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1.
Nat Commun ; 15(1): 3919, 2024 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-38724503

RESUMEN

Biological macromolecules can condense into liquid domains. In cells, these condensates form membraneless organelles that can organize chemical reactions. However, little is known about the physical consequences of chemical activity in and around condensates. Working with model bovine serum albumin (BSA) condensates, we show that droplets swim along chemical gradients. Active BSA droplets loaded with urease swim toward each other. Passive BSA droplets show diverse responses to externally applied gradients of the enzyme's substrate and products. In all these cases, droplets swim toward solvent conditions that favor their dissolution. We call this behavior "dialytaxis", and expect it to be generic, as conditions which favor dissolution typically reduce interfacial tension, whose gradients are well-known to drive droplet motion through the Marangoni effect. These results could potentially suggest alternative physical mechanisms for active transport in living cells, and may enable the design of fluid micro-robots.


Asunto(s)
Albúmina Sérica Bovina , Albúmina Sérica Bovina/química , Albúmina Sérica Bovina/metabolismo , Animales , Ureasa/metabolismo , Ureasa/química , Solubilidad , Bovinos , Solventes/química , Tensión Superficial
2.
Sci Rep ; 14(1): 10679, 2024 05 09.
Artículo en Inglés | MEDLINE | ID: mdl-38724534

RESUMEN

The supercritical antisolvent (SAS) process was a green alternative to improve the low bioavailability of insoluble drugs. However, it is difficult for SAS process to industrialize with limited production capacity. A coaxial annular nozzle was used to prepare the microcapsules of aprepitant (APR) and polyvinylpyrrolidone (PVP) by SAS with N, N-Dimethylformamide (DMF) as solvent. Meanwhile, the effects of polymer/drug ratio, operating pressure, operating temperature and overall concentration on particles morphology, mean particle diameter and size distribution were analyzed. Microcapsules with mean diameters ranging from 2.04 µm and 9.84 µm were successfully produced. The morphology, particle size, thermal behavior, crystallinity, drug content, drug dissolution and residual amount of DMF of samples were analyzed. The results revealed that the APR drug dissolution of the microcapsules by SAS process was faster than the unprocessed APR. Furthermore, the drug powder collected every hour is in the kilogram level, verifying the possibility to scale up the production of pharmaceuticals employing the SAS process from an industrial point of view.


Asunto(s)
Aprepitant , Cápsulas , Tamaño de la Partícula , Povidona , Solventes , Cápsulas/química , Povidona/química , Solventes/química , Aprepitant/química , Solubilidad , Dimetilformamida/química , Liberación de Fármacos , Composición de Medicamentos/métodos , Temperatura
3.
Int J Mol Sci ; 25(9)2024 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-38731888

RESUMEN

The interaction of heparin with antithrombin (AT) involves a specific sequence corresponding to the pentasaccharide GlcNAc/NS6S-GlcA-GlcNS3S6S-IdoA2S-GlcNS6S (AGA*IA). Recent studies have revealed that two AGA*IA-containing hexasaccharides, which differ in the sulfation degree of the iduronic acid unit, exhibit similar binding to AT, albeit with different affinities. However, the lack of experimental data concerning the molecular contacts between these ligands and the amino acids within the protein-binding site prevents a detailed description of the complexes. Differential epitope mapping (DEEP)-STD NMR, in combination with MD simulations, enables the experimental observation and comparison of two heparin pentasaccharides interacting with AT, revealing slightly different bound orientations and distinct affinities of both glycans for AT. We demonstrate the effectiveness of the differential solvent DEEP-STD NMR approach in determining the presence of polar residues in the recognition sites of glycosaminoglycan-binding proteins.


