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1.
Bioengineering (Basel) ; 10(3)2023 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-36978670

RESUMO

Hybrid materials are classified as one of the most highly important topics that have been of great interest to many researchers in recent decades. There are many species that can fall under this category, one of the most important of which contain biopolymeric materials as a matrix and are additionally reinforced by different types of carbon sources. Such materials are characterized by many diverse properties in a variety industrial and applied fields but especially in the field of biomedical applications. The biopolymeric materials that fall under this label are divided into natural biopolymers, which include chitosan, cellulose, and gelatin, and industrial or synthetic polymers, which include polycaprolactone, polyurethane, and conducting polymers of variable chemical structures. Furthermore, there are many types of carbon nanomaterials that are used as enhancers in the chemical synthesis of these materials as reinforcement agents, which include carbon nanotubes, graphene, and fullerene. This research investigates natural biopolymers, which can be composed of carbon materials, and the educational and medical applications that have been developed for them in recent years. These applications include tissue engineering, scaffold bones, and drug delivery systems.

2.
Biomedicines ; 11(3)2023 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-36979948

RESUMO

The hybridization between polymers and carbon materials is one of the most recent and crucial study areas which abstracted more concern from scientists in the past few years. Polymers could be classified into two classes according to the source materials synthetic and natural. Synthetic polymeric materials have been applied over a floppy zone of industrial fields including the field of biomedicine. Carbon nanomaterials including (fullerene, carbon nanotubes, and graphene) classified as one of the most significant sources of hybrid materials. Nanocarbons are improving significantly mechanical properties of polymers in nanocomposites in addition to physical and chemical properties of the new materials. In all varieties of proposed bio-nanocomposites, a considerable improvement in the microbiological performance of the materials has been explored. Various polymeric materials and carbon-course nanofillers were present, along with antibacterial, antifungal, and anticancer products. This review spots the light on the types of synthetic polymers-based carbon materials and presented state-of-art examples on their application in the area of biomedicine.

3.
Mini Rev Med Chem ; 23(7): 821-851, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36545712

RESUMO

Viruses are still the most prevalent infectious pathogens on a worldwide scale, with many of them causing life-threatening illnesses in humans. Influenza viruses, because of their significant morbidity and mortality, continue to pose a major threat to human health. According to WHO statistics, seasonal influenza virus epidemics are predicted to cause over 2 million severe illness cases with high death rates yearly. The whole world has been suffering from the COVID-19 epidemic for two years and is still suffering so far, and the deaths from this virus have exceeded three million cases. Because the great majority of viral infections do not have a specific medication or vaccination, discovering novel medicines remains a vital task. This review covers reports in the patent literature from 1980 to the end of 2021 on the antiviral activities of pyrimidine moieties. The patent database, SciFinder, was used to locate patent applications. A large variety of pyrimidine molecules have been produced and tested for antiviral activity over the last decade. These molecules were reported to inhibit a wide range of viruses, including influenza virus, respiratory syncytial virus, rhinovirus, dengue virus, herpes virus, hepatitis B and C, and human immunodeficiency virus. The cytotoxicity of the developed pyrimidine derivatives was tested in almost all reported studies and the selectivity index was calculated to show the selectivity and safety of such molecules. From the remarkable activity of pyrimidine compounds as antivirals for several dangerous viruses, we expect that these derivatives will be used as potent drugs in the very near future.


Assuntos
COVID-19 , Influenza Humana , Humanos , Antivirais/farmacologia , Antivirais/uso terapêutico , Influenza Humana/tratamento farmacológico , Pirimidinas/farmacologia , Pirimidinas/uso terapêutico
4.
Bioorg Chem ; 128: 106043, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36058118

