Publications by authors named "H E Esparza-Ponce"

Gold nanorods (AuNRs) suspension at various concentrations was added into the sol-gel process to engineer nanostructured europium-doped silica host matrices as light-emitting composites. For this purpose, the samples were prepared following two different routes depending on the chemicals used as dopant and catalyst: (a) Eu(NO)·5HO and HNO, and (b) EuCl·6HO and HCl. In any case, samples adding various concentrations of AuNRs suspension were prepared.

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Silica-Gold Nanostructures (SGNs), composed of a silica core decorated by gold nanoparticles, have the photothermal capacity to transform near-infrared (NIR) wavelengths into heat. This work presents a simple, efficient, and replicable method of synthesis of SGNs and their characterization by: (1) transmission electron microscopy to obtain micrographs of the particles and their corresponding diameter distribution; (2) diffraction patterns showing the amorphous atomic arraignment of the silica and the crystalline atomic arrangement of the gold nanoparticles; (3) zeta potential confirming the stability of the SGNs in a colloidal solution; and (4) thermal images displaying the capacity of SGNs to convert NIR irradiation into heat and their respective increment in temperature. SGNs were synthesized over silica cores with diameters of 63, 83, and 132 nm and decorated with a partial gold shell.

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Gold salts have been used to treat rheumatoid arthritis (RA) since the 1940s, and, with advances in nanotechnology, the use of nanogold provides multiple options for anti-inflammatory therapies. This paper presents the synthesis and characterization of silica-gold nanostructures (SGNs) and their therapeutic effect in collagen-induced arthritis (CIA) in DBA/1 mice. At the end of the treatment, the synovial membranes, kidneys, livers, and spleens were dissected and analyzed by inductively coupled plasma mass spectroscopy (ICP) showing less than 0.

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A Three-Way Catalyst (TWC) contains a cordierite ceramic monolith coated with a layer of AlO, CeZrO and platinoids mixture. Under standard operation, the platinoid concentration decreases, exposing the remaining washcoat structure. After that particle release stage, the sintering process follows where the crystalline CeZrO solution is broken and begins to separate into ZrO and CeO phases.

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Antibiotics are being less effective, which leads to high mortality in patients with infections and a high cost for the recovery of health, and the projections that are had for the future are not very encouraging which has led to consider antimicrobial resistance as a global health problem and to be the object of study by researchers. Although resistance to antibiotics occurs naturally, its appearance and spread have been increasing rapidly due to the inappropriate use of antibiotics in recent decades. A bacterium becomes resistant due to the transfer of genes encoding antibiotic resistance.

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