safe issues from liquid organic electrolyte. In this study, a non‐flammable 1,2‐bis (1,1,2,2‐tetrafluoroethoxy) ethane (TFEE) aided ionic liquid (IL) electrolyte (TILE) is reported with sodium bis(trifluoromethylsulfonyl)imide (NaTFSI) salt and N‐methyl‐N‐propylpyrrolidinium bis(fluorosulfonyl)imide ([Py13][FSI]) IL solvent. The IL solvent contains plentiful organic cations and anions, which helps to provide a cationic shielding effect by [Py13]+ cations and regulate the Na+ solvation structure with more FSI− and TFSI− anions. The unique solvation structure of Na+ facilitates a stable inorganic‐rich solid electrolyte interphase (SEI), effectively inhibiting unstable Na deposition and suppressing side reactions between the electrolyte and Na‐metal in SMBs. Therefore, the Na3V2(PO4)3 (NVP)||Na cells with TILE can deliver good rate capability and superior cycling performance with capacity retention of 95.5% and Coulombic efficiency of ≈99.9% after 2000 cycles at 5C rate and 25 °C. The high‐voltage NaNi0.33Fe0.33Mn0.33O2(NFM)||Na cells with TILE can also deliver good cycling performance with capacity retention of 92% after 150 cycles in the voltage range of 2.0–4.1 V at 0.5C rate and 25 °C. [ABSTRACT FROM AUTHOR]

Metabolite extraction is the critical first-step in metabolomics experiments, where it is generally regarded to inactivate and remove proteins. Here, arising from efforts to improve extraction conditions for polar metabolomics, we discover a proteomic landscape of over 1000 proteins within metabolite extracts. This is a ubiquitous feature across several common extraction and sample types. By combining post-resuspension stable isotope addition and enzyme inhibitors, we demonstrate in-extract metabolite interconversions due to residual transaminase activity. We extend these findings with untargeted metabolomics where we observe extensive protein-mediated metabolite changes, including in-extract formation of glutamate dipeptide and depletion of total glutathione. Finally, we present a simple extraction workflow that integrates 3 kDa filtration for protein removal as a superior method for polar metabolomics. In this work, we uncover a previously unrecognized, protein-mediated source of observer effects in metabolomics experiments with broad-reaching implications across all research fields using metabolomics and molecular metabolism. Metabolite extraction with organic solvents is assumed to remove/denature proteins. Here, the authors uncover a vast landscape of >1,000 proteins in metabolite extracts. These proteins can retain catalytic activity and drive post-extraction metabolite changes, obscuring biological interpretation. [ABSTRACT FROM AUTHOR]

Implantable drug delivery systems formed upon injection offer a host of advantages, including localized drug administration, sustained release, minimized side effects, and enhanced patient compliance. Among the various techniques utilized for the development of in situ forming drug implants, solvent-induced phase inversion emerges as a particularly promising approach. However, synthetic polymer-based implants have been associated with undesirable effects arising from polymer degradation. In response to this challenge, a novel category of drug delivery systems, known as phospholipids-based phase separation gels (PPSGs), has emerged. These gels, characterized by their low initial viscosity, exhibit injectability and undergo rapid transformation into in situ implants when exposed to an aqueous environment. A typical PPSG formulation comprises biodegradable components, such as phospholipids, pharmaceutical oil, and a minimal amount of ethanol. The minimized organic solvents in the composition show good biocompatibility. And the relatively simple composition holds promise for industrial-scale manufacturing. This comprehensive review provides an overview of the principles and advancements in PPSG systems, with specific emphasis on their suitability as drug delivery systems for a wide range of active pharmaceutical ingredients (APIs), spanning from small molecules to peptides and proteins. Additionally, we explore the critical parameters and underlying principles governing the formulation of PPSG-based drug delivery strategies, offering valuable insights on optimization strategies. [ABSTRACT FROM AUTHOR]

This work highlighted the proficient and naturally safe methodology for the phenol synthesis using biocatalyst lipase. The development of sustainable synthetic protocol for various organic transformations is an important area of research attracts researchers to avoid use of volatile and hazardous organic solvents in reaction for greener and eco-friendly protocols. Lipase is subclass of esterase enzymes and acts as biocatalyst with industrial significance. They carry out biochemical transformation in non-aqueous and aqueous phases quickly. To further make the process more specific Design Expert software was used for the optimization of synthesize phenol for maximum % Yield and % Purity. Effect of temperature, Concentration of Catalyst, and Volume of Water was selected as an independent factor to get the maximum % Yield and % Purity of the phenol. The results confirmed the mathematical model robustness and justify experimental design. Therefore, the current protocol for synthesis of phenols from phenylboronic acid is greenest and environmentally benign alternative. The current convention has many benefits, like phenomenal product yields, reduced time of reaction, simple procedure to work up, and extensive substrate scope, cost-effective and also lipase was recuperated and reused multiple times without significant loss of its catalytic activity. [ABSTRACT FROM AUTHOR]

