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1.
J Environ Manage ; 330: 117132, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36584468

RESUMO

Herein, the ternary CdS/BiVO4/g-C3N4 (CBG) hybrid semiconductor photocatalyst was prepared via a hydrothermal technique. The synthesized photocatalysts were thoroughly characterized using powder XRD, XPS, FTIR, SEM, TEM, and UV-DRS to investigate the microstructural, morphological attributes, and optical properties. The photocatalytic activity of the ternary CBG hybrid semiconductor was assessed through the photodegradation of Methylene Blue (MB) aqueous dye under visible light. The outcomes exhibited that the CBG hybrid semiconductor showed excellent photocatalytic activity (about 94.5% after 120 min) compared to the results obtained with the pristine materials or the other composite (CdS/BiVO4). The enhancement of photocatalytic activity can be due to the construction of heterojunctions among g-C3N4, CdS, and BiVO4, which improves charge transfer efficiency and hence favors the degradation of organic dyes. Moreover, the as-prepared photocatalyst showed excellent stability after five cycles, indicating good stability and reusability. Subsequently, a possible photocatalytic mechanism was proposed based on the experimental results. The current investigation provides a promising strategy to promote photocatalytic activity to eliminate waterborne contaminants.


Assuntos
Azul de Metileno , Nanocompostos , Luz , Corantes
2.
J Environ Manage ; 348: 119246, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37820430

RESUMO

Photocatalytic water decontamination has emerged as a highly promising technology for efficient and rapid water treatment, harnessing sustainable solar energy as its driving force. In this study, we prepared visible-light active Bi2S3/CoS2 composites for the degradation of naproxen (NPX) and the inactivation of Escherichia coli (E. coli). The homogeneous dispersion of CoS2 was stably integrated with Bi2S3, resulting in a significant enhancement of the specific surface area, efficient utilization of visible light, and effective separation of photogenerated charge carriers. Consequently, this synergistic photocatalytic system greatly facilitated the successful degradation of NPX and the inactivation of E. coli under visible-light irradiation. Compared to the pure Bi2S3 and CoS2 catalysts, the Bi2S3/CoS2 (1:2) composites displayed significantly enhanced photodegradation activity, achieving 96.46% (k = 0.2847 min-1) degradation of NPX within 90 min and maintaining good recyclability with no significant decline after six successive cycles. Additionally, the photocatalytic inactivation of E. coli results indicated that Bi2S3/CoS2 composites exhibited excellent performance, leading to the inactivation of 7 log10 cfu mL-1 of bacterial cells after 150 min of visible-light exposure. Scanning Electron Microscopy (SEM) and K+ ions leakage tests demonstrated that the destruction of the E. coli cell membrane structure resulted in cell death. The outcomes of this work suggest that Bi2S3/CoS2 composites hold significant potential for treating water contaminated with antibiotic and microbial pollutants.


Assuntos
Escherichia coli , Naproxeno , Naproxeno/farmacologia , Naproxeno/metabolismo , Luz , Antibacterianos/farmacologia , Antibacterianos/metabolismo , Microscopia Eletrônica de Varredura , Catálise
3.
Chemosphere ; 306: 135505, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35779680

RESUMO

A novel composite of multiwall carbon nanotube (MWCNT) supported V2O5 quantum dots decorated Bi2O3 hybrid was prepared by the simple wet-impregnation method, and the photocatalytic performance of the prepared samples was investigated against the photodegradation of ciprofloxacin (CIP). Herein, different samples of pristine, V2O5/Bi2O3 and MWCNT@V2O5/Bi2O3 hybrid photocatalyst were prepared and systematically characterized by various physicochemical techniques. The characterization results demonstrated that the introduction of MWCNT can change the energy band gap of V2O5/Bi2O3, and the band energies vary with a constituent of MWCNT@V2O5/Bi2O3 catalyst, in which MWCNT@V2O5/Bi2O3-5 (0.05 g@0.50 g:0.50 g) has the optimal band gap energy of 2.46 eV. The photocatalytic test demonstrates that the MWCNT@V2O5/Bi2O3-5 hybrid composites exhibited enhanced photocatalytic activity in CIP degradation compared to that pure and other photocatalyst and its degradation efficiency did not decrease significantly even after five cyclic experiments. The enhanced photocatalytic activity was due to the formation of heterojunction among MWCNT, V2O5 and Bi2O3, which distinctly improved the separation efficiency of the photogenerated charge carrier, thus increasing the degradation performance. This work gives a new approach to designing an efficient photocatalyst for contaminants degradation.


Assuntos
Nanotubos de Carbono , Pontos Quânticos , Bismuto/química , Ciprofloxacina , Luz
4.
Artif Cells Nanomed Biotechnol ; 48(1): 1206-1213, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33016139

RESUMO

Colon cancer is one of the major prevailing types of cancer worldwide. It has been the most important public health difficulty. Thus, we planned phytoconstituents arbitrated synthesis of gold nanoparticles (AuNPs) and examined their curative efficacy against the colon cancer (HCT-116) cells. In this current study, we formulated the AuNPs by using Albizia lebbeck (AL) aqueous leaf extract by the green method and synthesized AL-AuNPs were distinguished by UV-visible spectroscopy (UV-vis), energy dispersive X-ray diffraction (XRD), selected area (electron) diffraction (SAED) pattern, Fourier transform infrared spectroscopy (FTIR) and high-resolution transmission electron microscopy (HR-TEM). Synthesized AL-AuNPs confirmed by the UV absorption highest at 535 nm and the crystal structure of AL-AuNPs was additionally established by XRD and SAED pattern. HR-TEM images explained the size and morphology allocation of nanoparticles. FTIR analysis confirmed the presence of alkynes, aromatic compounds, and alkenes of biomolecules in AL-AuNPs. Furthermore, AL-AuNPs induced cytotoxicity at the IC50 concentration 48 µg/ml and also induced apoptosis by enhanced ROS production, decreased ΔΨm, apoptotic morphological changes by AO/EtBr and altering pro and anti-apoptotic protein expressions were analyzed in HCT-116 colon cancer cells. The findings of this investigation proved that the AL-AuNPs were revealed the potential anticancer activity against colon cancer (HCT-116) cells.


