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1.
Food Res Int ; 188: 114498, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38823878

RESUMO

The emulsifying potential of a biocompatible ionic liquid (IL) to produce lipid-based nanosystems developed to enhance the bioaccessibility of cannabidiol (CBD) was investigated. The IL (cholinium oleate) was evaluated at concentrations of 1 % and 2 % to produce nanoemulsions (NE-IL) and nanostructured lipid carriers (NLC-IL) loaded with CBD. The IL concentration of 1 % demonstrated to be sufficient to produce both NE-IL and NLC-IL with excellent stability properties, entrapment efficiency superior to 99 %, and CBD retention rate of 100 % during the storage period evaluated (i.e. 28 days at 25 °C). The in vitro digestion evaluation demonstrated that the NLC-IL provided a higher stability to the CBD, while the NE-IL improved the CBD bioaccessibility, which was mainly related to the composition of the lipid matrices used to obtain each nanosystem. Finally, it was observed that the CBD cytotoxicity was reduced when the compound was entrapped into both nanosystems.


Assuntos
Canabidiol , Emulsificantes , Líquidos Iônicos , Canabidiol/química , Líquidos Iônicos/química , Líquidos Iônicos/toxicidade , Emulsificantes/química , Humanos , Emulsões , Digestão , Nanoestruturas/química , Sobrevivência Celular/efeitos dos fármacos , Disponibilidade Biológica , Nanopartículas/química , Portadores de Fármacos/química , Células CACO-2 , Tamanho da Partícula
2.
Mikrochim Acta ; 191(6): 344, 2024 05 27.
Artigo em Inglês | MEDLINE | ID: mdl-38802523

RESUMO

A molecularly imprinted electrochemiluminescent sensor is developed for the sensitive detection of tetracycline in environmental and food samples. The sensor uses an ionic liquid (i.e. [APMIM]Br) modified graphene-carbon nanotube composite (GMI) material as substrate, a double-layered core-shell metal-organic framework NH2-UiO-66@ZIF-8 (NUZ) loaded bipyridyl ruthenium (NUZ@Ru) as luminescent material, and a molecularly imprinted copolymer of o-phenylenediamine and hydroquinone as recognition element. The ionic liquid-modified graphene-carbon nanotube composite has a favorable three-dimensional structure, high specific surface area, and good hydrophilicity; the core-shell structured metal-organic framework has high stability and plentiful reaction sites for loading; the molecularly imprinted copolymer film has enhanced stability and recognition effect. Hence, the resulting sensor combines the merits of several materials and presents improved performance. Under the optimum detection conditions, it shows a wide linear range of 0.05 µM - 1 mM, a low detection limit of 20 nM, high selectivity, and excellent stability. It has been successfully applied to the detection of tetracycline in different samples.


Assuntos
Técnicas Eletroquímicas , Limite de Detecção , Medições Luminescentes , Estruturas Metalorgânicas , Polímeros Molecularmente Impressos , Tetraciclina , Tetraciclina/análise , Tetraciclina/química , Polímeros Molecularmente Impressos/química , Estruturas Metalorgânicas/química , Medições Luminescentes/métodos , Técnicas Eletroquímicas/métodos , Grafite/química , Nanotubos de Carbono/química , Contaminação de Alimentos/análise , Líquidos Iônicos/química , Antibacterianos/análise , Antibacterianos/química , Poluentes Químicos da Água/análise , Impressão Molecular
3.
Int J Biol Macromol ; 268(Pt 2): 131997, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38697420

RESUMO

Hybrid ionic fluids (HIFs) are one of the emerging and fascinating sustainable solvent media, a novel environment-friendly solvent for biomolecules. The HIFs have been synthesized by combining a deep eutectic solvent (DES), an ionic liquid (IL) having a common ion. The stability and activity of hen's egg white lysozyme (Lyz) in the presence of a recently designed new class of biocompatible solvents, HIFs have been explored by UV-visible, steady-state fluorescence, circular dichroism (CD), Fourier transform infrared spectroscopy (FT-IR) along with dynamic light scattering (DLS) measurements. This work emphasizes the effect of DES synthesized by using 1:2 choline chloride and glycerol [Glyn], ILs (1-butly-3-methylimidazolium chloride [BMIM]Cl and choline acetate [Chn][Ac]) and their corresponding HIFs on the structure and functionality of Lyz. Moving forward, we also studied the secondary structure, thermal stability and enzymatic activity and thermodynamic profile of Lyz at pH = 7 in the presence of varying concentrations (0.1 to 0.5) M of [BMIM]Cl, [Chn][Ac] ILs, [Glyn] DES and [Glyn][BMIM]Cl (hybrid ionic fluid1) as well as [Glyn][Chn][Ac] (hybrid ionic fluid2). Spectroscopic results elucidate that ILs affect the activity and structural stability of Lyz, whereas the stability and activity are increased by DES and are maintained by HIFs at all the studied concentrations. Overall, the experimental results studied elucidate expressly that the properties of Lyz are maintained in the presence of hybrid ionic fluid1 while these properties are intensified in hybrid ionic fluid2. This work has elucidated expressly biocompatible green solvents in protein stability and functionality due to the alluring properties of DES, which can counteract the negative effect of ILs in HIFs.