Photoactive supramolecular porphyrin assemblies are attractive molecules for light‐harvesting applications. This is due to their relatively non‐toxicity, biological activities and charge and energy exchange characteristics. However, the extreme cost associated with their synthesis and requirements for toxic organic solvents during purification pose a challenge to the sustainability characteristics of their applications. This work presents the first report on the sustainable synthesis, spectroscopic and photophysical characterizations of a near‐infrared (NIR) absorbing Ca(II)‐meso‐tetrakis (4‐hydroxyphenyl)porphyrin using an electrolyzed pyrrole solution. The latter was obtained by cycling the pyrrole solution across the silver nanodumbbell particle surface at room temperature. The electrolyzed solution condensed readily with acidified p‐hydroxybenzaldehyde, producing the targeted purple porphyrin. The non‐electrolyzed pyrrole solution formed a green substance with significantly different optical properties. Remarkable differences were observed in the voltammograms of the silver nanodumbbell particles and those of the conventional gold electrode during the pyrrole cycling, suggesting different routes of porphyrin formation. The rationale behind these formations and the associated mechanisms were extensively discussed. Metalation with aqueous Ca2+ ion caused a Stokes shift of 38.75 eV. The current study shows the advantage of the electrochemical method towards obtaining sustainable light‐harvesting porphyrin at room temperature without the need for high‐energy‐dependent conventional processes. [ABSTRACT FROM AUTHOR]

As a biodegradable and biocompatible polymer material, polyglycolic acid is attracting more and more attention in the field of polymeric and biomedical materials. Consequently, the study of the transformation between different crystal forms of glycolide, the monomer of polyglycolic acid, is of great importance, because crystal forms of glycolide determine the stabilities and properties of polyglycolic acid products polymerized under different conditions in industry. Herein, this article reports the synthesis and crystallization of α‐ and β‐glycolide controlled by the type of organic solvents and/or temperatures, during which an intermediate crystal form of β′‐glycolide is newly observed. The transformation between α‐, β‐, and β′‐glycolide is investigated in detail, and the stabilities of different crystal forms are illustrated via the controlled experiments under different relative humidity (RH) as well as the theoretical calculations, which should provide fundamental concepts and guidance for the industrial production of glycolide and optimization of polyglycolic acid products. [ABSTRACT FROM AUTHOR]

The solubility problem of conjugated polymers in nonhalogenated solvents limits the application of nonhalogenated solvents in Organic solar cells (OSCs). By combining with a hot spin‐coating process, efficient PM6:BTP‐BO‐4F:GS‐ISO ternary OSCs are prepared by employing o‐xylene as a solvent. After adding 10 wt% content of GS‐ISO to PM6:BTP‐BO‐4F, the surface morphology in the active layers is improved and the charge extraction, transport, and collection in OSCs are enhanced. Compared with the efficiency of PM6:BTP‐BO‐4F OSCs (16.25%), an efficiency of 18.63% is achieved for PM6:BTP‐BO‐4F:GS‐ISO ternary OSCs. Moreover, PM6:BTP‐BO‐4F:GS‐ISO ternary OSCs with an efficiency of 14.13% are prepared in air. The work provides a new strategy for preparing efficient and environmentally friendly OSCs using green solvents. [ABSTRACT FROM AUTHOR]

