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1.
Anal Methods ; 16(12): 1793-1803, 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38436418

RESUMO

We developed a facile electroanalytical system for the rapid and sensitive detection of pyrimethanil through the modification of carbon paste electrode surface using the as-fabricated europium doped feather-type CuO nanoflowers (FT-Eu3+-CuO NF sensor). The peak current of pyrimethanil oxidation was elevated by the sensor due to the integration of appreciable electrochemical features of the modifier, which indicates the high ability of the modified electrode to enhance the sensitivity of pyrimethanil detection. The pyrimethanil sensor under the optimized setting had a broad linear dynamic range (0.001-800.0 µM) and a narrow limit of detection (0.18 nM). The practical applicability of the as-fabricated electrode was verified by sensing pyrimethanil in real samples; it also exhibited commendable specificity, stability and reproducibility.


Assuntos
Fungicidas Industriais , Pirimidinas , Água , Frutas , Reprodutibilidade dos Testes
2.
Nanoscale Adv ; 5(22): 6177-6193, 2023 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-37941952

RESUMO

We designed and prepared a novel N-heterocycle-based nanocatalyst by a post synthetic method, namely the [Fe3O4@DAA-BTrzPhen-Cu(ii)] composite. In this method, bistriazolyl-phenanthroline groups were stepwise synthesized on an Fe3O4 substrate and used as a tetradentate nitrogenous ligand for coordinating to copper ions. The obtained nanocomposite was well characterized using FT-IR, PXRD, TGA, EDAX, ICP-OES, EDX-mapping, SEM, TEM, VSM and BET analyses, which confirm the formation of a thermostable crystalline spherical particle morphology with the particle size in the range of 17 nm to 25 nm and a magnetization value of 42 emu g-1. Also, the catalytic activity of [Fe3O4@DAA-BTrzPhen-Cu(ii)] as a novel and magnetically separable heterogeneous nanocatalyst was evaluated in preparing various tetrasubstituted imidazole derivatives from one-pot four-component condensation of anilines, aldehydes, 1,2-diketones and ammonium acetate, and favorable products were produced with excellent yields. The stability, low Cu leaching, and heterogenous nature of the nanocatalyst were confirmed by hot-filtration and leaching tests. The copper based nanocatalyst could be easily recovered by magnetic field separation and recycled at least 8 times in a row without noticeable loss in its catalytic activity.

3.
J Mol Graph Model ; 125: 108605, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37660616

RESUMO

In this project, the possibility of drug delivery application of three anti-Multiple sclerosis (MS) agents (containing diroximel fumarate (DXF), dimethyl fumarate (DMF), and mono methyl fumarate (MMF)) by using some heteroatom decorated graphitic carbonitride (g-C3N4) (as nano-sized carriers) have been systematically investigated. The results of the study have indicated that As-g-C3N4 QD is not a suitable candidate for drug delivery (at least in the cases of DMF, and DXF drugs); while, it would be an accurate semiconductor sensor for selective detection of each mentioned agents. Also, the use of the P-doped as well as pristine g-C3N4 QD could lead to weak electronic signals with relatively same values (in electronvolts). It means that P-g-C3N4, and g-C3N4 QDs are not good sensors for detection of each of the three considered drugs. However, those two sorbents would be suitable carriers for delivering of all three mentioned pharmaceuticals.


Assuntos
Grafite , Esclerose Múltipla , Humanos , Esclerose , Probabilidade , Fumarato de Dimetilo , Sistemas de Liberação de Medicamentos , Esclerose Múltipla/tratamento farmacológico
4.
Comput Biol Med ; 158: 106832, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37037148

RESUMO

BACKGROUND AND OBJECTIVE: The molecular dynamics (MD) simulation is a powerful tool for researching how cancer patients are treated. The efficiency of many factors may be predicted using this approach in great detail and with atomic accuracy. METHODS: The MD simulation method was used to investigate the impact of porosity and the number of cancer cells on the atomic behavior of cancer cells during the hematogenous spread. In order to examine the stability of simulated structures, temperature and potential energy (PE) values are used. To evaluate how cell structure has changed, physical parameters such as gyration radius, interaction force, and interaction energy are also used. RESULTS: The findings demonstrate that the samples' gyration radius, interaction energy, and interaction force rose from 41.33 Å, -551.38 kcal/mol, and -207.10 kcal/mol Å to 49.49, -535.94 kcal/mol, and -190.05 kcal/mol Å, respectively, when the porosity grew from 0% to 5%. Also, the interaction energy and force in the samples fell from -551.38 kcal/mol and -207.10 kcal/mol to -588.03 kcal/mol and -237.81 kcal/mol Å, and the amount of gyration radius reduced from 41.33 to 37.14 Å as the number of cancer cells rose from 1 to 5 molecules. The strength and stability of the simulated samples will improve when the radius of gyration is decreased. CONCLUSIONS: Therefore, high accumulation of cancer cells will make them resistant to atomic collapse. It is expected that the results of this simulation should be used to optimize cancer treatment processes further.