Assuntos
Líquidos Iônicos , Muramidase , Líquidos Iônicos/química , Muramidase/química , Solventes Eutéticos Profundos/química , Estabilidade Enzimática , Animais , Colina/química , Termodinâmica , Imidazóis/química , Glicerol/química , Solventes/química , Estrutura Secundária de Proteína , Concentração de Íons de Hidrogênio
4.
J Am Chem Soc ; 146(19): 13588-13597, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38695646

RESUMO

Membrane channel proteins (MCPs) play key roles in matter transport through cell membranes and act as major targets for vaccines and drugs. For emerging ionic liquid (IL) drugs, a rational understanding of how ILs affect the structure and transport function of MCP is crucial to their design. In this work, GPU-accelerated microsecond-long molecular dynamics simulations were employed to investigate the modulating mechanism of ILs on MCP. Interestingly, ILs prefer to insert into the lipid bilayer and channel of aquaporin-2 (AQP2) but adsorb on the entrance of voltage-gated sodium channels (Nav). Molecular trajectory and free energy analysis reflect that ILs have a minimal impact on the structure of MCPs but significantly influence MCP functions. It demonstrates that ILs can decrease the overall energy barrier for water through AQP2 by 1.88 kcal/mol, whereas that for Na+ through Nav is increased by 1.70 kcal/mol. Consequently, the permeation rates of water and Na+ can be enhanced and reduced by at least 1 order of magnitude, respectively. Furthermore, an abnormal IL gating mechanism was proposed by combining the hydrophobic nature of MCP and confined water/ion coordination effects. More importantly, we performed experiments to confirm the influence of ILs on AQP2 in human cells and found that treatment with ILs significantly accelerated the changes in cell volume in response to altered external osmotic pressure. Overall, these quantitative results will not only deepen the understanding of IL-cell interactions but may also shed light on the rational design of drugs and disease diagnosis.


Assuntos
Líquidos Iônicos , Simulação de Dinâmica Molecular , Líquidos Iônicos/química , Líquidos Iônicos/farmacologia , Humanos , Aquaporina 2/metabolismo , Aquaporina 2/química , Água/química , Bicamadas Lipídicas/química , Bicamadas Lipídicas/metabolismo , Sódio/química , Sódio/metabolismo
5.
Int J Mol Sci ; 25(9)2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38731923

RESUMO

Ionic liquids (ILs) have gained considerable attention due to their versatile and designable properties. ILs show great potential as antibacterial agents, but understanding the mechanism of attack on bacterial cells is essential to ensure the optimal design of IL-based biocides. The final aim is to achieve maximum efficacy while minimising toxicity and preventing resistance development in target organisms. In this study, we examined a dose-response analysis of ILs' antimicrobial activity against two pathogenic bacteria with different Gram types in terms of molecular responses on a cellular level using Fourier-transform infrared (FTIR) spectroscopy. In total, 18 ILs with different antimicrobial active motifs were evaluated on the Gram-negative enteropathogenic Escherichia coli (EPEC) and Gram-positive methicillin-resistant Staphylococcus aureus (MRSA). The results showed that most ILs impact bacterial proteins with increasing concentration but have a minimal effect on cellular membranes. Dose-response spectral analysis revealed a distinct ante-mortem response against certain ILs for MRSA but not for EPEC. We found that at sub-lethal concentrations, MRSA actively changed their membrane composition to counteract the damaging effect induced by the ILs. This suggests a new adaptive mechanism of Gram-positive bacteria against ILs and demonstrates the need for a better understanding before using such substances as novel antimicrobials.


