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Dental pulp stem cells (DPSCs) are a new type of mesenchymal stem cells (MSCs) found in the oral cavity with immunomodulation and tissue regeneration capacities. This study determined the impacts of nano-hydroxyapatite (nHA) prepared through Elaeagnus Angustifolia extract (EAE) to enhance the relative expression of immunomodulatory/dentin-pulp regeneration genes in DPSCs. To produce nHA and modified nHA via EAE (nHAEA), the sol-gel technique was used. The functional groups of nanoparticles (NPs), morphological, and optical features were determined using Fourier transform infrared (FTIR), X-ray diffraction (XRD), Scanning electron microscopy (SEM) together with energy-dispersive X-ray analysis (EDAX), and Transmission electron microscopy (TEM). The cell viability was then determined using the MTT method in the presence of various EAE, nHA, and nHAEA concentrations. Target gene expression was quantified using a real-time PCR procedure after treating DPSCs with an optimally non-toxic dose of EAE and NPs. The presence of the HA phase was reported with the XRD and FTIR results. According to the results of SEM and TEM, the rod-like NPs could be fabricated. nHAEAs were found to be characterized with low crystallite size, reduced diameter, lengthier, needle-like, and less agglomerated particles compared with nHA. The real-time PCR results demonstrated that nHAEA remarkably increased the expression of human leukocyte antigen-G5 (HLA-G5), vascular endothelial growth factor (VEGF), dentin sialophosphoprotein (DSPP), and interleukin6 (IL6) genes compared to the nHA group. These findings suggest that nHAEAs might have the potential application in the stemness capability of DPSCs for the treatment of inflamed/damaged pulp.
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Pulpa Dental , Durapatita , Humanos , Durapatita/farmacología , Factor A de Crecimiento Endotelial Vascular/metabolismo , Células Madre , Regeneración , Diferenciación Celular , Dentina , Células Cultivadas , Proliferación CelularRESUMEN
The presence of humic acid compounds in water resources, as one of the precursors of Trihalomethanes and Holoacetic acids, causes health problems for many communities. The aim of this research study was to investigate the photocatalytic degradation efficiency of humic acid using MnFe2O4@TiO2 nanoparticles which produced by green synthesis method. The synthesis of metal nanoparticles using plant extracts and the study of their catalytic performance is a relatively new topic. Many chemical techniques have been proposed for the synthesis of MnFe2O4@TiO2 nanoparticles, but green synthesis has received much attention due to its availability, simplicity, and non-toxicity. The properties of synthesized nanoparticles were determined by SEM, FT-IR, XRD, EDS, and DLS analysis. The results of the study showed that under optimal experimental conditions (pH = 3, nanocomposite dose = 0.03 g/L, humic acid initial concentration = 2 mg/L, and contact time = 20 min), it is possible to achieve maximum degradation of humic acid. Therefore; MnFe2O4@TiO2 nanoparticles have high efficiency for removing of humic acid from aqueous solutions under UV light.
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Nanopartículas del Metal , Nanocompuestos , Sustancias Húmicas/análisis , Espectroscopía Infrarroja por Transformada de Fourier , Corteza de la Planta/química , Agua , Titanio/química , Nanopartículas del Metal/química , Rayos Ultravioleta , Nanocompuestos/química , CatálisisRESUMEN
In this study for the first time, high efficient, eco-friendly and novel Dy2O3/ZnO-Au ternary nanocomposites (Dy/ZnO-AuNCs) were prepared in presence of pomegranate fruit (PF) extract as capping and reducing agents (Dy/ZnO-AuNCs@PF). The influence of various parameters such as basic agents, reducing agents, sonication power, and sonication time were performed to reach the optimum condition. The formation of the products was characterized by FT-IR, HRTEM, XRD, FE-SEM, TEM, EDX and DRS techniques. The XRD and TEM analysis showed that the morphology and crystallite size of nanocomposites were spherical morphology and 85-90 nm, respectively. The obtained Dy/ZnO-AuNCs@PF were investigated as a nanocatalyst for degradation of erythrosine (ES) as anionic dye and basic violet 10 (BV10) as cationic dye under UV and visible light irradiations. The Dy/ZnO-AuNCs@PF exhibited higher photodegradation against ES (89.6%) and BV10 (91.3%) than pure Dy2O3 (63.1% for ES, 66.5% for BV10) and Dy2O3/ZnO (64.5% for ES, 70.8% for BV10) under UV irradiation. It was found that gold nanoparticles have significant effect on Dy/ZnO-AuNCs@PF catalytic performance for decomposition of organic pollutants. In addition, Dy/ZnO-AuNCs@PF showed excellent in-vitro antibacterial activity against A. baumannii, S. aureus and P. mirabilis with MIC and MBC values of (5, 80 mg/ml), (5, 40 mg/ml) and (2.5, 20 mg/ml), respectively. Generally, according to its excellent antibacterial and catalytic activity, Dy/ZnO-AuNCs@PF can be used in biomedical and environmental applications.
