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Covalent organic frameworks (COFs) are a family of engaging membrane materials for molecular separation, which remain challenging to fabricate in the form of thin-film composite membranes due to slow crystal growth and insoluble powder. Here, an additive approach is presented to construct COF-based thin-film composite membranes in 10 min via COF oligomer coating onto poly(ether ether ketone) (PEEK）ultrafiltration membranes. By the virtue of ultra-thin liquid phase and liquid-solid interface-confined assembly, the COF oligomers are fast stacked up and grow along the interface with the solvent evaporation. Benefiting from the low out-plane resistance of COFs, COF@PEEK composite membranes exhibit high solvent permeances in a negative correlation with solvent viscosity. The well-defined pore structures enable high molecular sieving ability (Mw = 300 g mol-1 ). Besides, the COF@PEEK composite membranes possess excellent mechanical integrities and steadily operate for over 150 h in the condition of high-pressure cross flow. This work not only exemplifies the high-efficiency and scale-up preparation of COF-based thin-film composite membranes but also provides a new strategy for COF membrane processing.

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Objective: The research was conducted to determine ß-carotene and antioxidant activities and screening of phytochemical substances of Moringa oleifera extraction using organic solution. Materials and Methods: 550 gm of M. oliefera leaf flour was macerated. This research was conducted by laboratory experiments using the maceration method. The extraction was performed using three kinds of solvents, which are n-hexane, ethyl acetate, and methanol; for 3 x 24 h, they were concentrated with a rotary evaporator. Then, the flavonoid, phenolic, ß-carotene isolation, and antioxidant tests were conducted using the 2,2-diphenyl-1-picrylhydrazyl on each fraction (n-hexane, ethyl acetate, and methanol). Results: The results of weighing each concentrated extract from the maceration process of each fraction (n-hexane, ethyl acetate, and methanol) were 12.67, 35.67, and 49.29 gm, with the total phenolic content (1.4595 ± 0.361, 46.5489 ± 1.832, and 39.74574 ± 0.786) and total flavonoid content of each fraction (3.3056 ± 0.039, 58.6389 ± 2.051, and 48.9056 ± 0.0809), respectively. The antioxidant activity test on the crude extract from the ethyl acetate fractionation showed that the IC50 value was 30.309 mg/ml. The ethyl acetate fraction has a high total phenolic and flavonoid content. The results of the isolation of ß-carotene from M. oleifera leaf flour were 0.4798 gm, or equivalent to 0.956% carotenoids. Conclusions: Based on the results of the research, M. oleifera leaves are identified to have a fairly high antioxidant activity, which is 30.309 mg/ml, resulting from the potential compounds in M. oleifera leaves that function as inhibitors of antioxidant activity, which are the groups of phenolic and flavonoid compounds.

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Organic fluorides can arise due to the usage of HF in technologies of gasoline production, therefore, it is necessary to identify contamination of gasoline or its components with organic fluorine. For this aim, simple and fast method is proposed. The method relies on sample dilution in xylene, followed by the solution aspiration to a high-resolution continuous source spectrometer for measurement of absorption of radiation by GaF molecule, arisen in air-acetylene flame. Gallium(III) acetylacetonate is carefully dissolved and introduced to all measured solutions at Ga concentration 5000 mg L-1. For standard addition calibration three types of samples solutions are prepared to contain: none, 50 mg L-1 and 100 mg L-1 of added fluorine. As fluorine standard 2, 2, 3, 3, 4, 4, 4-heptafluoro-1-pentanol is applied. The lowest possible flow rate of acetylene is recommended. The solution flow rate and the additional air flow rate should be adjusted to obtain not-disturbed baseline. The overlap of the GaF signal with residual signal of the OH molecule can be overcome using least square background correction. Five pixels are recommended for signal evaluation at the most sensitive 211.248 nm rotational "line". Using such conditions characteristic concentration was 3.2 mg L-1. Detection limit recalculated for initial sample was 4-10 mg L-1.•High-resolution continuum source flame molecular absorption spectrometry turned out to be an excellent tool for determination of pollution of gasoline with organic fluorine.•Due to application of GaF as a target molecule, it is possible to use a low-temperature and easy for operation air-acetylene flame.•The proposed method can be applied for analysis of alkylate, reformate, isomerizate, ethanol as well as commercial automotive and aviation gasoline.