Asunto(s)
Antitrombinas , Heparina , Espectroscopía de Resonancia Magnética , Simulación de Dinámica Molecular , Oligosacáridos , Unión Proteica , Heparina/química , Heparina/metabolismo , Oligosacáridos/química , Oligosacáridos/metabolismo , Antitrombinas/química , Antitrombinas/metabolismo , Espectroscopía de Resonancia Magnética/métodos , Sitios de Unión , Solventes/química , Mapeo Epitopo/métodos , Humanos
4.
Int J Mol Sci ; 25(9)2024 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-38731902

RESUMEN

Investigation of chiroptical polymers in the solution phase is paramount for designing supramolecular architectures for photonic or biomedical devices. This work is devoted to the case study of poly(propylene oxide) (PPO) optical activity in several solvents: benzonitrile, carbon disulfide, chloroform, ethyl acetate, and p-dioxane. To attain information on the interactions in these systems, rheological testing was undertaken, showing distinct variations of the rheological parameters as a function of the solvent type. These aspects are also reflected in the refractive index dispersive behavior, from which linear and non-linear optical properties are extracted. To determine the circular birefringence and specific rotation of the PPO solutions, the alternative method of the channeled spectra was employed. The spectral data were correlated with the molecular modeling of the PPO structural unit in the selected solvents. Density functional theory (DFT) computational data indicated that the torsional potential energy-related to the O1-C2-C3-O4 dihedral angle from the polymer repeating unit-was hindered in solvation environments characterized by high polarity and the ability to interact via hydrogen bonding. This was in agreement with the optical characterization of the samples, which indicated a lower circular birefringence and specific rotation for the solutions of PPO in ethyl acetate and p-dioxane. Also, the shape of optical rotatory dispersion curves was slightly modified for PPO in these solvents compared with the other ones.


Asunto(s)
Solventes , Solventes/química , Glicoles de Propileno/química , Polipropilenos/química , Polímeros/química , Modelos Moleculares , Rotación , Enlace de Hidrógeno , Reología
5.
AAPS PharmSciTech ; 25(5): 105, 2024 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-38724807

RESUMEN

The formulation of microspheres involves a complex manufacturing process with multiple steps. Identifying the appropriate process parameters to achieve the desired quality attributes poses a significant challenge. This study aims to optimize the critical process parameters (CPPs) involved in the preparation of naltrexone microspheres using a Quality by Design (QbD) methodology. Additionally, the research aims to assess the drug release profiles of these microspheres under both in vivo and in vitro conditions. Critical process parameters (CPPs) and critical quality attributes (CQAs) were identified, and a Box-Behnken design was utilized to delineate the design space, ensuring alignment with the desired Quality Target Product Profile (QTPP). The investigated CPPs comprised polymer concentration, aqueous phase ratio to organic phase ratio, and quench volume. The microspheres were fabricated using the oil-in-water emulsion solvent extraction technique. Analysis revealed that increased polymer concentration was correlated with decreased particle size, reduced quench volume resulted in decreased burst release, and a heightened aqueous phase ratio to organic phase ratio improved drug entrapment. Upon analyzing the results, an optimal formulation was determined. In conclusion, the study conducted in vivo drug release testing on both the commercially available innovator product and the optimized test product utilizing an animal model. The integration of in vitro dissolution data with in vivo assessments presents a holistic understanding of drug release dynamics. The QbD approach-based optimization of CPPs furnishes informed guidance for the development of generic pharmaceutical formulations.


Asunto(s)
Química Farmacéutica , Preparaciones de Acción Retardada , Sistemas de Liberación de Medicamentos , Liberación de Fármacos , Microesferas , Naltrexona , Tamaño de la Partícula , Naltrexona/química , Naltrexona/administración & dosificación , Naltrexona/farmacocinética , Animales , Química Farmacéutica/métodos , Preparaciones de Acción Retardada/química , Sistemas de Liberación de Medicamentos/métodos , Polímeros/química , Emulsiones/química , Composición de Medicamentos/métodos , Solubilidad , Solventes/química
6.
Se Pu ; 42(5): 481-486, 2024 Apr 08.
Artículo en Chino | MEDLINE | ID: mdl-38736392