Stable nickel (Ni) isotopes have shown great potential for investigating planetary accretion processes, mantle–crust magmatism, and paleo-marine evolution. The development of an economical and time-efficient separation method for Ni isotope analysis holds significant value within the realm of Ni isotope research. Previous purification methods for Ni isotope analysis have typically relied on either multi-column procedures or the utilization of significant quantities of organic reagents, such as acetic acid, acetone, and dimethylglyoxime. In this study, a novel two-column chromatographic separation procedure was presented for the determination of Ni isotope compositions in geological materials. A cation resin (AG50W-X8) was utilized in conjunction with diluted HCl and HF to effectively remove a substantial portion of matrix elements. Subsequently, trace amounts (100–200 μL) of Ni-spec resin were used for further purification of Ni. This relatively simple purification scheme for Ni isotope analysis effectively reduces the use of organic reagents and the amount of Ni-spec resin compared to previous methods that relied on multi-column separation and organic reagent extraction. Ni isotopic compositions were analyzed using multi-collector inductively coupled plasma mass spectrometry (MC-ICP-MS). The instrumental mass discrimination of Ni isotopic ratios was corrected for using the double spike (DS) combined with the sample–standard bracketing (SSB) method. The Ni isotope compositions (δ60Ni) of in-house standards (SCP and CUG) were −0.06 ± 0.05‰ (2 SD, n = 104) and 0.36 ± 0.06‰ (2 SD, n = 97), respectively. Furthermore, the measured δ60Ni values of various geological reference materials (BCR-2, BHVO-2, BIR-1, DTS-1, DTS-2b, SDO-1, GSP-2, and W-2a from the USGS; JB-1b from the GSJ; GSR-2, GSR-3, GSR-4, GSR-5, and GSR-10 from the NRCGA) were consistent with previous studies within measurement error. Additionally, the δ60Ni values of AGV-1 from the USGS, as well as those of GSR-10, GSR-12, GSR-15, GSR-17, GSR-18, and GSR-19 from the NRCGA are reported here for the first time. Based on repeated measurements of pure solutions and reference materials, the long-term reproducibility of δ60Ni values was better than ± 0.06‰ (2 SD). Consequently, our study presents a relatively straightforward purification method for Ni for its isotopic analysis using only trace amounts of organic reagents and Ni-spec resin. [ABSTRACT FROM AUTHOR]

The study illustrated here aims on an organic solvent tolerant lipase from Staphylococcus capitis (SCL). The gene part, encoding the mature lipase, was cloned and sequenced. The concluded polypeptide sequence, equivalent to the protein, consist of 388 amino acid residues with a molecular mass of about 45 kDa. A structure-based alignment of the SCL amino acid sequence shows high identities with those many staphylococcal lipases. From this alignment of sequences, the catalytic triad (Ser 117, Asp 308 and His 347) of SCL could be identified. The mature part of the SCL was expressed in Escherichia coli and the recombinant lipase (r-SCL) was purified to homogeneity. The purified r-SCL presented a quite interesting stability at low temperatures (< 30 °C) and the enzyme was found to be highly stable in polar organic solvent and at a pH ranging from 3 to 12. After that, we have demonstrated that the recombinant enzyme may be implicated in the biodegradability of oily wastewater from effluents of fast-food restaurants; the maximum conversion yield into fatty acids obtained at 30 °C, was 65%. [ABSTRACT FROM AUTHOR]

A new extracellular protease from Bacillus subtilis strain MPK with collagenolytic activity was isolated and purified. Fish skin which otherwise would be treated as waste is used as substrate for the production of protease. Using various techniques such as ammonium sulphate precipitation and ion exchange chromatography, protease was purified and characterized subsequently. Protease of approximately 61 kDa molecular weight was purified by 135.7-fold with 18.42% enzyme recovery. The protease showed effective properties like pH and temperature stability over a broad range with optimum pH 7.5 and temperature 60 °C. K m and V max were found to be 1.92 mg ml−1 and 1.02 × 10−4 mol L−1 min−1, respectively. The protease exhibited stability in various ions, surfactants, inhibitors and organic solvents. Subsequently, the protease was successfully utilized for collagen hydrolysis to generate collagen peptides; thus, the produced protease would be a potential candidate for multifaceted applications in food and pharmaceutical industries due to its significant characteristics and collagenolytic properties. • Bacillial collagenases have a remarkably high collagenolytic activity. • Using fish waste, a new extracellular protease from Bacillus subtilis strain MPK was isolated, purified and characterized. • The protease exhibited stability in various ions, surfactants, inhibitors and organic solvents. • The purified protease demonstrated the ability to produce collagen peptides. [ABSTRACT FROM AUTHOR]

