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1.
Small ; : e2403736, 2024 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-38990899

RESUMEN

Transition metal selenides (TMSs) are receiving considerable interest as improved anode materials for sodium-ion batteries (SIBs) and lithium-ion batteries (LIBs) due to their considerable theoretical capacity and excellent redox reversibility. Herein, ZIF-12 (zeolitic imidazolate framework) structure is used for the synthesis of Cu2Se/Co3Se4@NPC anode material by pyrolysis of ZIF-12/Se mixture. When Cu2Se/Co3Se4@NPC composite is utilized as an anode electrode material in LIB and SIB half cells, the material demonstrates excellent electrochemical performance and remarkable cycle stability with retaining high capacities. In LIB and SIB half cells, the Cu2Se/Co3Se4@NPC anode material shows the ultralong lifespan at 2000 mAg-1, retaining a capacity of 543 mAhg-1 after 750 cycles, and retaining a capacity of 251 mAhg-1 after 200 cycles at 100 mAg-1, respectively. The porous structure of the Cu2Se/Co3Se4@NPC anode material can not only effectively tolerate the volume expansion of the electrode during discharging and charging, but also facilitate the penetration of electrolyte and efficiently prevents the clustering of active particles. In situ X-ray difraction (XRD) analysis results reveal the high potential of Cu2Se/Co3Se4@NPC composite in building efficient LIBs and SIBs due to reversible conversion reactions of Cu2Se/Co3Se4@NPC for lithium-ion and sodium-ion storage.

2.
Mikrochim Acta ; 191(4): 221, 2024 03 27.
Artículo en Inglés | MEDLINE | ID: mdl-38536529

RESUMEN

The successful fabrication is reported of highly crystalline Co nanoparticles interconnected with zeolitic imidazolate framework (ZIF-12) -based amorphous porous carbon using the molten-salt-assisted approach utilizing NaCl. Single crystal diffractometers (XRD), and X-ray photoelectron spectroscopy (XPS) analyses confirm the codoped amorphous carbon structure. Crystallite size was calculated by Scherrer (34 nm) and Williamson-Hall models (42 nm). The magnetic properties of NPCS (N-doped porous carbon sheet) were studied using a vibrating sample magnetometer (VSM). The NPCS has a magnetic saturation (Ms) value of 1.85 emu/g. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) analyses show that Co/Co3O4 nanoparticles are homogeneously distributed in the carbon matrix. While a low melting point eutectic salt acts as an ionic liquid solvent, ZIF-12, at high temperature, leading cobalt nanoparticles with a trace amount of Co3O4 interconnected by conductive amorphous carbon. In addition, the surface area (89.04 m2/g) and pore architectures of amorphous carbon embedded with Co nanoparticles are created using the molten salt approach. Thanks to this inexpensive and effective method, the optimal composite porous carbon structures were obtained with the strategy using NaCl salt and showed distinct electrochemical performance on electrochemical methodology revealing the analytical profile of Erdatifinib (ERD) as a sensor modifier. The linear response spanned from 0.01 to 7.38 µM, featuring a limit of detection (LOD) of 3.36 nM and a limit of quantification (LOQ) of 11.2 nM. The developed sensor was examined in terms of selectivity, repeatability, and reproducibility. The fabricated electrode was utilized for the quantification of Erdafitinib in urine samples and pharmaceutical dosage forms. This research provides a fresh outlook on the advancements in electrochemical sensor technology concerning the development and detection of anticancer drugs within the realms of medicine and pharmacology.