Assuntos
Albizzia/química , Anticarcinógenos/síntese química , Anticarcinógenos/farmacologia , Neoplasias do Colo/patologia , Ouro/química , Ouro/farmacologia , Nanopartículas Metálicas/química , Anticarcinógenos/química , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Técnicas de Química Sintética , Química Verde , Células HCT116 , Humanos , Extratos Vegetais/química
5.
Front Chem ; 7: 799, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31850301

RESUMO

Studies of the Ketalization reaction using trivalent alcohol glycerol in combination with acetone and their kinetics modeling are still limited. The focus of this current study is an investigation into HZSM-5 with various silica to alumina molar ratios (M = 35, 90, and 160) for the reaction between glycerol and acetone. In addition, the influence of reaction temperatures (25, 50, and 60°C) on the rate of the reaction have also been considered. Additionally, this investigation established the rate law for all HZMS-5 models (M = 35, 90, and 160) which showed "n" order equals half while the activation energy was found to be 164.34 kJ mol-1 with a constant reaction rate of k0 = 5.2678*1028 (Concentration1/2. min-1). Furthermore, MCM-41 pure mesoporous materials were separately treated using various methods. The first involved treatment using Dichlorodimethylsilane MCM 41(TD) and later treatment of a pure sample with sulfuric acid MCM-41. The sulfated MCM-41 sample (MCM41-SU) showed that reaction order equals n = -1 and a rate constant of (k) = 3.9 × 102 (Concentration-2. min-1). A close correlation and agreement was found between the experimental modeling and the theory. Additionally, this current kinetic study showed that water production has no effect on the conversion activity within 10 min from the start of reaction. Besides, further kinetics investigations were performed to ascertain the estimated time for water production based on the conditions applied during the reaction system. It resulted in an average time of 3 min for equilibrium to be reached in the reaction system. It was found that the estimated reaction equilibrium time (t eq ) is within the range from zero to 10 min in agreement with the proposed kinetic model in this work. Finally, it was also observed that a low equilibrium conversion (XAeq) had been obtained in the present work about 0.42 (42%). At a reaction temperature of 60°C (333.15 K) and at one atmosphere, the acetone was shown to exert a vapor pressure of about 113.737 mm Hg. Hence, the overall order of the reaction was determined by the method of initial rates. Similarly, in order to ascertain the dispersion of aluminum, together with its distribution on the surface of a catalyst for a zeolite that has varying molar ratios of silica to alumina as is the case for example with ZSM-5 (35), a mathematical approach is proposed in this study for its calculation.

6.
Bioinformation ; 15(6): 380-387, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31312074

RESUMO

Histone deacetylase (HDAC2) belongs to the hydrolase family and a promising target for cancers. We reported 96 hydroxamic compounds optimized using hydrogen-donors, hydrophobic and electron withdrawing groups followed by molecular docking studies. The optimized compounds show good LibDock score and H-bond interaction in the active site of HDAC2. We selected 20 compounds as the best HDAC2 inhibitors based on the LibDock score, binding energy and hydrogen bonding. ADMET predictions on these compounds show good absorption, BBB penetration and no liver toxicity. We subsequently report four compounds selected as best HDAC2 inhibitors based on the LibDock, binding energy, H-bonding and ADMET properties.

7.
J Pharm Bioallied Sci ; 11(3): 240-247, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31555030

RESUMO

BACKGROUND: Numerous synthetic drugs have been recommended as a remedy for diabetes, but their role in hypoglycemic effects are diverse. The side effects associated with these drugs due to their extended use led scientists to find unconventional medicines with no or little side effects. AIM: This study was aimed at assessment of in vitro antidiabetic activities of methanolic extract of Litsea lancifolia leaves by using 3T3L1 cell line. MATERIALS AND METHODS: The cytotoxic effect of the leaf extract was determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The glucose uptake-inducing capabilities and its correlation with glucose transporter 4 (GLUT4) translocation were measured by flow cytometry in 3T3L1 cells. In addition, the inhibitory effect of L. lancifolia leaf extract on α-amylase activity and α-glucosidase activity was determined by colorimetric methods. RESULTS: Different concentrations of L. lancifolia leaf extract did not show any toxicity on 3T3L1 cells, after the treatment for 24h. On stimulation with leaf extract, 60.22% and 86.26% of 3T3L1 cells showed glucose uptake and GLUT4 expression, respectively. The colorimetric assays showed that the methanolic leaf extract of L. lancifolia has a significant inhibitory effect on the activity of α-amylase enzyme and α-glucosidase enzyme with inhibitory concentration (IC50) value of 248.65 µg/mL and 229.61 µg/mL, respectively. CONCLUSION: On the basis of the results of this study, it is evident that L. lancifolia leaf extract showed promising anti-diabetic effect when compared to the standard drugs metformin and acarbose and was nontoxic to 3T3L1 cells. Thus, it can be further investigated to recommend as a possible alternative treatment in antidiabetic applications.

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