RESUMEN

Ibandronate sodium, a third-generation diphosphate drug used worldwide to treat osteoporosis, has the advantages of convenient use, low toxicity, and significant therapeutic effects. However, the residual organic solvents in the synthesis process of sodium ibandronate not only have a negative impact on the efficacy of the drug, but also lead to a decrease in drug stability. Moreover, if the residual amounts of these solvents exceed safety standards, they may pose serious threats to human health. This study successfully established a convenient and efficient method based on headspace-gas chromatography (HS-GC) for the simultaneous determination of five residual solvents (methanol, acetone, benzene, toluene, 1-pentanol) in the raw materials of ibandronate sodium. The results indicated that satisfactory analytical performance can be achieved by using DB-624 capillary column (30 m×0.32 mm×1.8 µm) and a flame ionization detector in conjunction with headspace autosampling and a temperature program. The specific operating conditions included an initial temperature of 40 ℃, with a hold of 2 min, followed by a temperature ramp first to 200 ℃ at a rate of 5 ℃/min and then to 240 ℃ at a rate of 20 ℃/min, with a hold of 5 min. Nitrogen with a flow rate of 1 mL/min and split ratio of 14∶1 was used as the carrier gas. The headspace vial temperature was maintained at 80 ℃, and the sample equilibration time was 20 min. Under the established analytical conditions, good linear relationships were obtained between the mass concentrations of methanol (72-216 µg/mL), acetone (120-360 µg/mL), benzene (0.048-0.144 µg/mL), toluene (21.36-64.08 µg/mL), and 1-pentanol (120-360 µg/mL) and their corresponding peak areas, with correlation coefficients (r) greater than 0.990. The limits of detection for these solvents were 2.88, 0.011, 0.90, 0.24, and 0.024 ng/mL, respectively, with limits of quantification of 11.5, 0.043, 3.6, 0.96, and 0.096 ng/mL, respectively. Furthermore, the recoveries of these solvents ranged from 86.3% to 101.9%, with relative standard deviations (RSDs, n=3) of less than 2.49%. The proposed method is simple, accurate, reliable, and suitable for the rapid and simultaneous determination of five residual solvents in the raw materials of ibandronate sodium. This study has important practical significance in improving drug safety and ensuring public health.


Asunto(s)
Ácido Ibandrónico , Solventes , Cromatografía de Gases/métodos , Solventes/química , Ácido Ibandrónico/análisis , Difosfonatos/análisis , Contaminación de Medicamentos
7.
J Sep Sci ; 47(9-10): e2300925, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38726740

RESUMEN

Deep eutectic solvents (DESs), as a new type of eco-friendly solvent, have attracted increasing attention on the extraction and separation of flavonoid compounds from various samples, owing to their excellent properties such as biodegradability and ease of handling with very low toxicity. This article provides a status review of the applications of DESs in the extraction of flavonoids, including the introduction of flavonoid compounds, the properties and superiority of DESs, and extraction methods (ultrasonic-assisted extraction, heating reflux extraction, matrix solid-phase dispersion, and solid-phase extraction). Finally, prospects and challenges in the application of DESs on extraction and separation are extensively elucidated and critically reviewed.


Asunto(s)
Disolventes Eutécticos Profundos , Flavonoides , Extracción en Fase Sólida , Flavonoides/aislamiento & purificación , Flavonoides/química , Disolventes Eutécticos Profundos/química , Solventes/química
8.
Cryo Letters ; 45(3): 158-167, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38709187

RESUMEN

BACKGROUND: Aquaporins (AQPs) are essential proteins that facilitate the rapid movement of water and cryoprotective agents (CPAs) during the cryopreservation process, and ensure the cryo-tolerance of sperm cells. OBJECTIVE: This study evaluated the preservation of aquaporin levels in human sperm after undergoing freezing using natural deep eutectic solvents (NADES) as CPAs for cryoprotection. MATERIALS AND METHODS: From June 2021 to October 2022, 35 semen samples with normal sperm parameters were acquired from the Mehr Infertility Treatment Institute in Rasht, Iran. The samples were divided into several groups for analysis: control group (not frozen), group frozen with SpermFreeze Solution, and groups frozen with different NADESs, including ChS, ChX, ChU, ChG, GlyP, and EtP. After thawing, various aspects for each group were assessed, including the integrity and condensation of sperm chromatin, viability, motility, integrity of acrosome, and the expression of AQP1, AQP3, AQP7, AQP8, and AQP9 genes. RESULTS: The analysis of gene expression revealed that freezing with ChS and GlyP preserved the expression of the AQP1 and AQP3 genes compared to the control group. Regarding AQP7 and AQP8, significant differences were not observed in expression levels between certain NADES groups (e.g., ChS, ChU, and GlyP) and the control group. Additionally, samples frozen with specific NADESs, such as ChS, ChG, EtP, and GlyP, exhibited preserved levels of AQP9 expression when compared to the control group. CONCLUSION: These findings emphasize the importance of NADES in preserving the expression of aquaporins in cryopreserved human sperm and their important fertility parameters. Doi.org/10.54680/fr24310110512.


