Examinando por Materia "Extraccion (quimica)"

Mostrando 1 - 4 de 4
  • Publicación
    Acceso abierto
    Caracterización y evaluación de quitosano como potencial biomaterial para aplicaciones en ingeniería de tejidos
    (Universidad de San Buenaventura, 2014) Álzate Díaz, Luisa Fernanda; Cuervo Mulet, Raúl Alberto; Valencia Zapata, Mayra Eliana
    In this research the characterization and evaluation of commercial and experimental films of chitosan as a biomaterial for potential applications in tissue engineering was performed. The experimental chitosan was obtained from the cell wall of the fungus Aspergillus niger. This was grown and processed in the facilities of the Universidad San Buenaventura, Cali, Colombia, Instituto Tecnológico de Mérida, Mérida, Mexico, and Centro de Investigación Científica de Yucatán, Merida, Mexico. The methodology is based on a process of basic hydrolysis using 40% NaOH at 95 ° C for 5 hours. Subsequently, an acid treatment was carried out with 10% HCl and then chitosan precipitation using 30% NaOH was made. Chitosans were characterized by infrared spectroscopy (FTIR), nuclear magnetic resonance and thermogravimetric analysis (TGA). Solutions with trifluoroacetic acid / dichloromethane was prepared at 70/30 respectively and both experimental and commercial chitosan 7% w / v. The commercial chitosan is formed by electrospinning, producing films of continuous fibers (of submicron lengths) forming a highly porous three-dimensional membrane. The films were characterized by SEM and SEM-EDX and stress tests.
  • Publicación
    Acceso abierto
    Desarrollo de nanofibras de PVA funcionalizadas con quitosano y obtenidas por lectrohilado para su potencial aplicación en el tratamiento de aguas con cobre
    (Universidad de San Buenaventura, 2016-05) Gómez Campo, Angelica; Osorno Valencia, Isabella; Franco Medina, Edgar
    The wastewater treatment is a very important issue around the world, because if adequate water purification is performed, and reach the human being, could be harmful to health. Water contaminated with different substances or heavy metals, can cause illness and even death. Therefore, this scientific research sought to make membranes or nanometric mats by electrospinning process (electrospinning), with potential use as a filter for water containing copper. The mats are produced from solutions of polyvinyl alcohol (PVA) and Chitosan (CS) as a chelating agent to sequester metal ions, it also added a certain percentage of formaldehyde to prevent solubility in water of PVA. The nanofibers obtained were characterized by assays scanning electron microscopy (SEM), solubility, swelling, gravimetric efficiency, infrared spectroscopy Fourier transform (FTIR), differential scanning calorimetry (DSC) spectrometry.
  • Publicación
    Acceso abierto
    Influencia de la hidroxiapatita (ha) y el metacrilato del 2-(dimetilamino etilo), en las propiedades físicas, mecánicas y biológicas en los cementos óseos acrílicos
    (Universidad de San Buenaventura, 2014) Santacruz Bastidas, Fredy Galileo; Valencia Zapata, Mayra Eliana
    In the present investigation acrylic bone cements were prepared with a solid / liquid ratio of 2/1. The liquid component consisted of methyl methacrylate ( MMA ) , dimethyl - p -toluidine and dimethyl amino ethyl methacrylate ( DMAEM ) as alkaline comonomer ; while the solid component consisted of beads of polymethylmethacrylate (PMMA ) , barium sulfate , and benzoyl peroxide as bioactive hydroxyapatite load. By response surface design effect of co- monomer and bioactive load on the curing properties , physicochemical and mechanical was studied and it was determined that the cement with 1.77 % of 20% DMAEM and HA , had the best combination of the properties studied , so this formulation were made complementary biological assays, this finding has a bio- active character with optimal thermal and mechanical properties ; with which it is inferred that it is feasible to use as filler intermediate agent between the implant and the bone in the area of oral implantology and reconstructive.
  • Publicación
    Acceso abierto
    Obtención de quitosano a partir de desechos del exoesqueleto de camarón tití (xiphopenaeus riveti) para el desarrollo de películas poliméricas plastificadas con glicerina
    (Universidad de San Buenaventura, 2014) López Calvache, Paola Fernanda; Cuervo Mulet, Raúl Alberto; Valencia Zapata, Mayra Eliana
    This paper shows the process of preparation of polymer films based on chitosan and glycerol as plasticizer, chitosan extraction was performed from titi shrimp exoskeleton (Xiphoneus riveti) obtained in the gallery of the city of Buenaventura in the Department Valle del Cauca, following chemical processes, depigmentation, demineralization, deproteinization and deacetylation. Chitosan was characterized by infrared spectroscopy (FTIR), degree of deacetylation by potentiometric titration and solubility tests, etc. With chitosan films were obtained by the slow evaporation process with different concentrations of glycerin which were evaluated physical, mechanical, and antibacterial activity with Bacilius cereus bacteria and Escherichia coli. Dinámica de Investigación