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[This retracts the article DOI: 10.1039/C7RA11763A.].
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The present paper is focused on a simple and economical route to synthesize the organic template-free hierarchical pure and M (Cu, Ni)-modified ZSM-5 zeolites (1%, 3% and 5%) using hydrothermal treatment in the presence of silica rich rice husk ash and its application studies through the evaluation of their anti-cancer activity on A459 human lung epithelial cancer cell lines. The physical properties of the samples were characterized by X-ray diffraction, Fourier transform infrared spectroscopy, high resolution scanning electron microscopy, high resolution transmission electron microscopy, N2 adsorption/desorption techniques and thermogravimetric analysis respectively. These metals modified hierarchical ZSM-5 zeolites showed considerable in-vitro anticancer efficiency towards human lung cancer (A549) cell lines through (3-(4, 5-dimethyl thiazolyl)-2, 5-diphenyl tetrazolium bromide) MTT assay. Among the all M (Cu, Ni)-modified ZSM-5 zeolites, 5% Cu-ZSM-5 zeolites showed higher potential cytotoxicity against A459 cell lines. The possible mechanism was explored from the fundamental signaling pathways of cell death by hierarchical metal modified ZSM-5 zeolites in A459 human lung epithelial cancer cell lines. Finally, our experimental results revealed that the organic template-free hierarchical pure and M (Cu, Ni)-modified ZSM-5 zeolites have significant anti-cancer mediating action by inducing oxidative stress to intercede DNA damage and can be considered as a potential applicant in the biomedical field.
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Antineoplásicos/química , Cobre/química , Níquel/química , Dióxido de Silício/química , Zeolitas/química , Células A549 , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Dano ao DNA/efeitos dos fármacos , Humanos , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Nanopartículas/química , Nanopartículas/toxicidade , Nanopartículas/ultraestrutura , Oryza/química , Oryza/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios XRESUMO
[This corrects the article DOI: 10.1098/rsos.171430.].
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The theme of this work is to highlight the significance of green plant extracts in the synthesis of nanostructures. In asserting this statement, herein, we report our obtained results on the synthesis of hexagonal CdSe nanorods preferably oriented along (0002) plane through henna leaf extract-mediated reaction along with a discussion about the structural, morphological and optical properties of the synthesized nanorods. The possible mechanism for the synthesis of CdSe nanorods was explored. The formation of nanorods along (0002) plane was confirmed by the relatively high intensity of the (0002) peak in X-ray diffraction pattern. To account for the experimentally realistic condition, we have calculated the surface energies of hexagonal CdSe surface slabs along the low indexed (0002), [Formula: see text] and [Formula: see text] plane surfaces using density functional theory approach and the calculated surface energy value for (0002) surface is 802.7 mJ m-2, which is higher than [Formula: see text] and [Formula: see text] surfaces. On realizing the calculated surface energies of these slabs, we determined that the combination of [Formula: see text] and [Formula: see text] planes with lower surface energies will lead to the formation of CdSe nanorods growth along (0002) orientation. Finally, we argue that the design of new greener route for the synthesis of novel functional nanomaterials is highly desired.
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Hierarchical ordered ZSM-5 zeolites were successfully synthesized by a template-free hydrothermal treatment using rice joints ash as the source of silica. The formation of hierarchical ordered ZSM-5 zeolites and its physicochemical properties were investigated systematically. The mineralogical phases, morphology, surface area and porosity, acidity and thermal stability of the synthesized hierarchical materials were investigated using XRD, FT-IR, HR-SEM, N2 adsorption-desorption (BET) analysis, NH3-TPD and TGA/DTA analysis. The excellent catalytic activity of hierarchical ordered ZSM-5 zeolites (150 °C) was revealed in the selective oxidation of toluene to the corresponding benzaldehyde with 82% conversion and 94% selectivity. The material was evaluated for the oxidation of toluene in the presence of H2O2 as the oxidizing agent and 1,4-dioxane solvent. The obtained results noted that the material was highly active, stable and can be recycled at least four times without a loss of catalytic efficiency. The crystallization was carried out in an autoclave for 5 days maintained at a temperature of 150 °C for the transformation of RJA into hierarchical ZSM-5 zeolite structure as well as to achieve high crystallinity.