Asunto(s)
Acuaporinas , Criopreservación , Crioprotectores , Preservación de Semen , Motilidad Espermática , Espermatozoides , Humanos , Masculino , Criopreservación/métodos , Acuaporinas/genética , Acuaporinas/metabolismo , Espermatozoides/metabolismo , Espermatozoides/efectos de los fármacos , Crioprotectores/farmacología , Motilidad Espermática/efectos de los fármacos , Preservación de Semen/métodos , Solventes/química , Adulto , Supervivencia Celular/efectos de los fármacos
9.
AAPS PharmSciTech ; 25(5): 93, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38693316

RESUMEN

Tolterodine tartrate (TOTA) is associated with adverse effect, high hepatic access, varied bioavailability, slight aqueous solubility, and short half-life after oral delivery. Hansen solubility parameters (HSP, HSPiP program), experimental solubility (T = 298.2 to 318.2 K and p = 0.1 MPa), computational (van't Hoff and Apelblat models), and thermodynamic models were used to the select solvent(s). HSPiP predicted PEG400 as the most suitable co-solvent based on HSP values (δd = 17.88, δp = 4.0, and δh = 8.8 of PEG400) and comparable to the drug (δd = 17.6, δp = 2.4, and δh = 4.6 of TOTA). The experimental mole fraction solubility of TOTA was maximum (xe = 0.0852) in PEG400 confirming the best fit of the prediction. The observed highest solubility was attributed to the δp and δh interacting forces. The activity coefficient (ϒi) was found to be increased with temperature. The higher values of r2 (linear regression coefficient) and low RMSD (root mean square deviation) indicated a good correlation between the generated "xe" data for crystalline TOTA and the explored models (modified Apelblat and van't Hoff models). TOTA solubility in "PEG400 + water mixture" was endothermic and entropy-driven. IR (immediate release product) formulation can be tailored using 60% PEG400 in buffer solution for 2 mg of TOTA in 0.25 mL (dosing volume). The isotonic binary solution was associated with a pH of 7.2 suitable for sub-Q delivery. The approach would be a promising alternative with ease of delivery to children and aged patients.


Asunto(s)
Solubilidad , Solventes , Termodinámica , Tartrato de Tolterodina , Humanos , Tartrato de Tolterodina/administración & dosificación , Tartrato de Tolterodina/química , Tartrato de Tolterodina/farmacocinética , Solventes/química , Polietilenglicoles/química , Disponibilidad Biológica , Química Farmacéutica/métodos , Inyecciones Subcutáneas , Sistemas de Liberación de Medicamentos/métodos
10.
Luminescence ; 39(5): e4759, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38693721

RESUMEN

Colloidal semiconductor quantum dots have many potential optical applications, including quantum dot light-emitting diodes, single-photon sources, or biological luminescent markers. The optical properties of colloidal quantum dots can be affected by their dielectric environment. This study investigated the photoluminescence (PL) decay of thick-shell gradient-alloyed colloidal semiconductor quantum dots as a function of solvent refractive index. These measurements were conducted in a wide range of delay times to account for both the initial spontaneous decay of excitons and the delayed emission of excitons that has the form of a power law. It is shown that whereas the initial spontaneous PL decay is very sensitive to the refractive index of the solvent, the power-law delayed emission of excitons is not. Our results seem to exclude the possibility of carrier self-trapping in the considered solvents and suggest the existence of trap states inside the quantum dots. Finally, our data show that the average exciton lifetime significantly decreases as a function of the solvent refractive index. The change in exciton lifetime is qualitatively modeled and discussed.