Summary: This study investigates the benefits of green‐lipped mussels containing bioavailable PUFAs and inflammation‐modulating oil extracts. The goal is to find the best method for extracting lipids from two types of raw materials with strong immunomodulatory, anti‐inflammatory and antioxidant properties using organic solvents and supercritical carbon dioxide (CO2) techniques. The lipid classes are analysed using TLC‐FID and GC–MS to detect FFAs, while DPPH determines antioxidant levels. The cytokine production of IL‐6 and TNF‐α in LPS‐stimulated mouse macrophages is measured using ELISA. The results show that while supercritical CO2 is the most effective method for extracting lipids, the content can vary depending on the source and technique. The major FFAs found include EPA, Palmitic acid, DHA, and Palmitoleic acid, with PUFAs, particularly omega 3, being the most dominant. Samples exhibit potent radical scavenging in 2000 μg mL−1, similar to ascorbic acid at 62.5 μg mL−1 (62.2 ± 15.36%). The cells release more TNF‐α than IL‐6, and solvent extraction was found to regulate the immune response more effectively. In conclusion, the extracts contain significant amounts of EPA/DHA and variable FFAs, suggesting potential anti‐inflammatory effects. However, further validation in alternative in vitro models is necessary. [ABSTRACT FROM AUTHOR]

Mole fraction solubilities have been experimentally determined for 2,3-dimethoxybenzoic acid dissolved in propanenitrile and diisopropyl ether, in two more alkyl alkanoates (tert-butyl acetate, methyl butanoate), and in ten more alcohols (1-pentanol, 1-hexanol, 1-heptanol, 1-octanol, 2-methyl-1-propanol, 2-butanol, 2-pentanol, 3-methyl-1-butanol, 4-methyl-2-pentanol, cyclopentanol) at 298.15 K using a spectrophotometric method of chemical analysis based on the Beer-Lambert law. Experiment-based solute descriptors for the monomeric form of the dissolved carboxylic acid solute have been calculated using the results from our solubility measurements, combined with published solubility data taken from the chemical literature. The calculated solute descriptors provide a reasonably accurate mathematical description of the observed solubility data, with the overall standard deviation between the observed and back-calculated values being 0.074 log units. The solute descriptors further suggest that the carboxylic acid solute does not undergo intramolecular hydrogen bonding in the 28 organic solvents considered in the current study. [ABSTRACT FROM AUTHOR]

In situ electrochemical potential-induced fast synthesis the ultrathin MAF-4 membrane on polymer support with a satisfactory H 2 /CO 2 separation performance and excellent stability. [Display omitted] Metal-Organic Framework (MOF) membranes act as selective layers have offered unprecedented opportunities for energy-efficient and cost-effective gas separation. Searching for the green and sustainable synthesis method of dense MOF membrane has received huge attention in both academia and industry. In this work, we demonstrate an in situ electrochemical potential-induced synthesis strategy to aqueously fabricate Metal Azolate Framework-4 (MAF-4) membranes on polypropylene (PP) support. The constant potential can induce the heterogeneous nucleation and growth of MAF-4, resulting an ultrathin membrane with the thickness of only 390 nm. This high-quality membrane exhibits a high H 2 /CO 2 separation performance with the H 2 permeance as high as 1565.75 GPU and selectivity of 11.6. The deployment of this environment friendly one-step fabrication method under mild reaction conditions, such as low-cost polymer substrate, water instead of organic solvent, room temperature and ambient pressure shows great promise for the scale-up of MOF membranes. [ABSTRACT FROM AUTHOR]

• PDA-HKUST-1 interlayer enhances the stability of OSN membrane structure. • PA layer thickness of PA/ PDA -HKUST-1 0.6 /PEI membrane is about 14 nm. • PA/CaAlg-HKUST-1 6 /PEI membrane has good solvent resistance. Polydopamine (PDA) and metal-organic skeleton HKUST-1 were co-deposited on the base membrane of hexamethylenediamine (HDA)-crosslinked polyetherimide (PEI) ultrafiltration membrane as the interlayer, and high-throughput organic solvent nanofiltration membrane (OSN) was prepared by interfacial polymerization and solvent activation reaction. The polyamide (PA) layer surface roughness from 28.4 nm in PA/PEI to 78.3 nm in PA/PDA-HKUST-1 0.6 /PEI membrane, reduced the thickness of the separation layer from 79 to 14 nm, and significantly improved the hydrophilic, thermal and mechanical properties. The flux of the PA/PDA-HKUST-1 0.6 /PEI membrane in a 0.1 g/L Congo Red (CR) ethanol solution at 0.6 MPa test pressure reached 21.8 L/(m2·hr) and the rejection of CR was 92.8%. Solvent adsorption test, N, N-dimethylformamide (DMF) immersion experiment, and long-term operation test in ethanol showed that the membranes had high solvent tolerance. The solvent flux test demonstrated that, under the test pressure of 0.6 MPa, the flux of different solvents ranked as follows: methanol (56.9 L/(m2·hr)) > DMF (39.6 L/(m2·hr)) > ethanol (31.2 L/(m2·hr)) > IPA (4.5 L/(m2·hr)) > N - hexane (1.9 L/(m2·hr)). The ability of the membranes to retain dyes in IPA/water dyes solution was also evaluated. The flux of the membrane was 30.4 L/(m2·hr) and the rejection of CR was 91.6% when the IPA concentration reached 50%. This OSN membrane-making strategy is economical, environment-friendly and efficient, and has a great application prospect in organic solvent separation systems. [Display omitted] [ABSTRACT FROM AUTHOR]

