Ciencias Exactas y Ciencias de la Salud
Permanent URI for this collectionhttps://hdl.handle.net/11285/551014
Pertenecen a esta colección Tesis y Trabajos de grado de los Doctorados correspondientes a las Escuelas de Ingeniería y Ciencias así como a Medicina y Ciencias de la Salud.
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- Theoretical studies for the development of detection mechanisms for tamoxifen and derivative metabolites(Instituto Tecnológico y de Estudios Superiores de Monterrey, 2022-12-08) Santamaría García, Vivian Janeth; SANTAMARIA GARCIA, VIVIAN JANETH; 815010; Bonilla Ríos, Jaime; puemcuervo, emipsanchez; Aguirre Soto, Héctor Alan; Espinoza Martínez, Adriana Berenice; Pablo Pedro, Ricardo; School of Engineering and Sciences; Campus Monterrey; Palma Anda, Julio L.Tamoxifen is an estrogen receptor antagonist designated as the main therapy for treating and preventing breast cancer, which has been identified as a major public health concern. Identifying and quantifying tamoxifen and its main by-products in blood serum are essential indicators to predict the treatment evolution and prospective success rate. The gold standard of such quantification is based on spectrometry and chromatography techniques. However, since they are highly specialized and centralized techniques, they are not accessible to entire public clinical and health areas. Alternatives to current standards to assess tamoxifen therapy have been identified as an important need. Therefore, this work is aimed to provide an identification and detection mechanism to inspire the development of nanosensors with the ability to differentiate and quantify tamoxifen and its main derivatives. This goal is challenging since tamoxifen, and its metabolites share their chemical composition and conformational arrangement to a great extent. This work addresses the problem from a theoretical perspective, applying computational chemistry tools within the molecular electronics framework. We focused on finding differentiation parameters based on the fundamental charge transport properties when tamoxifen and derivatives are implemented as the central molecule of a single molecular junction. We applied the density functional theory (DFT) to characterize individual molecules as isolated systems. The charge transport calculations were implemented using density functional theory with the non-equilibrium Green’s functions (DFT-NEGF). We explored the rectification and bistable switching behavior of different systems, including tamoxifen and derivatives, to develop dual-task molecular devices that, besides pure electronics performance, have parallel sensing applications. We expect that the resultant differentiation mechanism of this thesis project will inspire the development of new technologies that can ease the monitoring of tamoxifen treatments for all.
- Comparing the rheological behavior and the electrical properties of CNT-PP copolymer composites obtained by two compounding methods: direct addition and dilution of a masterbatch(Instituto Tecnológico y de Estudios Superiores de Monterrey) Palacios Aguilar, Erika; Bonilla Ríos, Jaime; tolmquevedo; Medina Medina, Dora Iliana; Monsiváis Barrón, Alejandra Julieta; Cortés Rodríguez, Leonardo Federico; School of Engineering and Sciences; Campus Monterrey; Sánchez Fernández, José AntonioComposites of multiwall carbon nanotubes (CNT) at 1, 2, and 3 wt.% on a propylene-ethylene random copolymer matrix were prepared by melt compounding CNT powder and by dilution of a commercial polypropylene masterbatch. While the shear viscosity shows similar behavior for both dilution modes, the differences in their elastic properties clearly show the addition method's effect, and the masterbatch's presence. This also indicates the relevance of having a difficult to mix masterbatch to enhance the elongational viscosity of the composites for free wall applications such as fiber spinning and blown film. On the other hand, the 2 and 3 wt.% CNT composites from both addition modes have similar electrically conductive behavior, with values near the semiconductors' range. TEM and SEM images show different states of dispersion for each source of CNT. The morphology observed in those images is the simplest explanation for the differences in the elastic properties of the molten composites due to the filler incorporation processes used.