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1.
ACS Omega ; 8(15): 13605-13625, 2023 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-37091434

RESUMO

A novel hydrazone ligand (o-H2BMP) N-(benzo[d]thiazol-2-yl)-3-oxo-3-(2-(1-(pyridin-2-yl)ethylidene)hydrazinyl)propanamide alongside its Cu(II), Cd(II), and VO(II) complexes were prepared and structurally characterized via various spectroscopic analyses (Fourier transform infrared spectroscopy, UV-visible spectroscopy, 1H/13C NMR spectroscopy, liquid chromatography coupled to mass spectrometry, and electron paramagnetic resonance spectroscopy) as well as by elemental analysis, thermal gravimetry analysis/differential thermal analysis, and magnetic moment measurements. Powder X-ray diffraction analysis was also performed for the free ligand and its metal complexes to determine the crystallographic structures and atomic spacing. It also provided information on unit cell dimensions and the average crystallite size. Furthermore, geometric optimization and computational studies were carried out by applying Gaussian (09) software based on density-functional theory coupled with the B3LYP functional and LANL2DZ/6-31+G(d,p) mixed basis set to evaluate some distinct features such as molecular electrostatic potential, E HOMO, and E LUMO. Moreover, electrochemical measurements were performed for Cu(II) in the absence/presence of the chelating agent to predict the effect of complexation interaction in the solution state study. As part of the biological examination, antioxidant and antimicrobial assays were conducted for each compound individually, in addition to cytotoxicity evaluations via MTT assays for all isolated complexes compared to the corresponding metal salts. The MOE (molecular operating environment) approach was also applied to model the interface between the isolated compounds and proteins that were expressed in breast cancer at the atomic level.

2.
ACS Omega ; 8(1): 1683-1692, 2023 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-36643554

RESUMO

Alkaline earth aluminates (AEAs) as photoluminescent agents and silicon dioxide-based electrospun glass nanofibers with an average diameter of 150-450 nm as a roughening agent were prepared and applied to reinforce an epoxy resin toward the development of long-persistent photoluminescent and photochromic smart materials, such as smart windows and anticounterfeiting barcodes. With the physical immobilization of lanthanide-doped aluminate nanoparticles (NPs), a light-induced luminescent transparent glass@epoxy film was developed. The glass@epoxy samples were able to alter their color to green beneath ultraviolet rays and greenish-yellow in the dark, as explored by CIE Lab and luminescence spectral analyses. The morphology of the lanthanide-doped aluminate nanoparticles (43-98 nm) was examined by transmission electron microscopy (TEM). The morphologies and chemical composition of the luminescent glass@epoxy substrates were determined by different analytical techniques. The mechanical properties of the developed photoluminescent glass@epoxy substrates were inspected to show improved scratch resistance as compared to the AEA-free substrate. The photoluminescence spectra were measured to indicate the detection of two emission bands at 494 and 525 nm when excited at 365 nm. The photoluminescent glass@epoxy hybrids with lower AEA contents have showed fast reversibility of photochromism. On the other hand, the glass@epoxy substrates with higher phosphor contents underwent persistent luminescence. Results showed that the luminescent colorless glass@epoxy hybrids have enhanced superhydrophobicity and ultraviolet blocking.

3.
RSC Adv ; 12(55): 35587-35597, 2022 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-36540397

RESUMO

This work reports the synthesis of an innovative multifunctional carbon nitride based adsorbent and its successful application for the removal of crystal violet (CV) and methylene blue (MB) from wastewater. The functionalized graphitic carbon nitride (f/g-CN) adsorbent was produced by the pyrolysis of melamine followed by thermal alkali treatment to introduce OH, NH x , and CN groups onto the graphitic carbon nitride (g-CN) surface. Experimental data obtained from batch tests revealed that the maximum adsorption capacities of g-CN and f/g-CN were found to be 28.9 and 239.0 mg g-1 for MB, and 163.0 and 532.0 mg g-1 for CV, respectively, at pH 8, 25 °C and after 90 min. This increase in adsorption capacity of f/g-CN can be explained by the presence of multiple functional groups in its structure. f/g-CN showed 100% removal for MB and CV with concentrations lower than 100 ppm and the equilibrium time required for the 100% removal of 500 ppb dye is 60 seconds. Additionally, the experimental data fitted well with the Langmuir isotherm model (R 2 = 0.992) and pseudo second order kinetic model (R 2 = 0.999) suggesting that the mechanism of adsorption is based on π-π stacking and electrostatic interactions between the NH x and OH groups of f/g-CN and dye molecules with monolayer formation. Moreover, a reusability test showed that the adsorption capacity remained at around 90% after 7 cycles. This work highlights the merits of the prepared adsorbent f/g-CN which is an eco-friendly, stable, efficient, and reusable adsorbent for removing cationic dyes from wastewater.

4.
Spectrochim Acta A Mol Biomol Spectrosc ; 132: 846-53, 2014 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-24996126

RESUMO

2-(2,4-Dichlorophenoxy)-N'-(2-hydroxybenzylidene)acetohydrazide (H2L) complexes were prepared by ball milling involving the reaction of ligand with Ni(II), Co(II), Cu(II) and VO(II) salts (mechanochemical syntheses). The compounds were elucidated by elemental analysis, spectroscopy (1H NMR, IR, UV-visible, MS spectra), and physical measurements (magnetic susceptibility and molar conductance). IR spectra suggested that the H2L behaved as a monodentate and/or bidentate ligand coordinating via azomethine nitrogen and/or deprotonated enolized carbonyl oxygen. The electronic spectra of the complexes and their magnetic moments provided information about geometries. The antimicrobial activities of the ligand and its complexes were studied against gram positive bacteria; Staphylococcus aureus, gram-negative bacteria; Escherichia coli and pathogenic fungi; Candida albicans by using minimum inhibition concentrations method (MIC). Also, the antioxidant (ABTS-derived free radical method) and cytotoxic (in vitro Ehrlich Ascites) activities of the isolated compounds were evaluated.


Assuntos
Complexos de Coordenação/síntese química , Química Verde/métodos , Hidrazonas/síntese química , Anti-Infecciosos/farmacologia , Antioxidantes/farmacologia , Bactérias/efeitos dos fármacos , Benzotiazóis/farmacologia , Morte Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Complexos de Coordenação/química , Complexos de Coordenação/farmacologia , Elétrons , Fungos/efeitos dos fármacos , Células Hep G2 , Humanos , Hidrazonas/química , Hidrazonas/farmacologia , Concentração Inibidora 50 , Ligantes , Fenômenos Magnéticos , Testes de Sensibilidade Microbiana , Espectroscopia de Prótons por Ressonância Magnética , Solventes , Espectrofotometria Infravermelho , Ácidos Sulfônicos/farmacologia
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