Essential oils are emerging as alternatives to conventional pest control chemicals. Lippia graveolens Kunth (Mexican oregano) is a source of essential oils and during conventional extraction, the biomass generated is discarded as waste; however, reports show that this biomass is still a rich source of essential oils. Conventional essential oil extraction causes contamination and utilizes toxic solvents. Deep eutectic solvents (DESs) offer low toxicity, biodegradability, high selectivity, and yields comparable to organic solvents. This study obtained essential oil from Lippia graveolens biomass via hydrodistillation with ultrasound-assisted DES pretreatment. This research aimed to optimize the extraction of essential oil from Lippia graveolens biomass using ultrasound-assisted DESs and assess its in vitro and in vivo inhibitory effect on C. asianum. The response variables were extraction yield and total reducing capacity. Optimal conditions were determined using a central composite rotatable design, considering solid-to-liquid ratio (0.38 g/mL), ultrasonic amplitude (45.05%), and time (7.47 min). The optimized oil, with thymol (48%) as the predominant component, exhibited more volatile compounds than conventional hydrodistillation. Fungicidal assays highlighted its potential in controlling anthracnose in papaya fruits caused by C. asianum, making ultrasound-assisted DES pretreatment a promising alternative for obtaining essential oil from botanical byproducts. [ABSTRACT FROM AUTHOR]

Vegetable oils are rich in health-beneficial compounds, including fatty acids, phenolic compounds, natural antioxidants, and fat-soluble vitamins. However, oil extraction methods can influence their composition. This study aims to understand the chemical basis for developing a green process to extract oils from two Andean seeds, cañihua (Chenopodium pallidicaule) and tarwi (Lupinus mutabilis). Ethanol, considered a green solvent, is compared to petroleum ether used at the laboratory level and hexane used at the industrial scale for extracting oils. The extraction efficiency is assessed in terms of yield, fatty acids profile, polar and neutral lipids, tocopherols, phenolic compounds, and antioxidant capacity. The chemical composition of edible commercial oils, such as sunflower, rapeseed, and olive oils, was used as a reference. Hexane had the highest extraction yield, followed by petroleum ether and ethanol. However, the oils extracted with ethanol having yields of tarwi 15.5% and cañihua 5.8%, w/w showed the significatively superior content of tocopherols (α, γ, and δ); phenolic compounds; and antioxidant capacity. In addition, ethanol-extracted (EE) oils have higher levels of polar lipids, such as phosphatidylcholine and phosphatidylinositol, than those extracted with the other solvents. Remarkably, EE oils presented comparable or slightly higher levels of monounsaturated fatty acids than those extracted with hexane. Finally, compared to the commercial oils, tarwi and cañihua EE oils showed lower but acceptable levels of oleic, linoleic and palmitic acids and a wider variety of fatty acids (10 and 13, respectively). The composition of tarwi and cañahua oils extracted with ethanol includes compounds associated with nutritional and health benefits, providing a sustainable alternative for oil production. [ABSTRACT FROM AUTHOR]

The mutual separation of Am and Cm is conducted using an alkyl-diamide amine (ADAAM(EH)) extractant. ADAAM(EH) exhibits an extremely high separation factor (SF) with respect to Am and Cm separation (SF = 5.9) in an HNO3-n-dodecane system. The batch-wise multistage extractions are performed using a system containing 0.2 M ADAAM(EH) and 1.5 M HNO3, with their distribution ratios (D) of the system for Am and Cm equal to 2.55 and 0.434, respectively. In this multistage extraction, 3 stages of feed, 9 stages involving scrubbing, and 11 stages involving the use of an organic solvent give 96.5% and 1.06% yields of Am and Cm, respectively. After the mutual separation, the aqueous and the organic phases including actinides increase four times in volume compared to the feed solution. Additional extraction steps are to reduce the volume of the solutions including actinides. We use tetraethyl diglycolamide (TEDGA)/water for Am concentration, tetraoctyl diglycolamide/n-dodecane for the intermediate extraction, and TEDGA/water for stripping in the Cm concentration step. Taking the additional steps, Am and Cm can be recovered in just two or three stages in the aqueous phases. [ABSTRACT FROM AUTHOR]