Asunto(s)
Coloides , Luminiscencia , Puntos Cuánticos , Solventes , Puntos Cuánticos/química , Solventes/química , Coloides/química , Refractometría , Mediciones Luminiscentes , Semiconductores , Factores de Tiempo
11.
Proc Natl Acad Sci U S A ; 121(21): e2318905121, 2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38739787

RESUMEN

We propose that spontaneous folding and molecular evolution of biopolymers are two universal aspects that must concur for life to happen. These aspects are fundamentally related to the chemical composition of biopolymers and crucially depend on the solvent in which they are embedded. We show that molecular information theory and energy landscape theory allow us to explore the limits that solvents impose on biopolymer existence. We consider 54 solvents, including water, alcohols, hydrocarbons, halogenated solvents, aromatic solvents, and low molecular weight substances made up of elements abundant in the universe, which may potentially take part in alternative biochemistries. We find that along with water, there are many solvents for which the liquid regime is compatible with biopolymer folding and evolution. We present a ranking of the solvents in terms of biopolymer compatibility. Many of these solvents have been found in molecular clouds or may be expected to occur in extrasolar planets.


Asunto(s)
Solventes , Biopolímeros/química , Solventes/química , Medio Ambiente Extraterrestre/química , Evolución Molecular , Agua/química
12.
Pak J Pharm Sci ; 37(1): 147-154, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38741411

RESUMEN

Zeravschania khorasanica, a species endemic to the eastern part of Iran, possesses distinct characteristics that distinguish it from its two closely related species. This research employed five different extraction techniques to identify the active components, total phenolic content and in vitro antioxidant activity of the extract. Furthermore, hydro-distillation was utilized for GC/MS analysis to determine the composition of the essential oil. The total phenolic content was estimated using the Folin-Ciocalteu assay and the antioxidant capacity was evaluated using the DPPH radical scavenging test. The findings revealed that ethanolic Soxhlet extraction yielded the highest efficiency in extracting total phenolic content (88.19 ±1.99 gallic acid mg/100g). In contrast, water maceration extraction demonstrated the highest antioxidant activity (68.1 ±5.4%). Interestingly, the study uncovered that there is no significant positive correlation between the phenolic content and the antioxidant activity of the plant. Additionally, HPLC analysis identified three phenolic constituents in the extract. The Soxhlet extraction method yielded the highest levels of chlorogenic acid (5.8 ppm), caffeic acid (4.1 ppm) and salicylic acid (10.3 ppm). As per the GC/MS analysis, a total of eleven compounds were identified. The predominant compounds were elemicin at 58.19% and trans--bergamotene at 25.78%.


Asunto(s)
Antioxidantes , Apiaceae , Cromatografía de Gases y Espectrometría de Masas , Fenoles , Extractos Vegetales , Solventes , Antioxidantes/aislamiento & purificación , Antioxidantes/análisis , Antioxidantes/farmacología , Antioxidantes/química , Fenoles/análisis , Fenoles/aislamiento & purificación , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Extractos Vegetales/farmacología , Irán , Solventes/química , Apiaceae/química , Cromatografía Líquida de Alta Presión , Aceites Volátiles/química , Aceites Volátiles/aislamiento & purificación , Aceites Volátiles/farmacología , Compuestos de Bifenilo/química , Picratos/química , Ácidos Cafeicos/aislamiento & purificación , Ácidos Cafeicos/análisis
13.
Spectrochim Acta A Mol Biomol Spectrosc ; 316: 124346, 2024 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-38692105