RESUMO

Novel tetracyclic pyrazolo[1,5-a]pyrimidine derivatives; namely benzo[3,4]cyclohepta[1,2-e]pyrazolo[1,5-a]pyrimidin-2-amines 6a-e and benzo[3,4]cyclohepta[1,2-e]pyrazolo[1,5-a]pyrimidin-2(6H)-ones 15a-d, were designed and synthesized as topoisomerase IIα inhibitors with potential anticancer activity. The structure and their mechanistic pathway were discussed and confirmed based on spectral data and DFT calculations. Compounds 6a, 6c, 15b, 15c and 15d exhibited potent Topo II inhibitory activity at one-digit IC50 values (2.35 - 7.18 µM). Among the tested compounds, aminopyrazolopyrimidine derivatives 6a (IC50 = 3.44 µM) and 6c (IC50 = 2.35 µM) were comparable/ equipotent to Doxorubicin (IC50 = 2.71 µM) against Topo II. The most active compounds in Topo II assay were further investigated in vitro for their cytotoxic potential. The oxo-pyrazolopyrimidine derivative 15c; was the most potent possessing one-digit IC50 values (HCT116 IC50 = 2.32 ± 0.13 µM, MCF7 IC50 = 1.137 ± 0.06 µM). Compound 15c was two times more potent than Doxorubicin against MCF7 breast cancer cells. 15c exhibited a safety profile much better than that of Doxorubicin against non-cancerous cells. Compound 15c was also found to be a good apoptotic inducer. Moreover, docking result revealed well-fitting and proper orientation of 15c into Topo II-DNA complex.


Assuntos
Antineoplásicos , Antineoplásicos/química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Proliferação de Células , Relação Dose-Resposta a Droga , Doxorrubicina/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Simulação de Acoplamento Molecular , Estrutura Molecular , Pirimidinas/química , Pirimidinas/farmacologia , Relação Estrutura-Atividade
6.
ACS Omega ; 6(34): 22180-22187, 2021 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-34497909

RESUMO

Nanocrystalline metal ferrites (MFe2O4, M = Co, Ni, Cu, Mg, and Zn) were successfully synthesized via autocombustion synthesis using egg white. X-ray diffraction (XRD) measurements revealed the crystallization of the entire ferrites either in the tetragonal structure, such as in the case of CuFe2O4, or cubic spinels such as in other studied ferrites. The Fourier transform infrared spectral study revealed the characteristic vibration bands of ferrites. Compared to other synthesis methods, the observed variation in the obtained structural parameters could be due to the different cation distribution of the prepared ferrites. In agreement with XRD measurements, the transmission electron microscopy images showed agglomerated particles with cubic morphology for all ferrites. On the other hand, CuFe2O4 showed tetragonal morphology. The magnetization values were found to vary with the type of the metal ion, and CoFe2O4 showed the highest one (42.8 emu/g). Generally, the lower magnetization values obtained than those reported in the literature for all studied ferrites could be attributed to the smaller particle sizes or the cation redistribution. The obtained coercivity values are observed to be higher than their related values in the literature, exhibiting the impact of the present synthesis route. Ac-conductivity as a function of temperature and frequency indicated semiconducting properties with the observed change in the conduction mechanism by increasing the temperature. The obtained low dielectric constant values could suggest using the entire ferrites in high-frequency applications such as microwave devices.

7.
Sci Rep ; 11(1): 5056, 2021 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-33658573

RESUMO

A unique network core-shell hybrid design-based cross-linked polyaniline (CPA), which was coated with CuO nanoparticles (NPs) and decorated with nitrogen-doped SWCNT/GO/cellulose N-SWCNTS-GO-CE, has been fabricated using the oxidative polymerization technique. This hybrid nanocomposite shows excellent photocatalytic degradation and an acceptable adsorption capability for Methyl Orange (MO) dye in aqueous solutions with a very slight effect for the N-SWCNTS-GO-CE CuO component. The prepared nanocomposites were used for the removal of a carcinogenic and noxious dye, Methyl Orange, from aqueous samples under various adsorption conditions. Approximately 100% degradation of 10 mg/L of Methylene orange dye was observed within 100 min at pH 6.0 using 50 mg/L CPA/N-SWCNTS-GO-CE/CuO nanocomposite under UV radiation. Additionally, significant factors were investigated on the degradation process including the contact time, MO initial concentration (Ci), solution pH, and dosage of the CuO nanocomposite. All investigated experiments were performed under UV radiation, which provided significant data for the MO degradation process. Furthermore, the recovery of the nanocomposite was studied based on the photocatalytic process efficiency. The obtained data provide the high opportunity of reusing CPA/N-SWCNTS-GO-CE/CuO nanocomposite for numerous photocatalytic processes. The CPA/N-SWCNTS-GO-CE/CuO nanocomposite was prepared via chemical oxidative copolymerization of polyaniline (PANI) with p-phenylenediamine (PPDA) and triphenylamine (TPA) in the presence of N-SWCNTS-GO-CE and CuO NPs. The morphology, structure and thermal properties of the CPA/N-SWCNTS-GO-CE/CuO nanocomposite were investigated using various techniques, including FTIR, XRD, RAMAN, SEM, MAP, EDX, TEM, TGA and DTG. Therefore, CPA/N-SWCNTS-GO-CE/CuO nanocomposite can be effectively used as a convenient and reusable adsorbent to remove hazardous dye from wastewater.

