Mostrando 1 - 4 Resultados de 4 Para Buscar 'Elgegren, M', tiempo de consulta: 0.01s Limitar resultados
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artículo
Sacha inchi oil is rich in essential and non-essential fatty acids and other types of bioactive agents like tocopherols and polyphenolic compounds, which are very well-known antioxidants. In this study, the encapsulation of sacha inchi oil in alginate (AL) and chitosan (CS) nanoparticles was achieved with the assistance of high-intensity ultrasound. Nanoemulsion is the most effective delivery and high stability system for lipophilic bioactive agents. Chitosan and surfactant concentrations were varied to study their effect on particle formulations. Size, zeta-potential, polydispersity, and stability of particles were determined in time to optimize the preparation conditions. Sacha inchi oil encapsulated in AL-CS nanoparticles showed a higher loading efficiency and stability for short and long periods compared with other vegetable oils such as olive and soybean. Also, because of the types ...
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artículo
In this research, the nanostructured alginate (AL) membranes were prepared with natural bioactive compound, Cat's claw (Uncaria tomentosa) extract (UT). UT is broadly used as an anti-inflammatory agent and the effect on the treatment of Rheumatism was proved by many scientists. For this reason, we added this bioactive compound in the process of AL membrane formulation to improve the biological activities. 2-dimentional (2-D) and 3-dimentional (3-D) AL membranes were prepared with and without addition of UT extracts. 3-D AL membranes were prepared using ultrasound with high intensity. The wettability of AL membranes depending on the concentration of AL was studied by measuring contact angle and surface energy. Stabilization agent, poloxamer 407, was used to improve the stability of AL nanoemulsion. The effects of UT in 3-D AL membranes were studied by measuring swelling behavior and conta...
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This research was carried out by the Research Group of Materials Modification at PUCP. The authors would like to acknowledge the Pontificia Universidad Católica del Perú PUCP and its funding office DGI-PUCP (project 2013-0061) for providing funds to the project within which this work was developed. The forth author would also like to thank the fellowship funding for postgraduate studies by CONCYTEC, PERU (Contract N° 012-2013-FONDECYT). Finally, the authors thank the Soils Laboratory of the Civil Engineering Department at PUCP for the availability of their installations and equipment, and Manuel Otero, for providing the carrageenan extract for this study.
4
artículo
The study investigates the feasibility of using chitosan biopolymer as an admixture, or as an external coating, for earthen constructions to improve their resistance in two components: water induced degradation and key mechanical properties. The resistance to water induced degradation was evaluated in terms of contact angle and drip erosion tests, while the influence on mechanical properties was measured through compressive, tensile and three-point bending tests. The results indicate that the use of low concentrations of chitosan can improve significantly the performance in the two components and therefore was found to be a promising treatment for new or existing construction.