Asunto(s)
Antineoplásicos , Cobalto , Óxidos , Pirazoles , Quinoxalinas , Cloruro de Sodio , Reproducibilidad de los Resultados , Carbono/química
3.
Small ; : e2307225, 2023 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-38054760

RESUMEN

Ni/Mn-based oxide cathode materials have drawn great attention due to their high discharge voltage and large capacity, but structural instability at high potential causes rapid capacity decay. How to moderate the capacity loss while maintaining the advantages of high discharge voltage remains challenging. Herein, the replacement of Mn ions by Ga ions is proposed in the P2-Na2/3 Ni0.2 Mn0.8 O2 cathode for improving their cycling performances without sacrificing the high discharge voltage. With the introduction of Ga ions, the relative movement between the transition metal ions is restricted and more Na ions are retained in the lattice at high voltage, leading to an enhanced redox activity of Ni ions, validated by ex situ synchrotron X-ray absorption spectrum and X-ray photoelectron spectroscopy. Additionally, the P2-O2 phase transition is replaced by a P2-OP4 phase transition with a smaller volume change, reducing the lattice strain in the c-axis direction, as detected by operando/ex situ X-ray diffraction. Consequently, the Na2/3 Ni0.21 Mn0.74 Ga0.05 O2 electrode exhibits a high discharge voltage close to that of the undoped materials, while increasing voltage retention from 79% to 93% after 50 cycles. This work offers a new avenue for designing high-energy density Ni/Mn-based oxide cathodes for sodium-ion batteries.

4.
J Enzyme Inhib Med Chem ; 35(1): 489-497, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31914827

RESUMEN

A series of amino acid-sulphonamide conjugates was prepared through benzotriazole mediated coupling reactions and characterised by 1H-NMR, 13C-NMR, MS, and FTIR spectroscopic techniques as well as elemental analysis. The carbonic anhydrase (CA, EC 4.2.1.1) inhibitory activity of the new compounds was determined against four human (h) isoforms, hCA I, hCA II, hCA VA, and hCA XII. Most of the synthesised compounds showed effective in vitro CA inhibitory properties. The new amino acid-sulphonamide conjugates showed potent inhibitory activity against hCA II, some of them at subnanomolar levels, exhibiting more effective inhibitory activity compared to the standard drug acetazolamide. Some of these sulphonamides were also found to be effective inhibitors of hCA I, hCA VA, and hCA XII, with activity from the low to high nanomolar range.


Asunto(s)
Aminoácidos/farmacología , Inhibidores de Anhidrasa Carbónica/farmacología , Anhidrasas Carbónicas/metabolismo , Sulfonamidas/farmacología , Aminoácidos/síntesis química , Aminoácidos/química , Inhibidores de Anhidrasa Carbónica/síntesis química , Inhibidores de Anhidrasa Carbónica/química , Humanos , Isoenzimas/antagonistas & inhibidores , Isoenzimas/metabolismo , Estructura Molecular , Sulfonamidas/síntesis química , Sulfonamidas/química
5.
Bioorg Chem ; 83: 414-423, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30419497

RESUMEN

Thirty novel sulfonamide derivatives incorporating dipeptide were synthesized by facile acylation through benzotriazole mediated reactions and their structures were identified by 1H NMR, 13C NMR, MS and FT-IR spectroscopic techniques and elemental analysis. The carbonic anhydrase (CA, EC 4.2.1.1) inhibitory activity of the new compounds was assessed against four human (h) isoforms, hCA I, hCA II, hCA IV and hCA XII. Most of the synthesized compounds showed excellent in vitro carbonic anhydrase inhibitory properties comparable to those of the clinically used drug acetazolamide (AAZ). The new unprotected dipeptide-sulfonamide conjugates showed very effective inhibitory activity, in the low nanomolar range against II and XII, being less effective as hCA I and IV inhibitors. Four of the thirty compounds also showed strong inhibitory activity against hCA XII compared to AAZ.


