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Ítem Synthesis, Characterization And Application In Controlled Drug Release Of Chitosan Hydrogels Obtained From Aspergillus Niger.(European Polymer Federation, 2011-06-26) XII Congress of the Specialized Group of PolymersNora Elena Valderruten Posso, PhD Universidad del país Vasco, 2001. En Ciencias Químicas, Maestría Universidad del Valle, Posgrado Universidad del Valle en Biología Química, profesora de tiempo completo de la Universidad Icesi del Departamento Académico Ciencias Químicas de la Facultad de Ciencias Naturales y miembro del comité asesor, - trabajps dirigidos/tutorias- trabajos de grado de pregrado, jurado de comité evaluación- miembro del consejo de la Facultad de Ciencias Naturales y coordinadora de cursos de Química Orgánica. Sus trabajos de investigación y desarrollo en la obtención de polimeros biodegradables apartir de ácido grasos de origen vegetal, obtención de materiales compuestos Core-Shell mediante inmovilizacion de catalizadores metalogénicos, obtención de materias polimetricos inteligentes a partir de un subproducto industrial con potencial en la industria farmacéuticas y otras. Synthesis, Characterization And Application In Controlled Drug Release Of Chitosan Hydrogels Obtained From Aspergillus Niger.Ítem Synthesis and characterization of chitosan hydrogels cross-linked with dicarboxylic acids(Elsevier, 2014-11-01) Zuluaga, Héctor FabioChitosan hydrogels cross-linked with dicarboxylic acids were prepared. Succinic, glutaric and adipic acid were used as cross-linking agents, the goal being to compare the effect of the length of the chain on the behavior of the material obtained. The swelling properties were studied at different pHs and temperatures, and it was discovered that these properties depend particularly on the pH of the environment. Creep-recovery and stress-relaxation studies were performed to determine mechanical properties and the chitosan/succinic acid hydrogels exhibited a completely viscous behavior. Thermal studies were carried out using differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). DSC results revealed that the materials obtained are completely amorphous. Acetaminophen was used as a positive control for the release kinetics studies. Upon fitting the results to a specific mathematical model, it was determined that the release process is controlled by diffusion and relaxation of the polymer network.Ítem Effect of the synthetic method on the catalytic activity of alumina: Epoxidation of cyclohexene(2015-02-01) Valderruten Posso, Nora ElenaAl2O3 was prepared from different inorganic precursors via the Pechini method and compared with Al2O3 prepared by the sol–gel method. Structural characterization of these materials was carried out by FTIR, X-ray diffraction (XRD), N2 adsorption at −196°C and transmission electron microscopy (TEM). The solids were tested in the epoxidation of cyclohexene and a difference in their catalytic activities was observed. The characterization results indicate that the samples prepared by Pechini have a mixture of γ-alumina and boehmite, a condition favoring catalytic activity, whereas the sol–gel sample is less crystalline due to higher boehmite content. These results indicate that both the nature of the precursor and the method of synthesis strongly affect the catalytic activity of Al2O3.Ítem Extraction of chitosan from Aspergillus niger mycelium and synthesis of hydrogels for controlled release of betahistine(Elsevier, 2015-06-01) Valderruten Posso, Nora ElenaChitosan was extracted from the fungus Aspergillus niger, an alternative source of chitin that is widely available as a byproduct of the industrial production of citric acid. Chitosan with deacetylation degree (DD) of 73.6% was characterized by elemental analysis, capillary viscometry (molecular weight of 1.9×105g/mol), Fourier transform infrared (FTIR), nuclear magnetic resonance (1H NMR, 13C NMR and 15N NMR) spectroscopies, differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). Fungal chitosan was crosslinked with glutaraldehyde and glutaric acid to obtain hydrogels. Chitosan hydrogels were characterized by FTIR and by scanning electron microscopy (SEM), which showed that these materials have irregular, polydisperse, and interconnected pores. Kinetic studies of the release of betahistine from the swollen hydrogels showed a Fickian diffusion mechanism. Finally, hydrolytic degradation of chitosan hydrogels under simulated physiological conditions (pH 7.4 and 37°C) was investigated as well as in vivo biocompatibility tests using New Zealand white rabbits as animal models.