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Fabry disease is a lysosomal storage disease arising from a deficiency of the enzyme α-galactosidase A (GLA). The enzyme deficiency results in an accumulation of glycolipids, which over time, leads to cardiovascular, cerebrovascular, and renal disease, ultimately leading to death in the fourth or fifth decade of life. Currently, lysosomal storage disorders are treated by enzyme replacement therapy (ERT) through the direct administration of the missing enzyme to the patients. In view of their advantages as drug delivery systems, liposomes are increasingly being researched and utilized in the pharmaceutical, food and cosmetic industries, but one of the main barriers to market is their scalability. Depressurization of an Expanded Liquid Organic Solution into aqueous solution (DELOS-susp) is a compressed fluid-based method that allows the reproducible and scalable production of nanovesicular systems with remarkable physicochemical characteristics, in terms of homogeneity, morphology, and particle size. The objective of this work was to optimize and reach a suitable formulation for in vivo preclinical studies by implementing a Quality by Design (QbD) approach, a methodology recommended by the FDA and the EMA to develop robust drug manufacturing and control methods, to the preparation of α-galactosidase-loaded nanoliposomes (nanoGLA) for the treatment of Fabry disease. Through a risk analysis and a Design of Experiments (DoE), we obtained the Design Space in which GLA concentration and lipid concentration were found as critical parameters for achieving a stable nanoformulation. This Design Space allowed the optimization of the process to produce a nanoformulation suitable for in vivo preclinical testing.

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Based on the nanofiltration mass transfer model, the enhanced separation behavior of ephedrine in organic solution was studied. In the experiment, the sensitive region of ethanol concentration and pH on the rejection of ephedrine was screened out by Box-Behnken central composite experiment design. Furthermore, to analyze the separation regularity of ephedrine and organic solution, the correlation between mass transfer coefficient and concentration of organic solvent was fitted with the changed organic solution by nanofiltration mass transfer mathematical model. Experiments showed the enhanced separation behavior, the decrease in the mass transfer coefficient while the increase in ethanol concentration from 20% to 40%, MWCO at 450 and pH 6.0. Under the same conditions, the enhanced separation behavior was appeared as the solvent changed into methanol and acetonitrile, the enhanced effect was positively correlated with the concentration of the three common organic solvents, and the effect order was acetonitrile>ethanol>methanol. This study took ephedrine as an example, and explored the mechanism of nanofiltration separation in the environment of organic solution, so as to provide references for nanofiltration separation for heat-sensitive traditional Chinese medicine of alkaloid.

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Based on the nanofiltration mass transfer model, the enhanced separation behavior of ephedrine in organic solution was studied. In the experiment, the sensitive region of ethanol concentration and pH on the rejection of ephedrine was screened out by Box-Behnken central composite experiment design. Furthermore, to analyze the separation regularity of ephedrine and organic solution, the correlation between mass transfer coefficient and concentration of organic solvent was fitted with the changed organic solution by nanofiltration mass transfer mathematical model. Experiments showed the enhanced separation behavior, the decrease in the mass transfer coefficient while the increase in ethanol concentration from 20% to 40%, MWCO at 450 and pH 6.0. Under the same conditions, the enhanced separation behavior was appeared as the solvent changed into methanol and acetonitrile, the enhanced effect was positively correlated with the concentration of the three common organic solvents, and the effect order was acetonitrile>ethanol>methanol. This study took ephedrine as an example, and explored the mechanism of nanofiltration separation in the environment of organic solution, so as to provide references for nanofiltration separation for heat-sensitive traditional Chinese medicine of alkaloid.