Assuntos
Escherichia coli Enteropatogênica , Líquidos Iônicos , Staphylococcus aureus Resistente à Meticilina , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Líquidos Iônicos/química , Líquidos Iônicos/farmacologia , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Escherichia coli Enteropatogênica/efeitos dos fármacos , Antibacterianos/farmacologia , Antibacterianos/química , Testes de Sensibilidade Microbiana
6.
Phys Chem Chem Phys ; 26(20): 14766-14776, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38716816

RESUMO

Hybrid ionic fluids (HIFs) are newly emerging and fascinating sustainable solvent media, which are attracting a great deal of scientific interest in protecting the native structure of proteins. For a few decades, there has been a demand to consider ionic liquids (ILs) and deep eutectic solvents (DESs) as biocompatible solvent media for enzymes; however, in some cases, these solvent media also show limitations. Therefore, this work focuses on synthesising novel HIFs to intensify the properties of existing ILs and DESs by mixing them. Herein, HIFs have been synthesised by the amalgamation of a deep eutectic solvent (DES) and an ionic liquid (IL) with a common cation or anion. Later on, the stability and activity of hen's egg white lysozyme (Lyz) in the presence of biocompatible solvent media and HIFs were studied by various techniques such as UV-vis, steady-state fluorescence, circular dichroism (CD), Fourier transform infrared spectroscopy (FT-IR) and dynamic light scattering (DLS) measurements. This work emphasises the effect of a DES (synthesised using 1 : 2 choline chloride and malonic acid) [Maline], ILs (1-butyl-3-methylimidazolium chloride [BMIM]Cl or choline acetate [Chn][Ac]) and their corresponding HIFs on the structure and functionality of Lyz. Moreover, we also studied the secondary structure, thermal stability, enzymatic activity and thermodynamic profile of Lyz at pH = 7 in the presence of varying concentrations (0.1 to 0.5 M) of [BMIM]Cl and [Chn][Ac] ILs, Maline as a DES, and Maline [BMIM]Cl (HIF1) and Maline [Chn][Ac] (HIF2). Spectroscopic results elucidate that ILs affect the activity and structural stability of Lyz. In contrast, the stability and activity are inhibited by DES and are enhanced by HIFs at all the studied concentrations. Overall, the experimental results studied explicitly elucidate that the structure and stability of Lyz are maintained in the presence of HIF1 while these properties are intensified in HIF2. This study shows various applications in biocompatible green solvents, particularly in the stability and functionality of proteins, due to their unique combination where the properties counteract the negative effect of either DESs or ILs in HIFs.


Assuntos
Solventes Eutéticos Profundos , Estabilidade Enzimática , Líquidos Iônicos , Muramidase , Líquidos Iônicos/química , Muramidase/química , Muramidase/metabolismo , Solventes Eutéticos Profundos/química , Solventes/química , Animais , Galinhas , Colina/química
7.
J Am Chem Soc ; 146(20): 13903-13913, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38721817

RESUMO

Cohesive and interfacial adhesion energies are difficult to balance to obtain reversible adhesives with both high mechanical strength and high adhesion strength, although various methods have been extensively investigated. Here, a biocompatible citric acid/L-(-)-carnitine (CAC)-based ionic liquid was developed as a solvent to prepare tough and high adhesion strength ionogels for reversible engineered and biological adhesives. The prepared ionogels exhibited good mechanical properties, including tensile strength (14.4 MPa), Young's modulus (48.1 MPa), toughness (115.2 MJ m-3), and high adhesion strength on the glass substrate (24.4 MPa). Furthermore, the ionogels can form mechanically matched tough adhesion at the interface of wet biological tissues (interfacial toughness about 191 J m-2) and can be detached by saline solution on demand, thus extending potential applications in various clinical scenarios such as wound adhesion and nondestructive transfer of organs.


Assuntos
Materiais Biocompatíveis , Ácido Cítrico , Géis , Materiais Biocompatíveis/química , Materiais Biocompatíveis/síntese química , Ácido Cítrico/química , Géis/química , Carnitina/química , Líquidos Iônicos/química , Resistência à Tração , Adesivos/química
8.
Food Chem ; 453: 139677, 2024 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-38788647

RESUMO

Perfluoroalkyl acids (PFAAs) are emerging pollutants that endangers food safety. Developing methods for the selective determination of trace PFAAs in complex samples remains challenging. Herein, an ionic liquid modified porous imprinted phenolic resin-dispersive filter extraction-liquid chromatography-tandem mass spectrometry (IL-PIPR-DFE-LC-MS/MS) method was developed for the determination of perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS) in eggs. The new IL-PIPR adsorbent was prepared at room temperature, which avoids the disorder and instability of the template at high temperatures. The imprinting factor of IL-PIPR for PFOA and PFOS exceeded 7.3. DFE, combined with IL-PIPR (15 mg), was used to extract PFOA and PFOS from eggs within 15 min. The established method exhibits low limits of detection (0.01-0.02 ng/g) and high recoveries (84.7%-104.7%), which surpass those of previously reported methods. This work offers a new approach to explore advanced imprinted adsorbents for PFAAs, efficient sample pretreatment technique, and analytical method for pollutants in foods.