Ítem Síntesis y caracterización de hidrogeles interpenetrados de quitosano/PNIPA(Universidad Icesi, 2012-08-29) Valderruten Posso, Nora Elena; Ruiz Durantez, Eduardo; Katime, Issa A.; Agudelo, JonathanUna red interpenetrada (IPN) consiste en la combinación de dos redes poliméricas diferentes, sin que haya enlaces covalentes entre ellas; de esta forma se consigue una mezcla física que contiene polímeros entrecruzados. Este tipo de polímeros se prepara por el entrecruzamiento simultáneo o secuencial de dos sistemas diferentes y genera materiales que exhiben las propiedades de los dos componentes. El quitosano es un polímero biodegradable, biocompatible y sensible al pH del medio. Por otro lado, la Poli(N-isopropilacrilamida) es un polímero termosensible.Ítem Síntesis y caracterización de materiales absorbentes interpenetrados a partir de polímeros sensibles al pH y temperaturas.(Universidad Icesi, 2011-11-00) Ruiz Durantez, Eduardo; Valderruten Posso, Nora Elena; Valverde, J.D.; Zuluaga, F.Chitosan hydrogels cross-linked with dicarboxylic acids were prepared. Succinic, glutaric and adipic acid were used as cross-linking agents, the goal being to compare the effect of the length of the chain on the behavior of the material obtained. The swelling properties were studied at different pHs and temperatures, and it was discovered that these properties depend particularly on the pH of the environment. Creep-recovery and stress-relaxation studies were performed to determine mechanical properties and the chitosan/succinic acid hydrogels exhibited a completely viscous behavior. Thermal studies were carried out using differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). DSC results revealed that the materials obtained are completely amorphous. Acetaminophen was used as a positive control for the release kinetics studies. Upon fitting the results to a specific mathematical model, it was determined that the release process is controlled by diffusion and relaxation of the polymer network.Ítem Bioeconomía en acción en la COP16: conectando mentes, cosechando soluciones(Universidad Icesi, 2025-10-01) Caicedo Ortega, Nelson H.; Álvarez Vasco, Carlos; Díaz Soto, Bernardita; Orozco Holguín, Jorge Leonardo; Erazo Londoño, Juan Pablo; Burgos Salamanca, Diego Armando; Calberto Sánchez, Germán Andrés; Giraldo Cuartas, Carlos Julián; Ramírez Navas, Juan Sebastián; Valderruten Posso, Nora Elena; Vélez Rolón, Adela; Pulido López, Alejandra; Morales Vera, Rodrigo; Hernández, Camila; Mamani, Maribel; Moraga, Marcelo; Barrera, Francisca; Ríos, Hernán; Amaro, Javiera; Meza, Nirma; Ariza Marín, Leidy Johana; Saavedra Martínez, Sebastián; Gaviria, Maria Isabela; Flórez Laiseca, Adriana María; Yepes Calderón, Fernando; Imbachi Chavez, Richard Marcelo; Luligo Montealegre, Wilmer E.; Prado Alzate, Santiago; Serna Cock, Liliana; Ayala Aponte, Alfredo; Tirado, Diego F.; Luna, Andrés; Beltrán Velasco, José Daniel; Villegas Torres, María F.; Salazar Sánchez, Paula Andrea; Osvaldo Villa, Abel; Humberto Gonzales, Carlos; Trujillo, Mónica; López Rodas, Santiago; Pulgarín Vasco, Juan Diego; Entre otros....La bioeconomía emerge como un faro de innovación y sostenibilidad en la encrucijada de la ciencia y la economía, una fuerza transformadora que impulsa la reinvención de nuestras industrias y la revitalización de los ecosistemas. Este modelo socioeconómico no solo enfatiza la producción sostenible basada en el conocimiento y uso de recursos biológicos, sino que subraya la importancia de establecer sistemas productivos alineados con los límites ambientales de nuestro planeta. Invitamos al lector a sumergirse en las valiosas contribuciones, cuyos esfuerzos y conocimientos enriquecieron significativamente el Segundo Congreso Internacional de Bioeconomía. En este libro encontrarán los resúmenes de las presentaciones en modalidad oral y poster para las cuatro líneas y su lectura promete inspirar acciones concretas que conduzcan hacia un futuro próspero y equitativo. Que estas páginas sean testimonio del compromiso colectivo por transformar nuestras sociedades en comunidades sostenibles, impulsadas por la bioeconomía.