In this work, we presented the results of density functional theory calculations for the static first hyperpolarizability for one representative push–pull π‐conjugated molecule, 2‐dimethylamino‐7‐nitrofluorene, in six organic solvents (p‐dioxane, chloroform, tetrahydrofuran, acetone, acetonitrile, and dimethylsulfoxide) spanning a large range of dielectric constant. The finite‐field formalism was used to calculate the longitudinal component of the static first hyperpolarizability. The solvent effect was calculated using two distinct polarizable continuum solvation models: the linear response and the state‐specific polarizable continuum models. The calculations demonstrated the existence of solvation model effects on the property of interest, which warranted further analysis. The two‐level model was then employed to illustrate the impact of solvation model. Our findings suggested that the state‐specific polarizable continuum model gave a decrease of the dipole moment of the excited state in high polarity solvent for a bathochromic molecule whose excited state should have a larger polarization than its ground state. [ABSTRACT FROM AUTHOR]

Levulinic acid (LA) is one of the top bio‐based platform molecules that can be converted into many valuable chemicals. Herein, we report the sustainable synthesis of LA acid from various sugars using heteropolyacid catalysts. By using a Box–Behnken design of experiment, both LA yield (up to 69 mol%) and complete suppression of parasitic humin formation could be achieved within a 5 h reaction time at 140°C using fructose as a substrate. The effects of various reaction parameters like temperature, sugar concentration, addition of organic co‐solvent and reaction time on LA yield and humin formation were examined in a three‐dimensional space. Moreover, the results could be successfully transferred to other sugars like glucose or cellobiose, paving the way for an atom‐efficient and sustainable LA synthesis process. [ABSTRACT FROM AUTHOR]

Understanding solvent‐solute interactions is essential to designing and synthesising soft materials with tailor‐made functions. Although the interaction of the solute with the solvent mixture is more complex than the single solvent medium, solvent mixtures are exciting to unfold several unforeseen phenomena in supramolecular chemistry. Here, we report two unforeseen pathways observed during the hierarchical assembly of cationic perylene diimides (cPDIs) in water and amphiphilic organic solvent (AOS) mixtures. When the aqueous supramolecular polymers (SPs) of cPDIs are injected into AOS, initially kinetically trapped short SPs are formed, which gradually transform into thermodynamically stable high aspect ratio SP networks. Using various experimental and theoretical investigations, we found that this temporal evolution follows two distinct pathways depending on the nature of the water‐AOS interactions. If the AOS is isopropanol (IPA), water is released from cPDIs into bulk IPA due to strong hydrogen bonding interactions, which further decreases the monomer concentration of cPDIs (Pathway‐1). In the case of dioxane AOS, cPDI monomer concentration further increases as water is retained among cPDIs (Pathway‐2) due to relatively weak interactions between dioxane and water. Interestingly, these two pathways are accelerated by external stimuli such as heat and mechanical agitation. [ABSTRACT FROM AUTHOR]

The preparation of highly rigid cobalt(II)- and copper(II)–organic frameworks incorporating a tetralactam [2]rotaxane as a ligand is described. The interlocked ligand is functionalized with two pairs of carboxylate groups placed at each counterpart, thus limiting its dynamics within the crystal. The solid structure of the metal–organic rotaxane frameworks showed different, unprecedented polycatenation modes of grids, depending on the employed metal, providing great rigidity to the structures. This rigidity has been evaluated by using single crystal X-ray diffraction analyses of the cobalt(II)–organic frameworks embedded in different solvents, observing that the lattices remain unchanged. Thus, this research demonstrates that rigid and robust materials with permanent porosity can be achieved using dynamic ligands. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Organic solvent nanofiltration (OSN) has enormous potential for transforming the way organic solvents are purified and recovered in the chemical industry. Apart from conventional thin film composite (TFC) nanofiltration membrane fabrication methods, a greener, simpler, and more efficient approach has been utilized to fabricate OSN membranes. Oxidative polymerization of an aqueous solution of a pyrrole monomer on a hydrolyzed/crosslinked polyacrylonitrile (H-PAN/C-PAN) support yielded a dense polypyrrole (PPy) skin layer consisting of a conjugated carbonaceous polyaryl network. The presence of multiple amino groups (>NH) in the PPy chain develops extensive hydrogen bonding with the –COOH and –NH groups present in the H-PAN/C-PAN support. The shift in the ATR-FTIR peaks of PPy upon deposition on the H-PAN/C-PAN support confirmed the interaction between PPy and the H-PAN/C-PAN support. When the OSN performance of the fabricated membranes was studied, the PPy@C-PAN/PETP membrane showed a better performance in terms of rejection of model solutes including charged and neutral molecules compared to the PPy@H-PAN/PETP membrane. Both membranes rejected >99% of Rose Bengal, Congo red, and Eriochrome black T used as model solutes in the current study. For the neutral molecules, PPy@H-PAN@PETP was able to reject 44% of triphenylbenzene (TPB) and >99% of hexaphenylbenzene (HPB), whereas PPy@C-PAN@PETP rejected 72% of TPB and >99% of HPB. In the case of methylene blue, a rejection of 48% was found for PPy@H-PAN/PETP while a rejection of 82% was recorded for PPy@C-PAN/PETP. Moreover, the permeance of n-hexane was found to be 9.3 L m−2 h−1 bar−1 for PPy@H-PAN/PETP and 3.3 L m−2 h−1 bar−1 for the PPy@C-PAN/PETP membrane. [ABSTRACT FROM AUTHOR]