Assuntos
Ovos , Fluorocarbonos , Contaminação de Alimentos , Líquidos Iônicos , Impressão Molecular , Espectrometria de Massas em Tandem , Fluorocarbonos/isolamento & purificação , Fluorocarbonos/análise , Fluorocarbonos/química , Ovos/análise , Contaminação de Alimentos/análise , Líquidos Iônicos/química , Ácidos Alcanossulfônicos/análise , Ácidos Alcanossulfônicos/isolamento & purificação , Ácidos Alcanossulfônicos/química , Caprilatos/química , Caprilatos/análise , Caprilatos/isolamento & purificação , Adsorção , Animais , Extração em Fase Sólida/métodos , Extração em Fase Sólida/instrumentação , Galinhas
9.
Chem Biol Interact ; 396: 111042, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38735455

RESUMO

Ionic liquids (ILs) are a class of low melting point salts with physicochemical properties suitable for a range of industrial applications such as chemical processing and battery design. Major challenges to the wide-scale adoption of ILs in industry include their eco- and cytotoxic effects, however, this opens up the possibility of the use of ILs use as novel anticancer agents. Understanding the structural features that promote IL cytotoxicity is therefore important. Key structural features that can impact IL cytotoxicity include size and lipophilicity of the cationic head group. In this study, the cytotoxic effects of acridinium-based ILs containing relatively large tri- and tetracyclic cations were evaluated. It was found that 9-phenylacridinium-based ILs are potent cytotoxic agents that reduce the viability of human MDA-MB-231 breast cancer cells with IC50 concentrations in the nanomolar range. In mechanistic studies, it was found that unlike the pyridinium-based analogue, [C16Py][I], acridinium-based ILs did not inhibit oxidative phosphorylation or induce reactive oxygen species formation, and may instead target other mitochondrial processes or components such as mitochondrial DNA.


Assuntos
Acridinas , Líquidos Iônicos , Espécies Reativas de Oxigênio , Humanos , Líquidos Iônicos/química , Líquidos Iônicos/farmacologia , Acridinas/química , Acridinas/farmacologia , Relação Estrutura-Atividade , Linhagem Celular Tumoral , Espécies Reativas de Oxigênio/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Antineoplásicos/farmacologia , Antineoplásicos/química , Fosforilação Oxidativa/efeitos dos fármacos
10.
Bioresour Technol ; 402: 130803, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38734263

RESUMO

An ionic liquid (IL, [DMAPA]HSO4) was prepared to facilitate the removal of heavy metals by hydrothermal carbonization (HTC) in sewage sludge (SS) and to obtain a positive energy recovery (ER, (Energyoutput/Energyinput - 1) > 0). The results found that the removal efficiencies of the Fe, Mn, Zn, Co, and Cd from SS exceeded 75 % with positive ER (6 %) at 20 wt% IL dosage (IL:SS). IL promoted the HTC reactions of proteins and polysaccharides to produce fixed carbon and small molecule polymers. The process mainly relies on IL to catalyze the dehydration and graphitization of SS and to destroy the heavy metal binding sites such as carboxyl and hydroxyl groups. Additionally, IL aids in constructing the macropore structures in hydrochar, thereby facilitating the release of heavy metals and water during the HTC process. This discovery holds promise for removing heavy metals from SS by one-pot HTC processes with positive energy recovery.


Assuntos
Líquidos Iônicos , Metais Pesados , Esgotos , Metais Pesados/química , Esgotos/química , Líquidos Iônicos/química , Catálise , Carbono/química , Carvão Vegetal/química , Poluentes Químicos da Água , Temperatura , Purificação da Água/métodos , Temperatura Baixa
11.
Food Chem ; 451: 139521, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38703735

RESUMO

This study explored the use of ionic liquid-ultrasound (ILU)-assisted extraction to enhance the extraction rate of Platycodon grandiflorum saponins (PGSs), and the content, extraction mechanism, antioxidant activity, whitening, and antiaging activity of PGSs prepared using ILU, ultrasound-water, thermal reflux-ethanol, and cellulase hydrolysis were compared. The ILU method particularly disrupted the cell wall, improved PGS extraction efficiency, and yielded a high total saponin content of 1.45 ± 0.02 mg/g. Five monomeric saponins were identified, with platycodin D being the most abundant at 1.357 mg/g. PGSs displayed excellent in vitro antioxidant activity and exhibited inhibitory effects on tyrosinase, elastase, and hyaluronidase. The results suggest that PGSs may have broad antioxidant, skin-whitening, and antiaging potential to a large extent. Overall, this study provided valuable insights into the extraction, identification, and bioactivities of PGSs, which could serve as a reference for future development and application of these compounds in the functional foods industry.


