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1.
J Magn Reson ; 361: 107666, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38537481

RESUMEN

In situ NMR is a valuable tool for studying electrochemical devices, including redox flow batteries and electrocatalytic reactors, capable of detecting reaction intermediates, metastable states, time evolution of processes or monitoring stability as a function of electrochemical conditions. Here we report a parallel line detector for spatially selective in situ electrochemical NMR spectroscopy. The detector consists of 17 copper wires and is doubly tuned to 1H/19F and X nuclei ranging from 63Cu (106.1 MHz) to 7Li (155.5 MHz). The flat geometry of the parallel line detector allows its insertion into a high electrode surface-to-volume electrochemical flow reactor, enabling a detector-in-a-reactor design. This integrated device is named "eReactor NMR probe". Combined with B1-selective pulse sequences, selective detection of the nuclei at the electrode-electrolyte interface, that is within a distance of 800 µm from the electrode surface, has been achieved. The selective detection of 7Li and 19F nuclei is demonstrated using two electrolytes, LiCl and LiBF4 solutions, respectively. A good B1 homogeneity with an 810° to 90° pulse intensity ratio of 68-72 % was achieved. Using electrochemical plating of lithium metal as a model reaction, we further demonstrated the operando functionality of the probe. The new eReactor NMR probe offers a general method for studying flow electrochemistry, and we envision applications in a wide range of environmentally relevant energy systems, for example, Li metal batteries, electrochemical ammonia synthesis, carbon dioxide capture and reduction, redox flow batteries, fuel cells, water desalination, lignin oxidation etc.

2.
Sci Rep ; 14(1): 13904, 2024 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-38886469

RESUMEN

Prussian Blue Analogues (PBAs), which are characterized by their open structure, high stability, and non-toxic properties, have recently been the subject of research for various applications, including their use as electrode precursors for capacitive deionization, gas storage, and environmental purification. These materials can be readily tailored to enhance their affinity towards gases for integration with sensing devices. An improved understanding of PBA-gas interactions is expected to enhance material development and existing sensor deposition schemes greatly. The use of inverse gas chromatography (IGC) is a robust approach for examining the relationship between porous materials and gases. In this study, the adsorption properties of (functionalized) hydrocarbons, i.e., probe molecules, on the copper hexacyanoferrate (CuHCF) lattice were studied via IGC, demonstrating that alkylbenzenes have a higher affinity for this material than n-alkanes. This difference was rationalized by steric hindrance, π-π interactions, and vapour pressure effects. Along the same line, the five isomers of hexane showed decreasing selectivity upon increased steric hindrance. Enthalpy values for n-pentane, n-hexane and n-heptane were lower than that of toluene. The introduction of increased probe masses resulted in a surface coverage of 46% for toluene. For all n-alkane probe molecules this percentage was lower. However, the isotherms of these probes did not show saturation points and the observed linear regime proves beneficial for gas sensing. Our work demonstrates the versatility of CuHCF for gas sensing purposes and the potential of IGC to characterize the adsorption characteristics of such a porous nanomaterial.

3.
Food Chem ; 440: 138187, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38134831

RESUMEN

Δ8-Tetrahydrocannabinol (Δ8-THC) is increasingly popular as a controversial substitute for Δ9-tetrahydrocannabinol (Δ9-THC) in cannabinoid-infused edibles. Δ8-THC is prepared from cannabidiol (CBD) by treatment with acids. Side products including Δ9-THC and other isomers that might end up in Δ8-THC edibles are less studied. In this paper, three orthogonal methods, namely reversed-phase (RP)-UHPLC-DAD/HRMS, normal-phase/argentation (silica-Ag(I))-HPLC-DAD/MS, and GC-FID/MS were developed for analysis of cannabinoid isomers, namely Δ8-THC, Δ9-THC, CBD, Δ8-iso-THC, Δ(4)8-iso-THC, and hydrated THC isomers. Eight acid-treated CBD mixtures contained various amounts of Δ8-THC (0-89%, w/w%), high levels of Δ9-THC (up to 49%), Δ8-isoTHC (up to 55%), Δ(4)8-iso-THC (up to 17%), and three hydrated THC isomers. Commercial Δ8-THC gummies were also analyzed, and issues like overclaimed Δ8-THC, excessive Δ9-THC, undeclared Δ8-iso-THC, and Δ(4)8-iso-THC were found. These findings highlight the urgency of improving regulations towards converting CBD to Δ8-THC for use as food ingredients.


Asunto(s)
Cannabidiol , Cannabinoides , Cannabis , Cannabinoides/análisis , Dronabinol/análisis , Cromatografía de Gases y Espectrometría de Masas , Cromatografía Líquida con Espectrometría de Masas
4.
Clín. investig. arterioscler. (Ed. impr.) ; 29(2): 60-66, mar.-abr. 2017. tab
Artículo en Inglés | IBECS (España) | ID: ibc-161016