Assuntos
Simulação de Dinâmica Molecular , Neoplasias , Humanos , Porosidade , Simulação de Acoplamento Molecular
5.
Ecotoxicol Environ Saf ; 256: 114857, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37030051

RESUMO

In this study, the mechanism of diazinon adsorption on single-walled carbon nanotubes (SWNTs), as well as multi-walled carbon nanotubes (MWNTs), was investigated using molecular modelling. Determination of the lowest energy sites of different types of carbon nanotubes (CNTs) was demonstrated. The adsorption site locator module was used for this purpose. It was found that the 5-walled CNTs are the best MWNTs for diazinon elimination from water due to their higher interactions with diazinon. In addition, the adsorption mechanism in SWNT and MWNTs was determined to be wholly adsorption on the lateral surface. It is because the geometrical size of diazinon molecules is larger than the inner diameter of SWNT and MWNTs. Furthermore, the contribution of diazinon adsorption on the 5-wall MWNTs was the highest, for the lowest diazinon concentration in the mixture.


Assuntos
Nanotubos de Carbono , Praguicidas , Água , Diazinon
6.
Biofactors ; 49(4): 718-735, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36876465

RESUMO

Drug resistance is a hot topic issue in cancer research and therapy. Although cancer therapy including radiotherapy and anti-cancer drugs can kill malignant cells within the tumor, cancer cells can develop a wide range of mechanisms to resist the toxic effects of anti-cancer agents. Cancer cells may provide some mechanisms to resist oxidative stress and escape from apoptosis and attack by the immune system. Furthermore, cancer cells may resist senescence, pyroptosis, ferroptosis, necroptosis, and autophagic cell death by modulating several critical genes. The development of these mechanisms leads to resistance to anti-cancer drugs and also radiotherapy. Resistance to therapy can increase mortality and reduce survival following cancer therapy. Thus, overcoming mechanisms of resistance to cell death in malignant cells can facilitate tumor elimination and increase the efficiency of anti-cancer therapy. Natural-derived molecules are intriguing agents that may be suggested to be used as an adjuvant in combination with other anticancer drugs or radiotherapy to sensitize cancer cells to therapy with at least side effects. This paper aims to review the potential of triptolide for inducing various types of cell death in cancer cells. We review the induction or resistance to different cell death mechanisms such as apoptosis, autophagic cell death, senescence, pyroptosis, ferroptosis, and necrosis following the administration of triptolide. We also review the safety and future perspectives for triptolide and its derivatives in experimental and human studies. The anticancer potential of triptolide and its derivatives may make them effective adjuvants for enhancing tumor suppression in combination with anticancer therapy.


Assuntos
Antineoplásicos , Diterpenos , Neoplasias , Humanos , Neoplasias/tratamento farmacológico , Morte Celular , Apoptose , Diterpenos/farmacologia , Diterpenos/uso terapêutico , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico
7.
Nanomaterials (Basel) ; 12(24)2022 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-36558322

RESUMO

New nanocomposites containing zirconium were synthesized using microwave irradiation. Their structure was confirmed by vibrating sample magnetometer (VSM) curves, X-ray diffraction (XRD) patterns, scanning electron microscope (SEM) and transmission electron microscopy (TEM) images, Fourier transform infrared spectroscopy (FT-IR), and Brunauer-Emmett-Teller (BET) N2 adsorption/desorption isotherms. After the structure confirmation of the zirconium magnetic nanocomposite, the catalytic properties in the synthesis of pyrazole derivatives were investigated. Next, the biological activities of the zirconium magnetic nanocomposite, such as the antibacterial and antifungal activities, were investigated. The research results showed that the zirconium magnetic nanocomposite has high catalytic properties and can be used as a magnetic nanocatalyst for synthesizing heterocyclic compounds such as pyrazole derivatives in addition to having high biological properties. The unique properties of the nanoparticles can be attributed to their synthesis method and microwave radiation.