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Antibacterianos/farmacología , Disprosio/farmacología , Oro/farmacología , Nanocompuestos/química , Extractos Vegetales/farmacología , Óxido de Zinc/farmacología , Acinetobacter baumannii/efectos de los fármacos , Antibacterianos/síntesis química , Antibacterianos/química , Catálisis , Relación Dosis-Respuesta a Droga , Disprosio/química , Frutas/química , Oro/química , Tecnología Química Verde , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Procesos Fotoquímicos , Extractos Vegetales/síntesis química , Extractos Vegetales/química , Granada (Fruta)/química , Proteus mirabilis/efectos de los fármacos , Staphylococcus aureus/efectos de los fármacos , Relación Estructura-Actividad , Óxido de Zinc/químicaRESUMEN
In this study, zero-valent iron (GnZVI) was synthesized using barberry leaf extract (GnZVI@BLE). The physicochemical properties of the final products were characterized by FT-IR, SEM, TEM, and EDS techniques. The results of TEM analysis showed that the obtained iron zero-valent nanoparticles with a diameter between 20 and 40 nm and shell-core structures were successfully synthesized. The results of FT-IR confirmed the presence of various functional groups. The photocatalytic activity of synthesized nanoparticles was investigated by reduction of hexavalent chromium. Laboratory data showed that the presence of GnZVI@BLE as a nanocatalyst in the photocatalytic process could be reduction the hexavalent chromium (Cr (VI)). Photocatalytic data revealed that, when the dosage of nanoparticles was 0.675 g/L, the reduction efficiency of hexavalent chromium was 100%. The kinetics of the reaction follows a pseudo-second-order equation. The constant of reaction rate was 0.4 at pH 2 and 0.5 g/L concentration of GnZVI@BLE.
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Berberis/química , Cromo/química , Tecnología Química Verde , Hierro/química , Nanopartículas del Metal/química , Extractos Vegetales/química , Catálisis , Oxidación-Reducción , Procesos FotoquímicosRESUMEN
In this study, CoFe2O4@ZnO-CeO2 magnetic nanocomposite (CoFe@Zn-Ce MNC) was successfully prepared by facile sonochemical method for the first time. CoFe@Zn-Ce MNC was obtained by green and cost-effective process in the presence of Crataegus microphylla (C. microphylla) fruit extract. Influence of some parameters like capping agents (C. microphylla, SDS and CTAB), sonication time (10, 30 and 60 min) and sonication power (40, 60 and 80 W) were studied to achieve optimum condition. The as-obtained products were characterized by FT-IR, FESEM, TEM, DRS, VSM, EDS, TGA and XRD analysis. Results showed that high magnetic properties (20.38 emug-1), 70-80 nm size and spherical morphology were unique characteristics of synthesized nanocomposite. Antibacterial activity of CoFe@Zn-Ce MNC was examined against E. coli, P. aeruginoss and S. aureus bacteria. Among theme, S. aureus as gram-positive bacteria showed excellent antibacterial activity. Furthermore, photocatalytic performance of the CoFe@Zn-Ce MNC was investigated by degradation of humic acid (HA) molecules under visible and UV light irradiations. The influence of morphology of products and incorporation of cerium oxide with CoFe2O4@ZnO on photocatalytic activity of CoFe2O4@ZnO was performed. After 100 min illumination, the decomposition of HA pollutant by magnetic nanocomposite were 97.2% and 72.4% under exposure of UV and visible light irradiations, respectively. Also, CoFe@Zn-Ce MNC demonstrated high stability in the cycling decomposition experiment after six times cycling runs.