Assuntos
Antioxidantes , Líquidos Iônicos , Extratos Vegetais , Platycodon , Saponinas , Antioxidantes/química , Antioxidantes/farmacologia , Antioxidantes/isolamento & purificação , Saponinas/farmacologia , Saponinas/química , Saponinas/isolamento & purificação , Platycodon/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Extratos Vegetais/isolamento & purificação , Líquidos Iônicos/química , Envelhecimento da Pele/efeitos dos fármacos , Humanos , Ondas Ultrassônicas
12.
Molecules ; 29(10)2024 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-38792242

RESUMO

The development of immobilized enzymes with high activity and stability is critical. Metal-organic frameworks (MOFs) have attracted much academic and industrial interest in the field of enzyme immobilization due to their unique properties. In this study, the amino-functionalized ionic liquid (NIL)-modified metal-organic framework (UiO-66-NH2) was prepared to immobilize Candida rugosa lipase (CRL), using dialdehyde starch (DAS) as the cross-linker. The results of the Fourier transform infrared (FT-IR) spectra, X-ray powder diffraction (XRD), and scanning electronic microscopy (SEM) confirmed that the NIL was successfully grafted to UiO-66-NH2. The CRL immobilized on NIL-modified UiO-66-NH2 (UiO-66-NH2-NIL-DAS@CRL) exhibited satisfactory activity recovery (79.33%), stability, reusability, and excellent organic solvent tolerance. The research results indicated that ionic liquid-modified UiO-66-NH2 had practical potential for application in enzyme immobilization.


Assuntos
Enzimas Imobilizadas , Líquidos Iônicos , Lipase , Estruturas Metalorgânicas , Lipase/química , Lipase/metabolismo , Líquidos Iônicos/química , Enzimas Imobilizadas/química , Estruturas Metalorgânicas/química , Estabilidade Enzimática , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X , Amido/química , Amido/análogos & derivados , Saccharomycetales/enzimologia , Ácidos Ftálicos
13.
Environ Sci Pollut Res Int ; 31(24): 35553-35566, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38733444

RESUMO

Volatile organic compounds (VOCs) frequently pose a threat to the biosphere, impacting ecosystems, flora, fauna, and the surrounding environment. Industrial emissions of VOCs often include the presence of water vapor, which, in turn, diminishes the adsorption capacity and efficacy of adsorbents. This occurs due to the competitive adsorption of water vapor, which competes with target pollutants for adsorption sites on the adsorbent material. In this study, hydrophobic activated carbons (BMIMPF6-AC (L), BMIMPF6-AC (g), and BMIMPF6-AC-H) were successfully prepared using 1-butyl-3-methylimidazolium hexafluorophosphate (BMIMPF6) to adsorb toluene under humidity environment. The adsorption performance and mechanism of the resulting ionic liquid-modified activated carbon for toluene in a high-humidity environment were evaluated to explore the potential application of ionic liquids as hydrophobic modifiers. The results indicated that BMIMPF6-AC-H exhibited superior hydrophobicity. The toluene adsorption capacity of BMIMPF6-AC-H was 1.53 times higher than that of original activated carbon, while the adsorption capacity for water vapor was only 37.30% of it at 27 °C and 77% RH. The Y-N model well-fitted the dynamic adsorption experiments. To elucidate the microscopic mechanism of hydrophobic modification, the Independent Gradient Model (IGM) method was employed to characterize the intermolecular interactions between BMIMPF6 and toluene. Overall, this study introduces a new modifier for hydrophobic modification of activated carbon, which could enhance the efficiency of activated carbon in treating industrial VOCs.