Reductive amination of carbonyl compounds and nitro compounds represents a straightforward way to attain imines or secondary amines, but it is difficult to control the product selectivity. Herein, we report the selective formation of C−N or C=N bond readily manipulated through a solvent‐induced hydrogen bond bridge, facilitating the swift photocatalytic reductive coupling process. The reductive‐coupling of nitro compounds with carbonyl compounds using formic acid and sodium formate as the hydrogen donors over CdS nanosheets selectively generates imines with C=N bonds in acetonitrile solvent; while taking methanol as solvent, the C=N bonds are readily hydrogenated to the C−N bonds via hydrogen‐bonding activation. Experimental and theoretical study reveals that the building of the hydrogen‐bond bridge between the hydroxyl groups in methanol and the N atoms of the C=N motifs in imines facilitates the transfer of hydrogen atoms from CdS surface to the N atoms in imines upon illumination, resulting in the rapid hydrogenation of the C=N bonds to give rise to the secondary amines with C−N bonds. Our method provides a simple way to control product selectivity by altering the solvents in photocatalytic organic transformations. [ABSTRACT FROM AUTHOR]

The biochemical composition and bioavailability of particulate organic matter (POM) were studied in relation to abiotic (water column stratification, macronutrient concentrations) and biotic factors (phytoplankton biomass and functional groups) in the open Ross Sea and coastal area of Terra Nova Bay, Antarctica, during the austral summer 2017. The presence of different sub-systems was highlighted by spatial and temporal variations of all the considered variables, characterised by higher concentrations of particulate organic carbon and nitrogen in Terra Nova Bay, where diatoms dominated, while in the open Ross Sea was higher the contribution of haptophytes (Phaeocystis antarctica Karsten, 1905). The southernmost Ross Sea was characterised by significantly higher concentrations of carbohydrates in the entire water column. High lipid contribution and low photosynthetic activity indicated aged POM, suggesting that POM was composed mainly by the remnants of previous haptophytes production. The higher lability of the carbohydrates indicated that an increase of haptophytes in the area could alter the biogeochemical C cycle, reducing the storage of refractory carbon in the depths, and favouring the transfer and respiration of C in the trophic web, with a decrease of export rate in the Ross Sea. [ABSTRACT FROM AUTHOR]

Acetole, a polar molecule that cannot form hydrogen bonds on its own, interacts with solvent molecules mainly through the lone pair of its nitrogen atom and the π electrons of its CN triple bond. Interestingly, acetonitrile exhibits an unexpected strengthening of the triple bond's force constant in an aqueous environment, leading to an upshift (blueshift) in the corresponding stretching vibration: this effect contrasts with the usual consequence of hydrogen bonding on the vibrational frequencies of the acceptor groups, that is, frequency redshift. This investigation elucidates this phenomenon using Raman spectroscopy to examine the behavior of acetonitrile in organic solvent, water, and silver ion aqueous solutions, where an even more pronounced upshift is observed. Raman spectroscopy is particularly well suited for analyzing aqueous solutions due to the minimal scattering effect of water molecules across most of the vibrational spectrum. Computational approaches, both static and dynamical, based on Density Functional Theory and hybrid functionals, are employed here to interpret these findings, and accurately reproduce the vibrational frequencies of acetonitrile in different environments. Our calculations also allow an explanation for this unique behavior in terms of electric charge displacements. On the other hand, the study of the interaction of acetonitrile with water molecules and metal ions is relevant for the use of this molecule as a solvent in both chemical and pharmaceutical applications. [ABSTRACT FROM AUTHOR]

