Fe nanoparticles and branched nanostructures of iron oxide were synthesized by chemical reduction in aqueous phase. The mechanism of formation of iron oxides as a function of the amount of surfactant employed during the synthesis process was studied. Specifically Fe, Fe2O3, and Fe3O4nanoparticles were obtained. The oxidation of Fe to Fe3O4and finally to Fe2O3was carried out by oxidative etching process, decreasing the amount of stabilizer agent. The structures obtained were characterized by high resolution (HRTEM) and scanning/transmission (STEM) electron microcopies, energy dispersive spectroscopy (EDS), and optical spectroscopy (UV-Vis and IR).

This study is aimed at investigating the structural and morphological characterization of natural and modified zeolite obtained from the state of Oaxaca (Mexico). Iron nanoparticles were used for the zeolite modification. The iron nanoparticles were loaded on the zeolite surface by homogeneous nucleation. Adsorption kinetic models of pseudo first and second order were surveyed. The characterization of pristine and modified zeolite was performed by Fourier transform infrared (FTIR), transmission electron microscopy (TEM), and X-ray diffraction (XRD). From the results, three main phases were identified: clinoptilolite, mordenite, and feldspar. We could also determine the adsorption capacity of the zeolites by means of adsorption kinetic models.

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Nanoparticles of metals can be toxic to bacteria, showing biocidal activities at low concentrations. Metal, oxide, or compounds based on copper are applied like antimicrobial agents. The capacity of integration of metallic nanoparticles in polymer matrices has improved the antimicrobial behavior, resulting in the search for composites with increased bactericidal properties. A polycaprolactone (PCL) film polymer with copper oxide nanoparticles (CuONPs) was prepared. Dynamic light scattering analysis showed the sizes from 88 to 97 nm of CuONPs. Scanning electron microscopy (SEM) revealed CuONPs with semispherical shapes with diameter 35 nm. The prepared PCL-CuONPs exhibited a nanoporous structure by SEM. The antibacterial applicability of the composite was evaluated to determine the minimum inhibitory concentration in 6 different bacteria and the experimental tests were carried by disk diffusion and spectrophotometric methods. The PCL-CuONPs exhibit a considerable antibacterial effect in gram-positive bacteria in contrast to gram-negative bacteria. The preparation of PCL-CuONPs was simple, fast, and low cost for practical application as wound dressings.