RESUMEN

Considering the health relevance of Chagas' disease, recent research efforts have focused on developing more efficient drug delivery systems containing nifurtimox (NFX). This paper comprehensively investigates NFX through conformational analysis and spectroscopic characterization. Using a conformer-rotamer ensemble sampling tool (CREST-xtb), five distinct conformers of NFX were sampled within a 3.0 kcal mol-1 relative energy window. Subsequently, such structures were used as inputs for geometry optimization by density functional theory (DFT) at B3LYP-def2-TZVP level of theory. Notably, harmonic vibrational frequencies were calculated to establish an in-depth comparison with experimental results and existing literature for the NFX or similar molecules and functional groups, thereby achieving a widely reasoned assignment of the mid-infrared band absorptions for the first time. Moreover, UV-VIS spectra of NFX were obtained in several solvents, enabling the determination of the molar absorptivity coefficient for the two electronic transitions observed for NFX. Among the aprotic solvents, a bathochromic effect was observed in the function of the dielectric constants. Furthermore, a hypochromic effect was observed when the drug was dissolved in protic solvents. These findings offer crucial support for new drug delivery systems containing NFX while demonstrating the potential of spectrophotometric studies in establishing quality control assays for NFX drug products.


Asunto(s)
Enfermedad de Chagas , Conformación Molecular , Nifurtimox , Enfermedad de Chagas/tratamiento farmacológico , Nifurtimox/química , Espectrofotometría Ultravioleta , Tripanocidas/química , Modelos Moleculares , Teoría Funcional de la Densidad , Trypanosoma cruzi/efectos de los fármacos , Solventes/química
14.
J Chromatogr A ; 1725: 464930, 2024 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-38696889

RESUMEN

Unsuitable sample preparation may result in loss of important analytes and consequently affect the outcome of untargeted metabolomics. Due to species differences, different sample preparations may be required within the same biological matrix. The study aimed to compare the in-house sample preparation method for urine with methods from literature and to investigate the transferability of sample preparation from human urine to rat urine. A total of 12 different conditions for protein precipitation were tested, combining four different extraction solvents and three different reconstitution solvents using an untargeted liquid-chromatography high resolution mass spectrometry (LC-HRMS) metabolomics analysis. Evaluation was done based on the impact on feature count, their detectability, as well as the reproducibility of selected compounds. Results showed that a combination of methanol as extraction and acetonitrile/water (75/25) as reconstitution solvent provided improved results at least regarding the total feature count. Additionally, it was found that a higher amount of methanol was most suitable for extraction of rat urine among the tested conditions. In comparison, human urine requires significantly less volume of extraction solvent. Overall, it is recommended to systematically optimize both, the extraction method, and the reconstitution solvent for the used biofluid and the individual analytical settings.


Asunto(s)
Metabolómica , Metanol , Solventes , Animales , Ratas , Metabolómica/métodos , Humanos , Solventes/química , Metanol/química , Reproducibilidad de los Resultados , Cromatografía Liquida/métodos , Acetonitrilos/química , Masculino , Espectrometría de Masas/métodos , Orina/química , Agua/química , Urinálisis/métodos
15.
Molecules ; 29(9)2024 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-38731426

RESUMEN

The use of by-products as a source of bioactive compounds with economic added value is one of the objectives of a circular economy. The olive oil industry is a source of olive pomace as a by-product. The olive pomace used in the present study was the exhausted olive pomace, which is the by-product generated from the air drying and subsequent hexane extraction of residual oil from the olive pomace. The objective was to extract bioactive compounds remaining in this by-product. Various types of green extraction were used in the present study: solvent extraction (water and hydroalcoholic); ultrasound-assisted extraction; Ultra-Turrax-assisted extraction; and enzyme-assisted extraction (cellulase; viscoenzyme). The phenolic profile of each extract was determined using HPLC-DAD and the total phenolic content (TPC) and antioxidant activity (ABTS, DPPH, and ORAC) were determined as well. The results showed significant differences in the yield of extraction among the different methods used, with the enzyme-assisted, with or without ultrasound, extraction presenting the highest values. The ultrasound-assisted hydroethanolic extraction (USAHE) was the method that resulted in the highest content of the identified phenolic compounds: 2.021 ± 0.29 mg hydroxytyrosol/100 mg extract, 0.987 ± 0.09 mg tyrosol/100 mg extract, and 0.121 ± 0.005 mg catechol/100 mg extract. The conventional extraction with water at 50 °C produced the best results for TPC and antioxidant activity of the extracts. The extracts from the USAHE were able to inhibit Gram-positive bacteria, especially Bacillus cereus, showing 67.2% inhibition at 3% extract concentration.