In the study, the synthesis process involved the reaction of dimethylolbutyric acid and polytetramethylene ether glycol 1000 (PTMG1000) with hexamethylene diisocyanate (H12MDI), taking advantage of their mutual dissolution at high temperatures. The chain‐extension reaction with 1,4‐butanediol (BDO) was successfully conducted without the use of organic solvents. The emulsification reaction was carried out using the polyurethane prepolymer at 60% solids content, along with aqueous dispersions of polyethylene glycol (PEG) with varying molecular weights and amounts as interfacially active agents. Fourier transform infrared spectroscopy analysis suggested potential hydrogen bonding interactions between the PEG molecular chain and the polyurethane chain. Rheometer analysis demonstrated a significant reduction in viscosity with the addition of 1–5 wt.% PEG, accompanied by an increase in average particle size. This phenomenon was attributed to the formation of a hydrophilic lubrication layer of PEG around the water‐based polyurethane (WPU) microcells. Among them, WPU films containing 4 wt.% PEG4000 not only exhibited soft properties with a mechanical elongation rate exceeding 2000% but also showed excellent storage stability. The addition of long‐chain PEG facilitated the formation of a lubrication layer between the microcells, contributing to spatial stabilization and reducing particle aggregation at high solids content. It is noteworthy that this solvent‐free process, without any organic solvents, together with the adjusted PEG content, successfully synthesized waterborne polyurethanes with low viscosity and high solids content. This provides a new sustainable and environmentally friendly method for the future production of waterborne polyurethanes. [ABSTRACT FROM AUTHOR]

Pterocaulon polystachyum is a species of pharmacological interest for providing volatile and non-volatile extracts with antifungal and amebicidal properties. The biological activities of non-volatile extracts may be related to the presence of coumarins, a promising group of secondary metabolites. In the present study, leaves and inflorescences previously used for the extraction of essential oils instead of being disposed of were subjected to extraction with supercritical CO2 after pretreatment with microwaves. An experimental design was followed to seek the best extraction condition with the objective function being the maximum total extract. Pressure and temperature were statistically significant factors, and the optimal extraction condition was 240 bar, 60 °C, and pretreatment at 30 °C. The applied mathematical models showed good adherence to the experimental data. The extracts obtained by supercritical CO2 were analyzed and the presence of coumarins was confirmed. The extract investigated for cytotoxicity against bladder tumor cells (T24) exhibited significant reduction in cell viability at concentrations between 6 and 12 μg/mL. The introduction of green technology, supercritical extraction, in the exploration of P. polystachyum as a source of coumarins represents a paradigm shift with regard to previous studies carried out with this species, which used organic solvents. Furthermore, the concept of circular bioeconomy was applied, i.e., the raw material used was the residue of a steam-distillation process. Therefore, the approach used here is in line with the sustainable exploitation of native plants to obtain extracts rich in coumarins with cytotoxic potential against cancer cells. [ABSTRACT FROM AUTHOR]

Conductive polymers, such as polyaniline (PANI), have interesting applications, ranging from flexible electronics, energy storage devices, sensors, antistatic or anticorrosion coatings, etc. However, the full exploitation of conductive polymers still poses a challenge due to their low processability. The use of compatible stabilizers to obtain dispersible and stable colloids is among the possible solutions to overcome such drawbacks. In this work, potato starch was used as a steric stabilizer for the preparation of colloidal polyaniline (emeraldine salt, ES)/starch composites by exploiting the oxidative polymerization of aniline in aqueous solutions with various starch-to-aniline ratios. The polyaniline/starch bio-composites were subjected to structural, spectroscopic, thermal, morphological, and electrochemical analyses. The samples were then tested for their dispersibility/solubility in a range of organic solvents. The results demonstrated the formation of PANI/starch biocomposites with a smaller average size than starch particles, showing improved aqueous dispersion and enhanced solubility in organic solvents. With respect to previously reported PANI-EB (emeraldine base)/starch composites, the novel colloids displayed a lower overall crystallinity, but the conductive nature of PANI-ES enhanced its electrochemical properties, resulting in richer redox chemistry, particularly evident in its oxidation behavior, as observed through cyclic voltammetry. Finally, as proof of the improved processability, the colloids were successfully integrated into a thin polyether sulfone (PES) membrane. [ABSTRACT FROM AUTHOR]