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Antibacterianos/farmacología , Crataegus/química , Nanocompuestos/química , Extractos Vegetales/química , Antibacterianos/síntesis química , Antibacterianos/efectos de la radiación , Catálisis/efectos de la radiación , Cerio/química , Cerio/efectos de la radiación , Cobalto/química , Cobalto/efectos de la radiación , Compuestos Férricos/química , Compuestos Férricos/efectos de la radiación , Tecnología Química Verde/métodos , Sustancias Húmicas , Fenómenos Magnéticos , Nanopartículas del Metal/química , Nanopartículas del Metal/efectos de la radiación , Pruebas de Sensibilidad Microbiana , Nanocompuestos/efectos de la radiación , Pseudomonas aeruginosa/efectos de los fármacos , Staphylococcus aureus/efectos de los fármacos , Ondas Ultrasónicas , Rayos Ultravioleta , Óxido de Zinc/química , Óxido de Zinc/efectos de la radiaciónRESUMEN
Scientists are interested in biosynthesis of gold nanoparticles owing to their catalytic and biological features. In this research, the extract of Convolvulus fruticosus (C. fruticosus; CFE) extract was applied to synthesize spherical-like gold nanoparticles (CFE@AuNPs). As-prepared CFE@AuNPs was characterized by TEM, FE-SEM, XRD, FT-IR, EDS, UV-Vis and DLS analysis. Identification analysis revealed that the properties of as-prepared CFE@AuNPs with spherical morphology were homogeneous, regular, high dispersibility and low agglomeration. The particle size of biogenic gold nanoparticles (about 35 nm) was obtained using FE-SEM, TEM and DLS techniques. Photocatalytic experiment of CFE@AuNPs determined by degradation of basic violet 10 (BV10), basic blue 9 (BB9) and acid red 51 (AR51) pollutants with percent degradation of 94.3%, 90.2%, 85.4% under UV and 80.6%, 79.8%, 73.3% under visible light irradiation, respectively. As well as, as-prepared CFE@AuNPs illustrated as a significant inhibitory influence against ATCC strain for both gram-positive and gram-negative bacteria. Owing to the antibacterial results, CFE@AuNPs enhanced antibacterial activity against E. coli, A. baumannii, P. aeruginosa, S. aureus, K. pneumonia, P. mirabilis and E. faecalis with MIC of 0.075, 0.075, 0.075, 0.075, 0.15, 0.075 and 0.037 mg/ml, respectively. All in all, results of the findings showed that C. fruticosus capped gold nanoparticles can find applications in the various arena including biological and removal of toxic pollutants for water purification.
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Antibacterianos/farmacología , Convolvulus/química , Oro/química , Nanopartículas del Metal/química , Extractos Vegetales/farmacología , Catálisis , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Microscopía Electrónica de Rastreo , Microscopía Electrónica de Transmisión , Análisis Espectral/métodos , Temperatura , Difracción de Rayos XRESUMEN
BACKGROUND AND PURPOSE: Green nanotechnology is an interesting method for the synthesis of functional nanoparticles. Because of their wide application, they have set up great attention in recent years. OBJECTIVE: The present research examines the green synthesis of Ag and zero-valent iron nanoparticles (AgNPs, ZVINPs) by Feijoa sellowiana fruit extract. In this synthesis, no stabilizers or surfactants were applied. METHODS: Eco-friendly synthesis of Iron and biogenic synthesis of Ag nanoparticles were accomplished by controlling critical parameters such as concentration, incubation period and temperature. Scanning Electron Microscopy (SEM), Transmission Electron Microscope (TEM), Energy-Dispersive X-ray Spectroscopy (EDS), Fourier-Transform Infrared (FT-IR) spectroscopy, X-ray Diffraction analysis (XRD), Dynamic Light Scattering (DLS) and UV-Vis were applied to characterize NPs. The cytotoxicity of NPs was investigated in two cell lines, MCF-7 (breast cancer) and AGS (human gastric carcinoma). A high-performance liquid chromatography (HPLC) analysis was also performed for characterization of phenolic acids in the extract. RESULTS: Both NPs displayed powerful anticancer activities against two tumor cell lines with little effect on BEAS-2B normal cells. Synthesized AgNPs and ZVINPs inhibited the growth of all selected bacteria. Pseudomonas aeruginosa, Proteus mirabilis, Klebsiella pneumonia, Staphylococcus aureus, Enterococcus faecalis, Acinetobacter baumannii and Escherichia coli have been studied in two stages. We initially examined the ATCCs followed by clinical strain isolation. Based on the results from resistant strains, we showed that nanoparticles were superior to conventional antibiotics. DPPH (diphenyl-1-picrylhydrazyl) free radical scavenging assay and iron chelating activity were used for the determination of antioxidant properties. Results showed a high antioxidant activity of scavenging free radicals for ZVINPs and powerful iron-chelating activity for AgNPs. Based on the HPLC data, catechin was the major phenolic compound in the extract. CONCLUSION: Our synthesized nanoparticles displayed potent cytotoxic, antibacterial and antioxidant activities.