8.
Heliyon ; 8(11): e11373, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36387551

RESUMO

In this paper, the thermal conductivity (knf) of cerium oxide/ethylene glycol nanofluid is extracted for different temperatures (T = 25, 30, 35, 40, 45, and 50 °C) and the volume fraction of nanoparticles ( φ = 0, 0.25, 0.5, 0.75, 1, 1.5, 2 and 2.5%) and then knf is predicted by two methods including Artificial Neural Network (ANN) and fitting method. For both methods, the results have been presented and compared. The experiments showed that with increasing φ and temperature, the thermal conductivity ratio (TCR) of nanofluid increases. It was also observed that when the experiments are performed at high temperatures, the rate of increase in knf is much higher than the change in the same amount of φ change at low temperatures. An ANN with 7 neurons has a correlation coefficient very close to 1 and this proves that the outputs are compatible with experimental results. Also, it can be seen that the ANN could predict the thermal behavior of cerium oxide/ethylene glycol nanofluid more accurately.

9.
J Photochem Photobiol B ; 236: 112571, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36215792

RESUMO

The novel Ag0/Cu2MoO4 nanoparticles was simply synthesized via chemical method. Ag/Cu2MoO4 nanoparticles was characterized by FESEM image, XRD curve, UV-vis spectroscopy, BET analysis, and XPS spectrum. XRD pattern depicts that the cubic crystalline phase of particles. The band gap of Ag/Cu2MoO4 nanoparticles was achieved to 2.04 eV, which that depicted the best activity under visible light irradiation. Ag/Cu2MoO4 nanoparticles exhibits 99.74% degradation under light and persulfate ion which was higher response than Cu2MoO4 nanoparticles (83.56%) under this condition. The scavenging test indicates the important reactive species in removal process were •OH, and •SO4-. The Ag/Cu2MoO4 nanoparticles was indicated highly photo-stability for the MG degradation after 5th cycle. Ag/Cu2MoO4 exhibits substantial antibacterial properties against P. aeruginosa and S. pneumoniae. Moreover, Ag/Cu2MoO4 nanoparticles was experimented to peroxidase-like performance for the colorimetric detection of glucose with the Limit of Detection about 52.23 nM.


Assuntos
Glucose , Nanopartículas , Catálise , Antibacterianos/farmacologia , Antibacterianos/química , Luz
10.
Front Chem ; 10: 1014731, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36300031

RESUMO

Using the microwave-assisted method, novel Fe3O4/Zn-metal organic framework magnetic nanostructures were synthesized. The crystallinity, thermal stability, adsorption/desorption isotherms, morphology/size distribution, and magnetic hysteresis of synthesized Fe3O4/Zn-metal organic framework magnetic nanostructures were characterized by XRD patterns, TGA curve, BET adsorption/desorption technique, SEM image, and VSM curve, respectively. After confirming the Fe3O4/Zn-metal organic framework magnetic nanostructures, its antimicrobial properties against Gram-positive bacterial, Gram-negative bacterial, and fungal strains based on minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), and minimum fungicidal concentration (MFC) values were studied. The MIC values in antimicrobial activity for Gram-positive and Gram-negative bacterial strains, between 16-128 µg/ml, and for fungal strain, 128 µg/ml were observed. The results showed that the high specific surface area of Fe3O4/Zn-metal organic framework magnetic nanostructures caused the antimicrobial power of nanoparticles to be high, and the observed antimicrobial effects were higher than some known commercial antimicrobial drugs. Another advantage of the specific surface area of Fe3O4/Zn-metal organic framework magnetic nanostructures was its high catalytic properties in the three-component reaction of isatin, malononitrile, and dimedone. New spiro [indoline-pyranopyrimidines] derivatives were synthesized with high efficiency. The catalytic activity results of Fe3O4/Zn-metal organic framework magnetic nanostructures showed that, in addition to recyclability, derivatives could be synthesized in less time than previously reported methods. The results of investigating the catalytic activity of Fe3O4/Zn-metal organic framework magnetic nanostructures showed that the spiro [indoline-pyranopyrimidines] derivatives were synthesized in the time range of 10-20 min with an efficiency of over 85%. As a final result, it can be concluded that the microwave synthesis method improves the unique properties of magnetic nanostructures, especially its specific surface area, and has increased its efficiency.

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