8.
PLoS One ; 15(6): e0234815, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32584837

RESUMO

Nanocomposites (NCs) of crosslinked polyaniline (CPA)-coated oxidized carbon nanomaterials (OXCNMs) were fabricated as a very sensitive and simple electrochemical sensor to be utilized in 2,4-dichlorophenol (2,4-DCPH) detection. CPA/OXCNMs NCs were prepared by chemical copolymerization of polyaniline with triphenylamine and p-phenylenediamine in the presence of OXCNMs. The CPA/GO-OXSWCNTNCs exhibited a higher affinity for the oxidation of chlorophenols compared to the glassy carbon electrode (GCE), CPA/GCE, and other NCs. Cyclic voltammetry was performed to investigate and assess the electrocatalytic oxidation of 2,4-DCPH on the modified GCE. The compound yielded a well-defined voltammetric response in a Britton-Robinson buffer (pH 5) at 0.54 V (vs. silver chloride electrode). Quantitative determination of 2,4-DCPH was performed by differential pulse voltammetry under optimal conditions in the concentration range of 0.05 to 1.2 nmol L-1, and a linear calibration graph was obtained. The detection limit (S/N = 3) was found to be 4.2 nmol L-1. In addition, the results demonstrated that the CPA/GO-OXSWCNTs/GCE sensor exhibited a strong anti-interference ability, reproducibility, and stability. The prepared CPA/GO-OXSWCNTs/GCE sensor was used to rapidly detect 2,4-DCPH with a high degree of sensitivity in fish farm water with proven levels of satisfactory recoveries.


Assuntos
Compostos de Anilina/química , Carbono/química , Clorofenóis/análise , Eletroquímica/instrumentação , Limite de Detecção , Nanocompostos/química , Clorofenóis/química , Eletrodos , Oxirredução , Fatores de Tempo
9.
RSC Adv ; 9(57): 33052-33070, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-35529122

RESUMO

In this study, we report a novel ternary conductive hybrid material with high stability, conductivity, and excellent electrochemical Ga3+ sensing ability. Ternary poly(pyrrole-co-o-toluidine)/CoFe2O4/reduced graphene oxide-oxidized single-wall carbon nanotube nanocomposites in the form of P(Py-co-OT)/CF/R(GO-OXSWCNTs) NCs have been synthesized through an in situ chemical polymerization method via a facile three-step approach. Single phase CoFe2O4 (CF) nanoparticles (NPs) were synthesized using an egg white method, while reduced graphene oxide-oxidized single-wall carbon nanotubes R(GO-OXSWCNTs) were prepared via co-reduction of graphene oxide along with oxidized SWCNTs flowed by coating CF and R(GO-OXSWCNTs) with a poly(pyrrole-co-o-toluidine) matrix P(Py-co-OT) copolymer. The results of X-ray diffraction spectroscopy (XRD), Fourier-transform infrared spectroscopy (FTIR) and Raman indicated that the P(Py-co-OT)/CF/R(GO-OXSWCNTs) NCs were effectively synthesized with strong interactions among the constituents. The thermal stability of P(Py-co-OT)/CF/R(GO-OXSWCNTs) NCs is considerably enhanced in the composite format. Scanning electron microscopy (SEM), transmission electron microscopy (TEM) and atomic force microscopy (AFM) demonstrated that CF and R(GO-OXSWCNTs) were well coated by P(Py-co-OT). The electrical conductivity study showed that P(Py-co-OT) and R(GO-OXSWCNTs) might significantly improve the conductivity and the electrochemical performance of the CF. A Ga3+ ion selective electrochemical sensor was fabricated by coating a glassy carbon electrode (GCE) with synthesized P(Py-co-OT)/CF/R(GO-OXSWCNTs) NCs by using 5% Nafion binder. The slope of the calibration curve was used to calculate the sensor's analytical parameters, such as sensitivity (13.0569 µA µM-1 cm-2), detection limit (96.27 ± 4.81 pM), quantification limit (43.523 pM), response time, reproducibility, large linear dynamic range, and linearity. The validation of the P(Py-co-OT)/CF/R(GO-OXSWCNTs) NCs/GCE sensor probe was investigated by a standard addition method (recovery) in the presence of various environmental samples and satisfying results were obtained.

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