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Antibacterianos/farmacología , Antineoplásicos/farmacología , Antioxidantes/farmacología , Feijoa/química , Hierro/farmacología , Nanopartículas del Metal/química , Plata/farmacología , Antibacterianos/química , Antibacterianos/metabolismo , Antineoplásicos/química , Antineoplásicos/metabolismo , Antioxidantes/química , Antioxidantes/metabolismo , Bacterias/efectos de los fármacos , Compuestos de Bifenilo/antagonistas & inhibidores , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Feijoa/metabolismo , Frutas/química , Frutas/metabolismo , Humanos , Hierro/química , Hierro/metabolismo , Estructura Molecular , Picratos/antagonistas & inhibidores , Extractos Vegetales/química , Extractos Vegetales/metabolismo , Plata/química , Plata/metabolismo , Relación Estructura-ActividadRESUMEN
The present study introduces a simple, biocompatible and effective drug delivery system by using mesoporous nanocomposite-based platform. To achieve this goal, mesopourous Fe3O4@SiO2-hydroxyapatite nanocomposite (mFSH) was synthesized by sonochemical process in presence of strawberry fruit extract as capping agent (mFSH-SW). The impact of various factors such as sonication time (5, 15, 30 and 45 min), capping agent (cherry (CH), strawberry (SW), malus domestica (MD), andean blackberry (AB)), pH (10, 11 and 12) and sonication power (30, 60 and 80 W) were investigated to reach optimum condition. To reach high efficiency of drug loading, mFSH was grafted with 3-aminopropyl triethoxysilane (APTES). Uniform, regular and spherical morphology of nanocomposite were specified by field emission scanning electron microscopy (FESEM), X-ray powder diffraction (XRD), vibrating sample magnetometer (VSM), high-resolution transmission electron microscopy (HRTEM), energy-dispersive x-ray spectroscopy (EDX), dynamic light scattering (DLS), nitrogen adsorption/desorption isotherm and Fourier-transform infrared spectroscopy (FT-IR) techniques. The mean pore size, surface area, and pore volume of mFSH-SW were 63.2 m2 g-1, 14.1 nm and 0.24 cm3 g-1, respectively. Sulfasalazine (SLN) loading and release were carried out by various products. The functionalized mFSH-SW showed high adsorption capacity (approximately 59.1 %) for SLN that possesses amino functional groups. The results showed that 100 % of SLN-loaded nanocomposite could be released after 36 h at intestinal conditions (pH = 6.8). In addition, in-vitro and in-vivo toxicity investigations of product were performed with apoptosis/necrosis, XTT and pathology assay, respectively. All in all, unique properties of the nanocomposite including low toxicity, high drug loading, slow release and biodegradable showed that it can be used in biomedical sciences.