RESUMEN

Aims: To test the hypothesis that the pattern of gene expression in circulating leukocytes may differ between vascular compartments, depending on the presence or absence of atherosclerosis, we evaluated the regional vascular differences in patterns of inflammatory cell activation. Methods: Patients (n = 8) with angiographically-established coronary artery disease (CAD+) and 8 without (CAD-) had blood samples taken from a peripheral vein as well as from left and right coronary arteries. Samples were pooled resulting in 4 CAD+ samples versus 4 CAD- samples and hybridised to a Whole Human Genome Microarray 4×44K. Results: CAD- patients had a similar gene expression profile across the different sites. CAD+ patients had statistically significant different gene expression patterns in venous vs. right and left coronary artery compartments. The expression pattern observed in the right coronary was where the most differences in gene expression were observed in CAD+ vs. CAD- patients. Overall, 1964 genes were differentially expressed between CAD+ and CAD−. Of these, 1052 were less expressed in CAD+ and 912 were more expressed in CAD+. Up to 12 of the 20 most differentially expressed genes appeared to reflect different phases of the atherosclerosis process: endothelial dysfunction, lipid accumulation, and smooth muscle cell proliferation. Conclusions: Gene expression of circulating leukocytes differentiates CAD+ from CAD- patients. Gene expression is significantly different between coronary arteries and the systemic circulation in CAD+ patients, but not in CAD- patients. Gene expression is significantly different between CAD+ and CAD- subjects, and appears to reflect the atherosclerosis process. These intra-individual differences may be an additional feature of established coronary artery disease


Objetivo: Para comprobar la hipótesis de que los patrones de expresión génica de leucocitos en circulación pueden ser diferentes entre los compartimentos vasculares dependiendo de la presencia o ausencia de arteriosclerosis, hemos evaluado en distintas regiones vasculares las diferencias entre los patrones de expresión y la activación de células inflamatorias. Métodos: Se extrajeron muestras de sangre de venas periféricas y de las arterias coronarias (derecha e izquierda) de pacientes con (n=8; CAD+) y sin (n=8; CAD−) enfermedad arterial coronaria establecida angiográficamente. Las muestras fueron hibridadas en dos pooles de 4 muestras (CAD+ vs CAD−) mediante el kit Whole Human Genome Microarray 4×44K. Resultados: Los pacientes CAD- tenían un perfil de expresión génica similar entre los distintos compartimentos vasculares. Los pacientes CAD+ tenían patrones de expresión génica significativamente diferentes entre los compartimentos venosos y las arterias coronarias derecha e izquierda. El patrón de expresión observado en la arteria coronaria derecha fue el que presentó más diferencias entre los pacientes CAD+ vs. CAD-. En conjunto, 1.964 genes estaban expresados diferencialmente entre CAD+ y CAD-. De estos, 1.052 estaban menos expresados en CAD+ i 912 estaban más expresados en CAD+. Hasta 12 de los 20 genes más diferencialmente expresados estaban relacionados con las diferentes fases del proceso arteriosclerótico: disfunción endotelial, acumulación lipídica y proliferación de células musculares lisas. Conclusiones: La expresión génica de leucocitos circulantes diferencia pacientes CAD+ de CAD-. La expresión genética es significativamente diferente entre arterias coronarias y circulación sistémica en pacientes CAD+, pero no en pacientes CAD-. Estas diferencias intraindividuales podrían ser una característica adicional en el diagnóstico de la enfermedad arterial coronaria


Asunto(s)
Humanos , Enfermedad de la Arteria Coronaria/fisiopatología , Leucocitos , ARN/análisis , Aterosclerosis/fisiopatología , Expresión Génica , Endotelio Vascular/fisiopatología , Lipidosis/fisiopatología , Miocitos del Músculo Liso
5.
Clín. investig. arterioscler. (Ed. impr.) ; 26(4): 184-192, jul.-ago. 2014. ilus
Artículo en Inglés | IBECS (España) | ID: ibc-125399

RESUMEN

Postprandial lipemia has been associated with cardiovascular disease. The current pathophysiological concept is that postprandial remnant lipoproteins migrate into the subendothelial space and that remnants activate circulating leukocytes and endothelial cells. Activated monocytes adhere to endothelial adhesion molecules, facilitating subendothelial migration of monocytes. These cells differentiate into macrophages, with the risk of foam cell formation, due to uptake of remnants and modified lipoproteins. Evidence is emerging that specific interventions may reduce the atherogenic postprandial inflammation. Fruits rich in polyphenols, virgin olive oil, carotenoids and exercise have recently been found to reduce postprandial inflammation. Pharmaceutical interventions with fibrates or statins not only improve the overall lipid profile, but reduce postprandial inflammation as well. This review will deal with the current concept of postprandial inflammation in relation to the development of atherosclerosis and potential interventions to reduce postprandial inflammation


La lipidemia posprandial está relacionada con la enfermedad cardiovascular. El concepto patofisiológico actual es que las partículas remanentes traspasan el endotelio, activan los leucocitos y las células endoteliales. Los monocitos activados se adhieren a la paredendotelial por mediación de moléculas de adhesión, facilitando así la migración de los monocitos al espacio subendotelial. Estas células se transforman en macrófagos, convirtiéndose definitivamente en células espumosas después de haber internalizado las partículas remanentes y otras lipoproteínas modificadas. Recientes estudios sugieren que existen intervenciones efectivas para modular la inflamación posprandial, y de esta forma rebajar el riesgo cardiovascular. Frutas ricas en polifenoles, aceite de oliva virgen, el caroteno y el ejercicio son ejemplos que han demostrado una reducción de la inflamación posprandial. El tratamiento con estatinas y fibratos no solo mejora el perfil lipídico, sino que también rebaja la lipidemia posprandial. Esta revisión describe los recientes conceptos de la inflamación posprandial relacionada con la generación de ateroesclerosis y también trata las intervenciones que pueden influir positivamente en la inflamación posprandial


Asunto(s)
Humanos , Hiperlipidemias/fisiopatología , Arteriosclerosis/fisiopatología , Apolipoproteína B-48/análisis , Periodo Posprandial , Enfermedades Cardiovasculares/epidemiología , Remanentes de Quilomicrones/análisis , Triglicéridos/análisis , Lipoproteínas VLDL/análisis , Lipólisis/fisiología
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