Assuntos
Umidade , Líquidos Iônicos , Tolueno , Compostos Orgânicos Voláteis , Líquidos Iônicos/química , Adsorção , Tolueno/química , Compostos Orgânicos Voláteis/química , Carvão Vegetal/química , Poluentes Atmosféricos/química , Interações Hidrofóbicas e Hidrofílicas , Imidazóis/química
14.
J Phys Chem B ; 128(22): 5407-5418, 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38795045

RESUMO

In this work, we explored how the amount of cholesterol in the lipid membrane composed of phosphatidylcholine (POPC) or phosphatidylglycerol (POPG) affects the interaction with 1-dodecyl-3-methylimidazolium bromide ([C12MIM]+Br-) ionic liquids using various biophysical techniques. On interacting with the membrane, [C12MIM]+Br- leads to enhanced membrane permeability and induces membrane fusion, leading to an increase in vesicle size. The 2H-based solid-state NMR investigations of cholesterol-containing lipid membranes reveal that [C12MIM]+Br- decreases the lipid chain order parameters and counteracts the lipid condensation effect of cholesterol to some extent. Therefore, as the amount of cholesterol in the membrane increases, the membrane effect of [C12MIM]+Br- decreases. The effect of [C12MIM]+Br- on the membrane properties is more pronounced for POPC compared to that of POPG membranes. This suggests a dependence of these effects on the electrostatic interactions, indicating that the influence of [C12MIM]+Br- varies based on the lipid composition. The findings suggest that the presence of cholesterol can modulate the effect of [C12MIM]+Br- on membrane properties, with variations observed between POPC and POPG membranes, highlighting the importance of lipid composition. In short, this study provides insights into the intricate interplay between cholesterol, the lipid membrane, and the ionic liquid [C12MIM]+Br-.


Assuntos
Colesterol , Imidazóis , Líquidos Iônicos , Fosfatidilcolinas , Fosfatidilgliceróis , Líquidos Iônicos/química , Colesterol/química , Colesterol/metabolismo , Fosfatidilgliceróis/química , Fosfatidilcolinas/química , Imidazóis/química , Permeabilidade , Bicamadas Lipídicas/química , Bicamadas Lipídicas/metabolismo
15.
Phys Chem Chem Phys ; 26(22): 16218-16233, 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38804505

RESUMO

The micellization of choline-based anionic surface-active ionic liquids (SAILs) having lauroyl sarcosinate [Sar]-, dodecylsulfate [DS]-, and deoxycholate [Doc]- as counter-ions was investigated in an aqueous medium. Density functional theory (DFT) was employed to investigate the net interactional energy (Enet), extent of non-covalent interactions, and band gap of the choline-based SAILs. The critical micelle concentration (cmc) along with various parameters related to the surface adsorption, counter-ion binding (ß), and polarity of the cores of the micelles were deduced employing surface tension measurements, conductometric titrations and fluorescence spectroscopy, respectively. A dynamic light scattering (DLS) system equipped with zeta-potential measurement set-up and small-angle neutron scattering (SANS) were used to predict the size, zeta-potential, and morphology, respectively, of the formed micelles. Thermodynamic parameters such as standard Gibb's free energy and standard enthalpy change of micellization were calculated using isothermal titration calorimetry (ITC). Upon comparing with sodium salt analogues, it was established that the micellization was predominantly governed by the extent of hydration of [Cho]+, the head groups of the respective anions, and the degree of counter-ion binding (ß). Considering the concentration dependence of the enzyme-SAIL interactions, aqueous solutions of the synthesized SAILs at two different concentrations (below and above the cmc) were utilized as the medium for testing the enzymatic activity of cellulase. The activity of cellulase was found to be ∼7- to ∼13-fold higher compared to that observed in buffers in monomeric solutions of the SAILs and followed the order: [Cho][Sar] > [Cho][DS] > [Cho][Doc]. In the micellar solution, a ∼4- to 5-fold increase in enzymatic activity was observed.


Assuntos
Celulase , Colina , Líquidos Iônicos , Micelas , Água , Líquidos Iônicos/química , Colina/química , Colina/análogos & derivados , Celulase/química , Celulase/metabolismo , Água/química , Termodinâmica , Tensoativos/química , Teoria da Densidade Funcional
16.
J Environ Manage ; 360: 121195, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38761622