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Durapatita , Fragaria , Nanocompuestos , Frutas , Extractos Vegetales , Dióxido de Silicio , Espectroscopía Infrarroja por Transformada de Fourier , SulfasalazinaRESUMEN
In this research, early diagnosis of cardiovascular diseases can reduce their mortality and burden. In our study, we developed a new nano-agent, 99mTc-Dendrimer Glyco Conjugate (99mTc-DGC), and assessed its safety and capability for myocardial viability scan. To develop 99mTc-DGC, we first synthesized the dendrimer and then, glucose has been conjugated. Afterwards, we measured toxicity of the product on normal cells by XTT and apoptosis/necrosis methods. We compared the myocardial viability scan (measured by SPECT and dynamic planar imaging) in two rabbit models, with and without infarction. We also assessed the biodistribution of 99mTc-DGC in rats with no infarction. DGC synthesis was confirmed by Fourier transform infrared (FT-IR), proton nuclear magnetic resonance (1H NMR), liquid chromatography-mass spectrometry (LC-MS), dynamic light scattering (DLS) and static light scattering techniques (SLS). Then radiochemical purity (RCP) was done to present the stability and potential of DGC to complex formation with 99mTc. In vitro cytotoxicity showed nontoxic concentration up to 8 mg/mL. Single Photon Emission Computed Tomography (SPECT) and dynamic planar imaging clearly showed the accumulation of 99mTc-DGC in myocardial. Biodistribution result showed the 2.60% accumulation of 99mTc-DGC in myocardial after 2 h. Our findings indicated 99mTc-DGC to be safe and can accurately diagnose myocardial infarctions at early stages. Human studies to further assess such effects are critical.
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Cromatografía Liquida/métodos , Dendrímeros/química , Glicoconjugados/química , Cardiopatías/diagnóstico por imagen , Espectrometría de Masas/métodos , Compuestos de Organotecnecio/química , Espectroscopía de Protones por Resonancia Magnética/métodos , Espectroscopía Infrarroja por Transformada de Fourier/métodos , Animales , Apoptosis/efectos de los fármacos , Modelos Animales de Enfermedad , Células HEK293 , Humanos , Compuestos de Organotecnecio/farmacocinética , Compuestos de Organotecnecio/farmacología , Conejos , Distribución Tisular , Tomografía Computarizada de Emisión de Fotón ÚnicoRESUMEN
In this work, a cost-effective/green/high-efficient/facile process for the preparation of silver nanoparticles using C. pentagyna (CP-AgNPs) fruit extractas as reducing agent and capping agent was reported. The influence of different parameters including temperature, pH, concentration and time were studied to reach optimum conditions. The as-synthesized CP-AgNPs were characterized using UV/Vis, XRD, SEM, TEM, EDS and DLS analysis. Regular, spherical morphology and homogeneous of CP-AgNPs with a mean particles size of 25-45â¯nm was determined from TEM images. The CP-AgNPs in presence of sunlight catalyzed the degradation of the organic contaminant dyes, rhodmine b (RhB), eosin (EY) and methylene blue (MB) with percent degradation of 85% and 70% and 78%, respectively. In addition, CP-AgNPs exhibit antibacterial activities against seven ATCC strains of bacteria and eight strains of drug-resistant bacteria. Due to the results, CP-AgNPs enhanced antimicrobial potential against S. aureus, E. faecalis, P. aeruginosa, A. baumannii and E. coli with MIC and MBC of (0.11, 7.1⯵g/ml), (0.11, 1.7⯵g/ml), (0.11, 0.22⯵g/ml), (0.11, 0.22) and (0.11, 0.44⯵g/ml), respectively. Generally, CP-AgNPs have excellent potential application for the photocatalytic degradation of organic pollutant and in the development of antibacterial materials.