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Objective To explore the enhanced separation behavior of ferulic acid in organic solution by nanofiltration. Methods In the experiment, molecular weight cut-off (MWCO) of nanofiltration membrane, ethanol concentration, and solution pH were selected as influencing factors to find the sensitive region of ethanol concentration and pH on the retention rate of ferulic acid with Box-Behnken central composite experiment design. And then, the separation rule of ferulic acid with organic solution was analyzed, the correlation between mass transfer coefficient and concentration of organic solvent was fitted with the changed organic solution by nanofiltration mass transfer mathematical model. Results Experiments indicated that the enhanced separation behavior appeared and the mass transfer coefficient decreased as the ethanol concentration increased from 20% to 40% with MWCO 450 and pH 8.0. Under the same condition, the enhanced separation behavior happened as the solvent was changed into methanol and acetonitrile, and the enhanced effect was positively correlated with the concentration of the three common organic solvents, the effect rule was ethanol ≈ methanol > acetonitrile material. Conclusion The enhanced separation effect of nanofiltration was related to the type and concentration of organic solvent. And taking ferulic acid as an example, the mechanism of nanofiltration separation in the environment of organic solution was studied, and the results provided references for nanofiltration concentrate for heat-sensitive traditional Chinese medicine of phenolic acid in organic solution.

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Conducting polymers have promising thermoelectric application because they have many advantages including abundant elements, mechanical flexibility, and nontoxicity. The thermoelectric properties of conducting polymers strongly depend on their chemical structure and microstructure. Here, we report a novel and facile method to significantly enhance the thermoelectric properties of poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) ( PEDOT: PSS) films through a treatment with organic solutions of inorganic salts. N,N-Dimethylformamide (DMF) and a common inorganic salt like zinc chloride (ZnCl2) are used as the solvent and solute of the solutions, respectively. The treatments can significantly increase both the Seebeck coefficient and electrical conductivity of the PEDOT: PSS films. The thermoelectric properties of the PEDOT: PSS films are sensitive to the experimental conditions, such as the salt concentration, treatment temperature, and the cation of the salts. After treatment at the optimal experimental conditions, the PEDOT: PSS films can exhibit a Seebeck coefficient of 26.1 µV/K and an electrical conductivity of over 1400 S/cm at room temperature. The corresponding power factor is 98.2 µW/(m·K(2)). The mechanism for the enhancement in the thermoelectric properties is attributed to the segregation of some PSSH chains from PEDOT: PSS and the conformation change of PEDOT chains as a result of the synergetic effects of inorganic salts and DMF.

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UNLABELLED: A transparent electrode is an indispensable component of optoelectronic devices, and there as been a search for substitutes of indium tin oxide (ITO) as the transparent electrode. Poly(3,4-ethylene dioxythiophene):poly(styrenesulfonate) ( PEDOT: PSS) is a conducting polymer that is very promising as the next generation of materials for the transparent electrode if it can obtain conductivity as high as that of ITO. Here, we report the treatment of PEDOT: PSS with organic solutions to significantly enhance its conductivity. Common organic solvents like dimethylformamide and γ-butyrolactone and common organic salts like methylammonium iodide and methylammonium bromide are used for the organic solutions. The conductivity of pristine PEDOT: PSS films is only ∼0.2 S/cm, and it can be increased to higher than 2100 S/cm. The conductivity enhancement is much more significant than control treatments of PEDOT: PSS films with neat organic solvents or aqueous solutions of the organic salts. The mechanism for the conductivity enhancement is the synergetic effects of both the organic salts and organic solvents on the microstructure and composition of PEDOT: PSS. They induce the segregation of some PSSH chains from PEDOT: PSS. Highly conductive PEDOT: PSS films were studied as the transparent electrode of polymer solar cells. The photovoltaic efficiency is comparable to that with an ITO transparent electrode.