RESUMO

The carbonization of lignocellulosic biomass with ionic liquids (ILs) are considered as an advantageous approach for the preparation of carbonaceous materials. The commonly used imidazolium and pyridinium based ILs have drawbacks such as toxicity, resistance to biodegradation, high cost and viscosity. These issues can be mitigated by diluting ILs with water, although excessive water content above 1 wt% can reduce the solubility of biomass. This research aims to investigate the potential of pretreating wastepaper with a "fully green" ILs, amino acid-based IL with high water content, followed by pyrolysis without IL, in enhancing the properties of biochar. For this purpose, the paper was treated with an aqueous solution of IL cysteine nitrate ([Cys][NO3]), and the IL was not involved in the pyrolysis process to prevent the formation of secondary gaseous pollutants. The findings revealed that the hemicellulose and mineral filler in the paper were eliminated during pretreatment, leading to higher carbon content but lower oxygen content. As a result, the biochar exhibited micropores of 0.42 cm3g-1 and a specific surface area of 1011.21 m2 g-1. The biochar demonstrated high adsorption capacities for Cd2+, enrofloxacin, bisphenol A, ciprofloxacin, and tetracycline, with values of 45.20 mg g-1, 49.82 mg g-1, 49.90 mg g-1, 49.88 mg g-1, and 49.65 mg g-1, respectively. The proposed mechanism for the adsorption of enrofloxacin by the biochar primarily involves physical adsorption such as pore filling and electrostatic interactions, along with chemical adsorption facilitated by graphitic nitrogen.


Assuntos
Aminoácidos , Carvão Vegetal , Líquidos Iônicos , Líquidos Iônicos/química , Carvão Vegetal/química , Adsorção , Aminoácidos/química
17.
J Am Chem Soc ; 146(19): 13247-13257, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38701006

RESUMO

Horseradish peroxidase (HRP) is an enzyme that oxidizes pollutants from wastewater. A previous report indicated that peroxidases can have an enhancement in initial enzymatic activity in an aqueous solution of 0.26 M 1-ethyl-3-methylimidazolium ethyl sulfate ([EMIm][EtSO4]) at neutral pH. However, the atomistic details remain elusive. In the enzymatic landscape of HRP, compound II (Cpd II) plays a key role and involves a histidine (H42) residue. Cpd II exists as oxoferryl (2a) or hydroxoferryl (2b(FeIV)) forms, where 2a is the predominantly observed form in experimental studies. Intriguingly, the ferric 2b(FeIII) form seen in synthetic complexes has not been observed in HRP. Here, we have investigated the structure and dynamics of HRP in pure water and aqueous [EMIm][EtSO4] (0.26 M), as well as the reaction mechanism of 2a to 2b conversion using polarizable molecular dynamics (MD) simulations and quantum mechanics/molecular mechanics (QM/MM) calculations. When HRP is solvated in aq [EMIm][EtSO4], the catalytic water displaces, and H42 directly orients over the ferryl moiety, allowing a direct proton transfer (PT) with a significant energy barrier reduction. Conversely, in neat water, the reaction of 2a to 2b follows the previously reported mechanism. We further investigated the deprotonated form of H42. Analysis of the electric fields at the active site indicates that the aq [EMIm][EtSO4] medium facilitates the reaction by providing a more favorable environment compared with the system solvated in neat water. Overall, the atomic level supports the previous experimental observations and underscores the importance of favorable electric fields in the active site to promote catalysis.


Assuntos
Peroxidase do Rábano Silvestre , Líquidos Iônicos , Simulação de Dinâmica Molecular , Peroxidase do Rábano Silvestre/química , Peroxidase do Rábano Silvestre/metabolismo , Líquidos Iônicos/química , Imidazóis/química , Teoria Quântica , Soluções , Água/química
18.
Int J Biol Macromol ; 270(Pt 1): 132208, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38723835

RESUMO

Monoclonal antibodies (mAbs) have revolutionised the biopharmaceutical market. Being proteinaceous, mAbs are prone to chemical and physical instabilities. Various approaches were attempted to stabilise proteins against degradation factors. Ionic liquids (ILs) and deep eutectic solvents (DESs) have been established as green solvents for ever-increasing pharmaceutical and biopharmaceutical applications. Hence, amino acid (AA)-based ILs, were used for the first time, for mAb stabilisation. Choline (Ch)-based DESs were also utilised for comparison purposes. The prepared ILs and DESs were utilised to stabilise Atezolizumab (Amab, anti-PDL-1 mAb). The formulations of Amab in ILs and DESs were incubated at room temperature, 45 or 55 °C. Following this, the structural stability of Amab was appraised. Interestingly, Ch-Valine retained favourable structural stability of Amab with minimal detected aggregation or degradation as confirmed by UV-visible spectroscopy and protein Mass Spectroscopy. The measured hydrodynamic diameter of Amab in Ch-Valine ranged from 10.40 to 11.65 nm. More interestingly, the anticancer activity of Amab was evaluated, and Ch-Valine was found to be optimum in retaining the activity of Amab when compared to other formulations, including the control Amab sample. Collectively, this study has spotlighted the advantages of adopting the Ch-AA ILs for the structural and functional stabilising of mAbs.