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Antibacterianos/uso terapéutico , Crataegus/química , Frutas/química , Tecnología Química Verde/métodos , Nanopartículas del Metal/uso terapéutico , Extractos Vegetales/química , Plata/uso terapéutico , Antibacterianos/farmacología , Humanos , Nanopartículas del Metal/química , Plata/químicaRESUMEN
Biogenic synthesis of silver nanoparticles (SNPs) has great attention of scientists, as it provides clean, biocompatible, non-toxic and inexpensive fabrication. In this study, F. sellowiana leaf extract was used for synthesizing SNPs which reduces silver nitrate into silver zero-valent. SNPs were characterized by UV, FTIR, XRD, SEM-EDS, and TEM analysis. They were also examined for their biological activities. The presence of biosynthesized SNPs was characterized by UV-visible spectroscopy and also crystal nature of SNPs was identified with XRD analysis. FT-IR spectrum was used to confirm the presence of different functional groups in the biomolecules which act as a capping agent for the nanoparticles. The morphology of SNPs was explored using SEM and the presence of silver was confirmed by elemental analysis. The size of the nanoparticles was in the range of 20-50 nm determined by TEM. The green synthesized SNPs showed good antibacterial activities against both gram-negative and gram-positive bacteria and also in resistant clinically isolated pathogens. Furthermore, the green synthesized SNPs showed reliable anticancer activity on the gastric adenocarcinoma (AGS) and breast (MCF-7) cancer cell lines with little effect on normal (HFF) cells. The in-vitro antioxidant activity of SNPs showed a significant effect on the scavenging of free radicals and iron chelating activity.
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While cancer is the leading cause of human's deaths worldwide, finding an imaging agent which can detect cancer tumours is needed for cancer diagnosis. In the present study, PEG-citrate dendrimer-G2 was used as a nano-carrier of FITC dye and Iohexol to help passive targeting and uptake of both imaging agents in cancer cells/tumour in vitro and in vivo. Dendrimer was synthesisedand the product characterised using LC-MS, FT-IR, DLS, ELS, AFM, and 1HNMR. After FITC loading into dendrimer, MTT was performed to determine the cytotoxicity of formulation on HEK-293 and MCF-7 cells. In vitro imaging using dendrimer-FITC was done via fluorescent microscope thereafter. Moreover, CT imaging using Iohexol was employed to show the targeting nature and ability of the complex to use as imaging agent in vivo. Data yielded in this study corroborate the notion that the promised dendrimer was synthesised properly and had no toxicity along with FITC on normal cell. Furthermore, CT and fluorescent images showed the targeting nature and imaging ability of Iohexol/FITC loaded dendrimer in vitro and in vivo. Overall, results showed promising characteristics of the novel complexes using dendrimer-G2 both in vitro and in vivo.
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Ácido Cítrico/química , Dendrímeros/química , Diagnóstico por Imagen/métodos , Colorantes Fluorescentes/química , Polietilenglicoles/química , Citratos/síntesis química , Citratos/química , Dendrímeros/síntesis química , Portadores de Fármacos , Fluoresceína-5-Isotiocianato/química , Colorantes Fluorescentes/síntesis química , Células HEK293 , Humanos , Células MCF-7 , Coloración y Etiquetado/métodosRESUMEN
Nd2O3-SiO2 nanocomposites with enhanced photocatalytic activity have been obtained through simple and rapid sonochemical route in presence of putrescine as a new basic agent, for the first time. The influence of the mole ratio of Si:Nd, basic agent and ultrasonic power have been optimized to obtain the best Nd2O3-SiO2 nanocomposites on shape, size and photocatalytic activity. The produced Nd2O3-SiO2 nanocomposites have been characterized utilizing XRD, EDX, TEM, FT-IR, DRS and FESEM. Application of the as-formed Nd2O3-SiO2 nano and bulk structures as photocatalyst with photodegradation of methyl violet contaminant under ultraviolet illumination was compared. Results demonstrated that SiO2 has remarkable effect on catalytic performance of Nd2O3 photocatalyst for decomposition. By introducing of SiO2 to Nd2O3, decomposition efficiency of Nd2O3 toward methyl violet contaminant under ultraviolet illumination was increased.