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Tricobalt tetraoxide (Co3O4), a spinel-structured nanoparticle which possesses mixed oxidation states, has been synthesized via a Punica granatum (P. granatum, pomegranate) seed extract-mediated green reaction and has been investigated for its superior catalytic activity in three applications, which include (i) photodegradation of textile dye effluents (TDE) collected from the dyeing industry, Tiruppur, Tamil Nadu, India, (ii) catalytic hydrogenation of nitro-aromatic pollutants such as 4-nitrophenol and 4-nitroaniline, and (iii) antibacterial potential in biomedical applications. Prior to the application studies, the synthesized Co3O4 spinel nanoparticles (Co3O4-NPs) were characterized by well-known established techniques such as X-ray diffraction (XRD), high resolution transmission electron microscopy (HRTEM), energy dispersive X-ray analysis (EDX), diffuse reflectance spectroscopy (DRS), photoluminescence spectroscopy (PL), and Raman and FT-IR spectroscopies. We have also discussed the probable mechanism and kinetic studies of the catalytic activity of the Co3O4-NPs. Finally, we concluded that the design and development of novel, economic and green synthesis-mediated catalysts such as Co3O4-NPs can exhibit efficient catalytic activity in diverse fields, which is necessary for environmental remediation.
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The present work describes the successful synthesize of spinel magnetic ferrite Mn1-xNixFe2O4 (x=0.0, 0.1, 0.2, 0.3, 0.4 & 0.5) nanoparticles via a simple microwave combustion method which was then evaluated for its photocatalytic activity in the degradation of indigo carmine (IC) synthetic dye, a major water pollutant. Our results reveal that the synthesized of Ni2+ doped MnFe2O4 nanoparticles possess well-crystalline pure cubic spinel phase, exhibit excellent optical and magnetic properties. Further, the photocatalytic performance of the synthesized nanoparticles at different concentration ratios of Ni2+ ions was monitored by photocatalytic degradation of indigo carmine synthetic dye under UV (λ=365nm) light irradiation. In order to get maximum photocatalytic degradation (PCD) efficiency, we have optimized various parameters, which include catalyst dosage, initial dye concentration, pH and Ni2+ dopant content. It was found that the reaction was facilitated with optimum catalyst dose of 50mg/100mL, high dye concentrations of 150mg/L and acidic pH and among all the synthesized samples, Mn0·5Ni0.5Fe2O4 exhibit superior performance of photocatalytic activity on the degradation of indigo carmine synthetic dye. These results highlighted the potential use of effective, low-cost and easily available photocatalysts for the promotion of wastewater treatment and environmental remediation. In addition, the antibacterial activity of spinel magnetic Mn1-xNixFe2O4 nanoparticles against two Gram positive bacteria (Staphylococcus aureus and Bacillus subtilis) and two Gram negative bacteria (Pseudomonas aeruginosa and Escherichia coli) was also examined. Our antibacterial activity results are comparable with the results obtained using the antibiotic, streptomycin.
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Antibacterianos/farmacologia , Nanopartículas Metálicas/química , Fotólise , Antibacterianos/química , Bactérias/efeitos dos fármacos , Cristalografia por Raios X , Luminescência , Magnetismo , Testes de Sensibilidade Microbiana , Microscopia Eletrônica de Varredura , Difração de Raios XRESUMO
Pure and M-doped (Ba, Ce, Mg) ZnO spherical nanoparticles are synthesized by a simple low temperature co-precipitation method, and were characterized by X-ray diffraction (XRD), high resolution scanning electron microscopy (HR-SEM), and high resolution transmission electron microscopy (HR-TEM). The XRD results showed the formation of single phase ZnO with wurtzite crystal structure and the electron microscopic studies supported the validity for the formation of pure and M-doped (Ba, Ce, Mg) ZnO spherical nanoparticles. Photocatalytic degradation (PCD) of 2,4,6-trichlorophenol, a potent endocrine disrupting chemical in aqueous medium was investigated by both pure and M-doped (Ba, Ce, Mg) ZnO spherical nanoparticles under UV-light irradiation. The influence of the metal dopants on the structure and photocatalytic (PC) activity of ZnO was investigated systematically. Furthermore, the effect of different parameters such as 2,4,6-trichlorophenol concentration, photocatalyst amount, pH and dopant wt% on the resulting PC activity was investigated. The kinetics of the photocatalytic degradation of 2,4,6-trichlorophenol was found to follow the pseudo-first order reaction, and it was established that Ba-doped ZnO is photocatalytically more active than the other photocatalysts.