A series of organic compounds were successfully immobilized on an N-doped graphene quantum dot (N-GQD) to prepare a multifunctional organocatalyst for coupling reaction between CO and propylene oxide (PO). The simultaneous presence of halide ions in conjunction with acidic- and basic-functional groups on the surface of the nanoparticles makes them highly active for the production of propylene carbonate (PC). The effects of variables such as catalyst loading, reaction temperature, and structure of substituents are discussed.
View Article and Find Full Text PDFApplying multifunctional nanocarriers, comprising specifically traceable and tumor targeting moieties, has significantly increased in cancer theranostics. Herein, a novel targeted, trackable, and pH-responsive drug delivery system was fabricated based on glucosamine (GlcN) conjugated graphene quantum dots (GQDs) loaded by hydrophobic anticancer agent, curcumin (Cur), to evaluate its targeting and cytotoxicity potential against breast cancer cells with overexpression of GlcN receptors. The biocompatible photoluminescent GQDs were synthesized from graphene oxide through the green and facile oxidizing method.
View Article and Find Full Text PDFA new synthesis strategy was adopted to convert cellulose to a biodegradable sorbent with properties of very high oil absorption and retention capacities, excellent oil-water selectivity, good mechanical strength and recycling ability. The sorbent in form of a hydrophobic/oleophilic nano-structured aerogel was prepared through functionalizing cotton cellulose with low surface energy moieties followed by dissolving and chemically cross-linking the product in an organic medium (DMSO), and freeze-drying. High absorption capacities of 40.
View Article and Find Full Text PDFMater Sci Eng C Mater Biol Appl
January 2019
The unique properties of graphene quantum dots (GQDs) which include high loading capacity, excellent physiological stability, strong photoluminescence, biocompatibility, and facile production make them attractive nanomaterials for biomedical applications. In this work, GQDs have been explored as dual-functional targeted drug carriers and cellular bioimaging agents. The GQDs were conjugated to single chain variable fragment of antibody (scFv), which had been engineered with high affinity (B10) to epidermal growth factor receptor (EGFR), via amide covalent linkages (GQDs-scFvB10).
View Article and Find Full Text PDFThe exceptional chemical and physical properties of graphene oxide (GO) make it an attractive nanomaterial for biomedical applications, particularly in drug delivery. In this work we synthesized a novel, GO-based nanocarrier for the delivery of docetaxel (DTX), a potent hydrophobic chemotherapy drug. The GO was functionalized with transferrin (Tf)-poly(allylamine hydrochloride) (PAH), which provided targeted and specific accumulation to extracellular Tf receptors and stabilized GO in physiological solutions.
View Article and Find Full Text PDFSurface modification of multiwalled carbon nanotubes (MWCNTs) through functionalization could improve the characteristics of these nanomaterials as support for enzymes. Carboxylation of MWCNTs (MWCNT-COOH) has been carried out in this study using the dielectric barrier discharge (DBD) plasma reactor through humidified air. The chemical method was also used for further functionalization of the MWCNT-COOH through which the amidation of the surfaces with either butylamine (MWCNT-BA) or octadecylamine (MWCNT-OA) was performed.
View Article and Find Full Text PDFA model diesel fuel containing 250 ppmw sulfur (as dibenzothiophene) in n-hexadecane was desulfurized at low temperatures in absence of hydrogen, down to about zero ppmwS on a novel adsorbent of well dispersed 3-12 nm Nix-Cu10-x (x=Ni wt%) nanoparticles formed by impregnation on γ-Al2O3 and reduced in H2 at 275 or 450°C. The sorbents were characterized by XRD, TEM-EDX, FESEM-EDS, H2-TPR, TPO, BJH and BET surface area measurement techniques. Effects of various parameters comprising Cu content, reduction and desulfurization temperatures, inhibition by naphthalene, and regeneration of spent sorbents were investigated.
View Article and Find Full Text PDFThe effects of surface acidity and basicity of metal oxide nanoparticles on the thermodynamics of asphaltene adsorption were studied. Three different categories of metal oxides/salts with acidic (WO3 and NiO), amphoteric (Fe2O3 and ZrO2), and basic (MgO and CaCO3) surfaces were synthesized, and their textural, structural, and acid-base properties were characterized. Asphaltenes were extracted from a dead oil sample and characterized by X-ray powder diffraction and Fourier transform infrared spectroscopy.
View Article and Find Full Text PDFVO(x)-MWCNTs nanocomposite was prepared via deposition-precipitation method followed by microwave treatment. Platinum nanoparticles were dispersed via polyol process over the nanocomposite support, and thus, prepared electro-catalyst was employed in methanol electro-oxidation reaction. The electro-catalysts were characterized by means of TGA, XRD, EDS, FESEM, TEM, and H(2)-TPR analysis.
View Article and Find Full Text PDFSimulated by the synthesis of one dimensional hollow nanostructures with significant sensing, electrical, and optical properties, we have successfully synthesized 1D hollow nanostructures of h-MoO3/SnO2 with well-defined multi-side walls. These hollow nanostructured materials synthesized via a hydrothermal method with SnCl2.2H2O as the precursor and h-MoO3 as the template.
View Article and Find Full Text PDFIn this study, we synthesized tetragonal-phase SnO2 with a variety of well-crystallized morphologies as solid microspheres, hollow microspheres and mixture of hollow microspheres and nanosheets via the hydrothermal method. The synthesized samples were characterized with XRD, SEM, and BET. SnO2 hollow microsphere structures have been hydrothermally synthesized by using urea and SnCl2 as raw materials.
View Article and Find Full Text PDFA novel technique of chloride solution combustion synthesis (CSCS) is employed for preparation of SnO2 nanoparticles, using SnCl4 and sorbitol as a novel precursor and a fuel, respectively. Ammonium nitrate is also used as a combustion aid. The solution combustion synthesis is a single-step and simple method for nanoparticles synthesis.
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