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In this work, highly photocatalytically active Ho2O3-SiO2 nanocomposites have been designed and applied for decomposition of methylene blue pollutant. Ho2O3-SiO2 nanocomposites have been produced by new, quick and facile sonochemical process with the aid of tetramethylethylenediamine as a novel basic agent for the first time. The effect of the kind of basic agent, ultrasonic time and dosage of Ho source on the grain size, photocatalytic behavior and shape of the Ho2O3-SiO2 nanocomposites have been evaluated for optimization the production condition. FESEM, EDX, FT-IR, DRS, XRD and TEM have been applied to characterize the as-produced Ho2O3-SiO2 nanocomposites. Use of the as-produced Ho2O3-SiO2 nanocomposites as photocatalyst via destruction of methylene blue pollutant under UV illumination has been compared. It was observed that SiO2 has notable impact on catalytic activity of holmium oxide photocatalyst for destruction. Introducing of SiO2 to holmium oxide can enhance destruction efficiency of holmium oxide to methylene blue pollutant under ultraviolet light.
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The ZnCr2O4 nanoparticles were synthesized and characterized by different techniques such as; XRD, SEM, EDS, VSM, TEM and IR. In order to modify the morphology of structures, various alkaline and capping agents were used. For this work TETA, en and NH3 as alkaline agents and salicylaldehyde, N,N'-(bis(salicylidene)-ethylene-1,2-diamine) and SDS as capping agents were employed. The cubic morphology for the ZnCr2O4 nanoparticles were obtained by using TETA and N,N'-(bis(salicylidene)-ethylene-1,2-diamine). When SDS and TETA were used, very uniform spherical zinc chromite nanoparticles with fine grain size were produced. Then on the surface of these nanoparticles, Ag nanoparticles were covered by photodeposition method. For investigation photocatalytic activity of the nanoparticles, several factors such as various azo dyes, temperature, grain size and morphology were investigated. Also by using of ZnCr2O4/Ag nanoparticles prepared polymer based nanocomposite. Results indicate that, nanoparticles can enhance the thermal stability of the PVA matrix.
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In this study, at first, TiO2 nanowire was prepared by an alkaline hydrothermal process. In the following, Gr/Pd/TiO2-NPs and Gr/Pd/TiO2-NWs were synthesized by a combination of hydrothermal and photodeposition methods. The properties of as prepared products were characterized using XRD, FT-IR, SEM, DRS, TEM, ICP-OES, EDS and TGA analysis. SEM results confirmed nanodimension structure for all samples. Also the band gap values obtained using DRS technique suggests that all the samples have semiconductor behavior. Using TGA analysis, the amount of graphene loaded onto the powders was confirmed. Photocatalytic degradation of rhodamine B by TiO2-NWs, Gr/Pd/TiO2-NPs and Gr/Pd/TiO2-NWs nanocomposites was compared under ultraviolet light irradiation. Results confirmed that the Gr/Pd/TiO2-NWs composite show the highest photocatalytic activity due to much higher available surface area of TiO2 substrate in nanowire structure. It is expected that the synthesis of the high surface area TiO2 nanowires, facile photodeposition of palladium into its texture, and simple conversion of GO to graphene during hydrothermal process without using strong reducing agents, could be a suitable rote for preparing different types of carbon based TiO2 nanocomposite photocatalysts.
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BACKGROUND: Atenolol has been used to treat angina and hypertension, either alone or with other antihypertensives. Despite its usefulness, it shows some side effects such as diarrhea and nausea in some patients. A method for slow release of atenolol in intestine is helpful to prevent such side effects. METHODS: A facile co-precipitation microwave-assisted method was used to fabricate mesoporous hydroxyapatite nanoparticles (mHAp). It was then functionalized to have SO3H groups. The synthesized material was used for storage/slow release study of atenolol. RESULTS: Atenolol loaded mHAp shows immediate release of atenolol in pH 8, whileafter functionalizing shows up to ca. 30% release at the beginning. In pH 1, 50% of drug was released after 10 h from AT@mHAp and after 18h the drug was almost completely released.The drug release profiles of functionalized HAp at pH value 1 and 8reveals the complete release of atenolol in intestine pH, while no complete release is observed in stomach environment. CONCLUSION: The aims of this work were synthesis and characterization of mesoporous HAp through the microwave-assisted co-precipitation method and elucidate the underlying drug release capability of mesoporous HAp nanoparticles. The SO3H group was incorporated into the mesoporous HAp and then used as drug delivery carriers using atenolol as a model drug to investigate their drug storage/release properties in simulated body fluid (SBF). Increasing pH value to 8 causes increase in the drug release.