Asunto(s)
Antioxidantes , Aceite de Oliva , Extractos Vegetales , Polifenoles , Aceite de Oliva/química , Polifenoles/aislamiento & purificación , Polifenoles/química , Polifenoles/farmacología , Extractos Vegetales/química , Extractos Vegetales/farmacología , Antioxidantes/química , Antioxidantes/farmacología , Antioxidantes/aislamiento & purificación , Tecnología Química Verde/métodos , Olea/química , Cromatografía Líquida de Alta Presión/métodos , Solventes/química
16.
Molecules ; 29(9)2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38731560

RESUMEN

2, 6-diisopropylaniline (2, 6-DIPA) is a crucial non-intentionally organic additive that allows the assessment of the production processes, formulation qualities, and performance variations in biodegradable mulching film. Moreover, its release into the environment may have certain effects on human health. Hence, this study developed simultaneous heating hydrolysis-extraction and amine switchable hydrophilic solvent vortex-assisted homogeneous liquid-liquid microextraction for the gas chromatography-mass spectrometry analysis of the 2, 6-DIPA additive and its corresponding isocyanates in poly(butylene adipate-co-terephthalate) (PBAT) biodegradable agricultural mulching films. The heating hydrolysis-extraction conditions and factors influencing the efficiency of homogeneous liquid-liquid microextraction, such as the type and volume of amine, homogeneous-phase and phase separation transition pH, and extraction time were investigated and optimized. The optimum heating hydrolysis-extraction conditions were found to be a H2SO4 concentration of 2.5 M, heating temperature of 87.8 °C, and hydrolysis-extraction time of 3.0 h. As a switchable hydrophilic solvent, dipropylamine does not require a dispersant. Vortex assistance is helpful to speed up the extraction. Under the optimum experimental conditions, this method exhibits a better linearity (0.0144~7.200 µg mL-1 with R = 0.9986), low limit of detection and quantification (0.0033 µg g-1 and 0.0103 µg g-1), high extraction recovery (92.5~105.4%), desirable intra- and inter-day precision (relative standard deviation less than 4.1% and 4.7%), and high enrichment factor (90.9). Finally, this method was successfully applied to detect the content of the additive 2, 6-DIPA in PBAT biodegradable agricultural mulching films, thus facilitating production process monitoring or safety assessments.


Asunto(s)
Aminas , Compuestos de Anilina , Cromatografía de Gases y Espectrometría de Masas , Interacciones Hidrofóbicas e Hidrofílicas , Microextracción en Fase Líquida , Solventes , Microextracción en Fase Líquida/métodos , Cromatografía de Gases y Espectrometría de Masas/métodos , Solventes/química , Aminas/química , Aminas/análisis , Compuestos de Anilina/química , Hidrólisis , Poliésteres/química
17.
Molecules ; 29(9)2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38731557

RESUMEN

The supramolecular solvent (SUPRAS) has garnered significant attention as an innovative, efficient, and environmentally friendly solvent for the effective extraction and separation of bioactive compounds from natural resources. However, research on the use of a SUPRAS for the extraction of phenolic compounds from plants, which are highly valued in food products due to their exceptional antioxidant properties, remains scarce. The present study developed a green, ultra-sound-assisted SUPRAS method for the simultaneous determination of three phenolic acids in Prunella vulgaris using high-performance liquid chromatography (HPLC). The experimental parameters were meticulously optimized. The efficiency and antioxidant properties of the phenolic compounds obtained using different extraction methods were also compared. Under optimal conditions, the extraction efficiency of the SUPRAS, prepared with octanoic acid reverse micelles dispersed in ethanol-water, significantly exceeded that of conventional organic solvents. Moreover, the SUPRAS method demonstrated greater antioxidant capacity. Confocal laser scanning microscopy (CLSM) images revealed the spherical droplet structure of the SUPRAS, characterized by a well-defined circular fluorescence position, which coincided with the position of the phenolic acids. The phenolic acids were encapsulated within the SUPRAS droplets, indicating their efficient extraction capacity. Furthermore, molecular dynamics simulations combined with CLSM supported the proposed method's mechanism and theoretically demonstrated the superior extraction performance of the SUPRAS. In contrast to conventional methods, the higher extraction efficiency of the SUPRAS can be attributed to the larger solvent contact surface area, the formation of more types of hydrogen bonds between the extractants and the supramolecular solvents, and stronger, more stable interaction forces. The results of the theoretical studies corroborate the experimental outcomes.