Assuntos
Aminoácidos , Anticorpos Monoclonais Humanizados , Antineoplásicos , Líquidos Iônicos , Líquidos Iônicos/química , Anticorpos Monoclonais Humanizados/química , Anticorpos Monoclonais Humanizados/farmacologia , Humanos , Antineoplásicos/química , Antineoplásicos/farmacologia , Aminoácidos/química , Coloides/química , Estabilidade de Medicamentos , Anticorpos Monoclonais/química , Anticorpos Monoclonais/farmacologia , Estabilidade Proteica , Temperatura , Linhagem Celular Tumoral , Solventes/química
19.
Int J Biol Macromol ; 270(Pt 1): 132149, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38740158

RESUMO

In recent years, the process of producing bioethanol from lignocellulosic biomass through biorefining has become increasingly important. However, to obtain a high yield of ethanol, the complex structures in the feedstock must be broken down into simple sugars. A cost-effective and innovative method for achieving this is ionic liquid pre-treatment, which is widely used to efficiently hydrolyze the lignocellulosic material. The study aims to produce a significant profusion of bioethanol via catalytic hydrolysis of ionic liquid-treated lignocellulose biomass. The current study reports the purification of Streptomyces sp. MS2A cellulase via ultrafiltration and gel permeation chromatography. The kinetic parameters and the biochemical nature of the purified cellulase were analyzed for the effective breakdown of the EMIM[OAC] treated lignocellulose chain. The two-step cellulase purification resulted in 6.28 and 12.44 purification folds. The purified cellulase shows a Km value of 0.82 ± 0.21 mM, and a Vmax value of 85.59 ± 8.87 µmol min-1 mg-1 with the catalytic efficiency of 1.027 S-1. The thermodynamic parameters like ΔH, ΔS, and ΔG of the system were studied along with the thermal deactivation kinetics of cellulase. The optimal temperature and pH of the purified cellulase enzyme for hydrolysis was found to be 40 °C and 7. The rice husk and wheat husk used in this study were pretreated with the EMIM [OAC] ionic liquid and the change in the structure of lignocellulosic biomass was observed via HRSEM. The ionic liquid treated biomass showed the highest catalytic hydrolysis yield of 106.66 ± 0.19 mol/ml on the third day. The obtained glucose was fermented with Saccharomyces cerevisiae to yield 23.43 g of ethanol/l of glucose from the rice husk (RH) and 24.28 g of ethanol/l of glucose from the wheat husk (WH).


Assuntos
Biomassa , Celulase , Etanol , Líquidos Iônicos , Lignina , Streptomyces , Lignina/química , Líquidos Iônicos/química , Celulase/química , Celulase/metabolismo , Etanol/química , Streptomyces/enzimologia , Hidrólise , Cinética , Concentração de Íons de Hidrogênio , Oryza/química , Temperatura , Fermentação , Biocombustíveis
20.
Sci Rep ; 14(1): 11573, 2024 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-38773172

RESUMO

GSK2838232 (GSK8232) is a second-generation maturation inhibitor (MI) developed for the treatment of HIV with excellent broad-spectrum virological profiles. The compound has demonstrated promising clinical results as an orally administered agent. Additionally, the compound's physical and pharmacological properties present opportunities for exploitation as long-acting parenteral formulations. Despite unique design constraints including solubility and dose of GSK8232, we report on three effective tunable drug delivery strategies: active pharmaceutical ingredient (API) suspensions, ionic liquids, and subdermal implants. Promising sustained drug release profiles were achieved in rats with each approach. Additionally, we were able to tune drug release rates through a combination of passive and active strategies, broadening applicability of these formulation approaches beyond GSK8232. Taken together, this report is an important first step to advance long-acting formulation development for critical HIV medicines that do not fit the traditional profile of suitable long-acting candidates.


Assuntos
Liberação Controlada de Fármacos , Animais , Ratos , Interações Hidrofóbicas e Hidrofílicas , Preparações de Ação Retardada , Fármacos Anti-HIV/administração & dosagem , Fármacos Anti-HIV/química , Fármacos Anti-HIV/farmacologia , Fármacos Anti-HIV/farmacocinética , Sistemas de Liberação de Medicamentos/métodos , Líquidos Iônicos/química , Ratos Sprague-Dawley , Masculino , Solubilidade , Infecções por HIV/tratamento farmacológico , Antirretrovirais/administração & dosagem , Antirretrovirais/química
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