Asunto(s)
Inhibidores de Anhidrasa Carbónica/química , Dipéptidos/química , Sulfonamidas/química , Inhibidores de Anhidrasa Carbónica/síntesis química , Anhidrasas Carbónicas/química , Dipéptidos/síntesis química , Humanos , Isoenzimas/antagonistas & inhibidores , Estructura Molecular , Relación Estructura-Actividad , Sulfonamidas/síntesis química
6.
Bioorg Chem ; 81: 311-318, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30176570

RESUMEN

Twenty-four novel sulfonamide derivatives incorporating dipeptide tails were synthesized by facile acylation reactions of homosulfanilamide through benzotriazole or dicyclohexyl carbodiimide (DCC) mediated coupling reactions. The carbonic anhydrase (CA, EC 4.2.1.1) inhibitory activity of the new compounds was assessed against four human (h) isoforms, hCA I, hCA II, hCA IX and hCA XII. Most of the synthesized compounds showed good in vitro carbonic anhydrase inhibitory properties, with inhibition constants in the low nanomolar range. Particularly, the new dipeptide-sulfonamide conjugates incorporating Ala, Phe and Met in the dipeptide sequence, showed the most effective inhibitory activity against to CA IX and XII.


Asunto(s)
Inhibidores de Anhidrasa Carbónica/química , Dipéptidos/química , Sulfonamidas/química , Antígenos de Neoplasias , Anhidrasa Carbónica I/antagonistas & inhibidores , Anhidrasa Carbónica II/antagonistas & inhibidores , Anhidrasa Carbónica IX/antagonistas & inhibidores , Inhibidores de Anhidrasa Carbónica/síntesis química , Dipéptidos/síntesis química , Humanos , Isoenzimas/antagonistas & inhibidores , Sulfonamidas/síntesis química
7.
J Enzyme Inhib Med Chem ; 31(6): 1221-5, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26598927

RESUMEN

N-protected amino acids were reacted with substituted benzothiazoles to give the corresponding N-protected amino acid-benzothiazole conjugates (60-89%). Their structures were confirmed by proton nuclear magnetic resonance ((1)H NMR), carbon-13 nuclear magnetic resonance ((13)C NMR), IR and elemental analysis. Their carbonic anhydrase (CA, EC 4.2.1.1) inhibitory activities were determined against two cytosolic human isoforms (hCA I and hCA II), one membrane-associated (hCA IV) and one transmembrane (hCA XII) enzyme by a stopped-flow CO2 hydrase assay method. The new compounds showed rather weak, micromolar inhibitory activity against most of these enzymes.


Asunto(s)
Benzotiazoles/síntesis química , Benzotiazoles/farmacología , Inhibidores de Anhidrasa Carbónica/síntesis química , Inhibidores de Anhidrasa Carbónica/farmacología , Espectroscopía de Resonancia Magnética con Carbono-13 , Espectroscopía de Protones por Resonancia Magnética
8.
Small Methods ; 7(11): e2300635, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37572008

RESUMEN

Sodium layered oxides feature in high capacity and diverse composition, however, are plagued by various issues including limited kinetics and interfacial instability with residual alkali. Conventional substitution/doping and heterogeneous coating are promising to tackle the problems of bulk and surface, respectively, but normally insufficient to address both. Herein, a post-substitution strategy is proposed to modify primary sodium-layered-oxide particles that can simultaneously deal with bulk and surficial issues. As a typical example, post Ti-substitution for O3-NaNi1/3 Fe1/3 Mn1/3 O2 is successfully performed by adjusting thermodynamic driving force, resulting in depth-controllable Ti infusion from surface to bulk, as proved by energy dispersive spectroscopy maps collected at the cross-section. Residual alkali species are efficiently diminished and benefited from the surface-to-bulk osmotic reaction, significantly improving Coulombic efficiency. Moreover, remarkable enhancements in reversible capacity (135 mAh g-1 at C/10), rate capability (74% retention at 5 C), and long-term cycling stability (80% retention after 300 cycles at 2 C) are achieved by manipulating gradient-like Ti distribution in a primary particle that brings with increased kinetics and strengthened interfacial stability, surpassing those given by rough heterotic coating and homogeneous Ti-substitution. Such post-substitution is expected to provide a universal strategy to modify primary layered-oxide particles for developing advanced cathode materials of SIBs.

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