Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 5 de 5
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Dalton Trans ; 52(40): 14649-14662, 2023 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-37791584

RESUMO

This study investigates the impacts of structure and composition on the optical and electronic properties of a series of pyridinium-based bismuth iodide complexes. Organic substrates with various functional groups, such as 4-aminopyridine (4-Ampy), 4-methylpyridine (4-Mepy), 4-dimethylaminopyridine (4-Dmapy), and 4-pyridinecarbonitrile (4-CNpy) with different electron-donating and electron-withdrawing groups at the para position of the pyridine ring were employed. Crystallographic analysis reveals various bismuth iodide structures, including 1D chains and discrete 0D motifs. The optical band gap of these materials, identified via diffuse reflectance spectroscopy (DRS) and verified with density functional theory (DFT) calculations, is influenced by the crystal packing and stabilising interactions. Through a comprehensive analysis, including Hirshfeld surface (HS) and void assessment, the study underscores the influence of noncovalent intermolecular interactions on crystal packing. Spectroscopic evaluations provide insights into electronic interactions, elucidating the role of electron donor and acceptor substituents within the lattice. Thermogravimetric differential thermal analysis (TG-DTA) indicates structural stability up to 250 °C. Linear sweep voltammetry (LSV) reveals significant conductivity in the range of 10-20 mS per pixel at 298.15 K. X-ray absorption spectroscopy (XAS) at the Bi L3 edge indicates a similar oxidation state and electronic environment across all samples, underscoring the role of bismuth centres surrounded by iodides.

2.
Bioimpacts ; 11(4): 237-244, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34631485

RESUMO

Introduction: Further development of magnetic-based detection techniques could be of significant use in increasing the sensitivity of detection and quantification of hepatitis B virus (HBV) infection. The present work addresses the fabrication and characterization of a new bio-nano composite based on the immobilization of goat anti-HBsAg antibody on modified core-shell magnetic nanoparticles (NPs) by (3-aminopropyl) triethoxysilane (APTES), named Fe3O4@SiO2/NH2, and magnetic NPs modified by chitosan (Fe3O4@CS). Methods: At the first step, Fe3O4 was modified with the silica and APTES (Fe3O4@SiO2/NH2) and chitosan (Fe3O4@CS) separately. The goat anti-HBsAg antibody was activated by two different protocols: Sodium periodate and EDC-NHS. Then the resulted composites were conjugated with activated goat anti-HBsAg IgG. An external magnet collected Bio-super magnetic NPs (BSMNPs) and the remained solution was analyzed by the Bradford method to check the amount of attached antibody to the surface of BSMNPs. Results: The findings indicated that activation of antibodies by sodium periodate method 15-17 µg antibody immobilized on 1 mg of super magnetic nanoparticles (SMNPs). However, in the EDC-NHS method, 8-10 µg of antibody was conjugated with 1 mg of SMNPs. The resulting bio-magnetic NPs were applied for interaction with the HBsAg target using enzyme-linked immunosorbent assay (ELISA). About 1 µg antigen attached to 1 mg SMNPs, which demonstrated that the fabricated materials are applicable in the detection scope of HBsAg. Conclusion: In the present study, we developed new antibody-conjugated magnetic NPs for the detection of HBsAg using an efficient conjugation strategy. The results demonstrated that the binding capacity of Fe3O4@SiO2/NH2 was comparable with commercially available products. Our designed method for conjugating anti-HBsAg antibody to a magnetic nanoparticle opens the way to produce a high capacity of magnetic NPs.

3.
Nanomaterials (Basel) ; 11(9)2021 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-34578583

RESUMO

Doping and its consequences on the electronic features, optoelectronic features, and magnetism of graphynes (GYs) are reviewed in this work. First, synthetic strategies that consider numerous chemically and dimensionally different structures are discussed. Simultaneous or subsequent doping with heteroatoms, controlling dimensions, applying strain, and applying external electric fields can serve as effective ways to modulate the band structure of these new sp2/sp allotropes of carbon. The fundamental band gap is crucially dependent on morphology, with low dimensional GYs displaying a broader band gap than their bulk counterparts. Accurately chosen precursors and synthesis conditions ensure complete control of the morphological, electronic, and physicochemical properties of resulting GY sheets as well as the distribution of dopants deposited on GY surfaces. The uniform and quantitative inclusion of non-metallic (B, Cl, N, O, or P) and metallic (Fe, Co, or Ni) elements into graphyne derivatives were theoretically and experimentally studied, which improved their electronic and magnetic properties as row systems or in heterojunction. The effect of heteroatoms associated with metallic impurities on the magnetic properties of GYs was investigated. Finally, the flexibility of doped GYs' electronic and magnetic features recommends them for new electronic and optoelectronic applications.

4.
RSC Adv ; 10(66): 40019-40029, 2020 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-35520861

RESUMO

The discovery of properties and applications of unknown materials is one of the hottest research areas in materials science. In this work, we navigate a route towards these goals by the development of a new type of graphyne nanostructure. It is synthesised by a Sonogashira cross-coupling reaction of 1,3,5-triethynylbenzene with cyanuric chloride resulting in an extended carbon-based material called TCC. Also, we modify the obtained TCC via fluorination using XeF2 at various concentrations to investigate the effect of fluorination on the triple bonds and the conjugated structure of graphyne. In this study, we put special emphasis on the determination of the impact of the fluorine content and the type of CF functionalities on the morphology, chemical and electronic structure, biocompatibility, electrical conductivity and possible applicability as anode materials for Li-ion batteries. The obtained results indicate that the character of C-F bonds influences the final properties of fluorinated materials. The polar C-F bonds are preferable for cell proliferation while CF2 groups are most suitable for battery devices, however, the appearance of PTFE-like units may have a negative impact on battery specific capacitance as well as on cell viability.

5.
Pharmacognosy Res ; 7(4): 322-8, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-26692745

RESUMO

BACKGROUND: Ferulago macrocarpa is a plant used as flavoring agent and protectant in the food industry and as a folk medicinal plant in Iran with no available information on its chemical identity. Ferulago spp. showed to contain biologically terpenoids and coumarins. OBJECTIVE: The objective was to isolate and characterize terpenoids and coumarins from the acetone extract of F. macrocarpa fruits and to evaluate their antiproliferative effects on several cell lines. MATERIALS AND METHODS: A series of normal and reverse phase gravity and high-performance liquid chromatography analyses were used to purify constituents. Compounds 1-5 and 7 were evaluated for their cytotoxic effects on MCF-7, HT-29 and H-1299 cell lines. RESULTS: Six compounds including bornyl acetate (1), 1,10-di-epi-cubenol (2), stigmasterol (3) and three coumarins grandivittin (4), prantschimgin (5) and 4"-hydroxygrandivittin (7) along with mixtures of feruloyl derivatives (6a-6c) have been purified. Their structures were established by spectroscopic methods including nuclear magnetic resonance and MS analyses. Compound 2 showed moderate cytotoxicity effect with IC50 values of 5.0 and 6.7 mM on MCF-7 and HT-29, respectively. CONCLUSION: 1,10-di-epi-Cubenol could be considered as a potential proliferation inhibitor of MCF-7 and HT-29 cell lines.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...