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Poly(aspartic acid) (PASP) hydrogel is a type of biodegradable and biocompatible polymer with high water absorbing ability. Traditionally, the production of PASP hydrogel is expensive, complex, environmentally unfriendly, and consumes a large amount of organic solvents, e.g. dimethylformamide or dimethylsulfoxide. This study introduces a one-step synthesis of PASP resin, in which the organic phase was replaced by distilled water and γ-aminopropyltriethoxysilane was used as the cross-linker. Absorbent ability and characteristics were determined by swelling ratio, FTIR, (13)C SSNMR, and SEM. In vitro cytotoxicity evaluation and animal skin irritation tests showed the hydrogel has body-friendly properties. Preparing PASP hydrogel in aqueous solution is promising and finds its use in many applications.

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Spray drying is a technique used to produce solid particles from liquid solutions, emulsions or suspensions. Buchi Labortechnik developed the latest generation of spray dryers, Nano Spray Dryer B-90. This study aims to obtain, directly, submicron drug particles from an organic solution, employing this equipment and using dexamethasone as a model drug. In addition, we evaluated the influence of both the type of solvent and surfactant on the properties of the powders using a 3(2) full factorial analysis. The particles were obtained with high yields (above 60%), low water content (below 2%) and high drug content (above 80%). The surface tension and the viscosity were strongly influenced by the type of solvent. The highest powder yields were obtained for the highest surface tension and the lowest viscosity of the drug solutions. The use of ionic surfactants led to higher process yields. The laser diffraction technique revealed that the particles deagglomerate into small ones with submicrometric size, (around 1 µm) that was also observed by scanning electron microscopy. Interaction between the raw materials in the spray-dried powders was verified by calorimetric analysis. Thus, it was possible to obtain dexamethasone submicrometric particles by vibrational atomization from organic solution.

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The aim of this study was to design, develop, and optimize respirable tacrolimus microparticles and nanoparticles and multifunctional tacrolimus lung surfactant mimic particles for targeted dry powder inhalation delivery as a pulmonary nanomedicine. Particles were rationally designed and produced at different pump rates by advanced spray-drying particle engineering design from organic solution in closed mode. In addition, multifunctional tacrolimus lung surfactant mimic dry powder particles were prepared by co-dissolving tacrolimus and lung surfactant mimic phospholipids in methanol, followed by advanced co-spray-drying particle engineering design technology in closed mode. The lung surfactant mimic phospholipids were 1,2-dipalmitoyl-sn-glycero-3-phosphocholine and 1,2-dipalmitoyl-sn-glycero-3-[phosphor-rac-1-glycerol]. Laser diffraction particle sizing indicated that the particle size distributions were suitable for pulmonary delivery, whereas scanning electron microscopy imaging indicated that these particles had both optimal particle morphology and surface morphology. Increasing the pump rate percent of tacrolimus solution resulted in a larger particle size. X-ray powder diffraction patterns and differential scanning calorimetry thermograms indicated that spray drying produced particles with higher amounts of amorphous phase. X-ray powder diffraction and differential scanning calorimetry also confirmed the preservation of the phospholipid bilayer structure in the solid state for all engineered respirable particles. Furthermore, it was observed in hot-stage micrographs that raw tacrolimus displayed a liquid crystal transition following the main phase transition, which is consistent with its interfacial properties. Water vapor uptake and lyotropic phase transitions in the solid state at varying levels of relative humidity were determined by gravimetric vapor sorption technique. Water content in the various powders was very low and well within the levels necessary for dry powder inhalation, as quantified by Karl Fisher coulometric titration. Conclusively, advanced spray-drying particle engineering design from organic solution in closed mode was successfully used to design and optimize solid-state particles in the respirable size range necessary for targeted pulmonary delivery, particularly for the deep lung. These particles were dry, stable, and had optimal properties for dry powder inhalation as a novel pulmonary nanomedicine.

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