Asunto(s)
Antioxidantes , Fenoles , Extractos Vegetales , Solventes , Solventes/química , Fenoles/química , Fenoles/aislamiento & purificación , Antioxidantes/química , Antioxidantes/aislamiento & purificación , Extractos Vegetales/química , Cromatografía Líquida de Alta Presión/métodos , Tecnología Química Verde , Simulación de Dinámica Molecular , Hidroxibenzoatos/química , Hidroxibenzoatos/aislamiento & purificación
18.
J Chem Inf Model ; 64(9): 3767-3778, 2024 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-38621228

RESUMEN

In this work, we introduce the Solvate Suite, a comprehensive and modular command-line interface designed for molecular simulation and microsolvation modeling. The suite interfaces with widely used scientific software, streamlining computational experiments for liquid systems through the automated creation of simulation boxes and topology with adjustable simulation parameters. Furthermore, it has features for graphical and statistical analysis of simulated properties and extraction of trajectory configurations with various filters. Additionally, it introduces innovative strategies for microsolvation modeling with a multiscale approach, employing equilibrated dynamics to identify favorable solute-solvent interactions and enabling full cluster optimization for free-energy calculations without imaginary frequency contamination.


Asunto(s)
Simulación de Dinámica Molecular , Programas Informáticos , Solventes , Solventes/química , Termodinámica , Interfaz Usuario-Computador
19.
J Chem Inf Model ; 64(9): 3599-3604, 2024 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-38620066

RESUMEN

Understanding tautomerism and characterizing solvent effects on the dynamic processes pose significant challenges. Using enhanced-sampling molecular dynamics based on state-of-the-art deep learning potentials, we investigated the tautomeric equilibria of glycine in water. We observed that the tautomerism between neutral and zwitterionic glycine can occur through both intramolecular and intermolecular proton transfers. The latter proceeds involving a contact anionic-glycine-hydronium ion pair or separate cationic-glycine-hydroxide ion pair. These pathways with comparable barriers contribute almost equally to the reaction flux.


Asunto(s)
Glicina , Simulación de Dinámica Molecular , Solventes , Agua , Glicina/química , Agua/química , Solventes/química , Isomerismo , Protones , Conformación Molecular
20.
Artículo en Inglés | MEDLINE | ID: mdl-38564965

RESUMEN

In the present work, a new microextraction procedure combined with gas chromatography-mass spectrometry has been developed for the analysis of several aliphatic amines from urine sample. The sample preparation method was a continuous homogenous liquid phase microextraction that was based on in-situ preparation of 4-chlorophenol: choline chloride deep eutectic solvent. The deep eutectic solvent was prepared by passing the mixture of related compounds through a syringe barrel filled with exothermic salts (calcium chloride and potassium bromide). The released heat by dissolving the salts and increasing the solution ionic strength assists the formation of the deep eutectic solvent. The influence of various factors on the efficiency of the proposed procedure including salts amount, flow rate, pH, salting-out effect, and extraction solvent volume was studied. The calibration curves were linear broadly over the concentration range of 1.2-250 ng mL-1 with coefficient of determinations ≥0.996. The enrichment factors were in the range of 188-246 and the limits of detection and quantification were 0.16-0.37 and 0.56-1.2 ng mL-1, respectively. Based on the results, the offered method was sensitive, rapid, eco-friendly, and efficient for extracting and determining aliphatic amines in urine samples.


Asunto(s)
Microextracción en Fase Líquida , Solventes/química , Microextracción en Fase Líquida/métodos , Cromatografía de Gases y Espectrometría de Masas/métodos , Disolventes Eutécticos Profundos , Sales (Química) , Colina , Límite de Detección
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