Ciencias Exactas y Ciencias de la Salud
Permanent URI for this collectionhttps://hdl.handle.net/11285/551039
Pertenecen a esta colección Tesis y Trabajos de grado de las Maestrías correspondientes a las Escuelas de Ingeniería y Ciencias así como a Medicina y Ciencias de la Salud.
Browse
Search Results
- Development for an origami fluidic disc for cell pairing and a spiral chip flow for size-based separation(Instituto Tecnológico y de Estudios Superiores de Monterrey, 2024-06-15) Solorio González, Erick; Aeinehvand, Mohammad Mahdin; mtyahinojosa, emipsanchez; Caballero Robledo, Gabriel; School of Engineering and Sciences; Campus Monterrey; González González, EverardoThe potential of laminated sheets as a novel material for creating lab-on-a-chip (LoC) and centrifugal lab-on-a-disk (LoD) devices allows us to explore a variety of biomedical applica-tions for cell manipulation. Despite their advantages, conventional setups have limitations due to their complex systems and expensive manufacturing methods. This thesis proposes an innovative solution by exploring the de-sign and fabrication of a centrifugal and stationary microfluidic platform that combines the advantages of origami and traditional designs and fabrication techniques. The approach presented in this work leverages the unique properties of origami to create an accessible and low-cost device for prove of concept studies for cell interaction techniques. The presented Origami Fluidic Disc (OFD) fabrication methodology includes cutting readily available materials by a plotter machine, layer folding techniques, followed by their thermal binding. One of the design of the OFDs is a centrifugal microfluidic platform which aims to optimize cell-to-cell interactions, enabling high yield cell pairing for the manipulation of wide range cell populations. In this regard, a 65mm based spinning microfluidic disc with a 40mm circular chamber operating at an optimized spin of 1020rpm enables the formation of a single-cell pairing ring formations consisted of 12,500 10-micron viable cells aligned. This thesis does not stop at demonstration of cell-engineering and the experimental setup for cell pairing. It also explores the integration of a stationary spiral microfluidic chip that contain specially designed 3D micro-grooves to efficiently facilitate particle size-based sepa-ration. The spiral chips involve the fabrication of a 75mm base with and internal channel of four and five spirals, each containing an average of 5 3D-grooves per spiral channel enabling the size-based separation of green and red fluorescent polystyrene beads of 5 and 1 microns of radius, respectively. In general, the presented approaches could potentially expand the accessibility of cell manipulation techniques and reduce rapid prototyping time and costs, by applying high-throughput cell pairing and efficient particle separation within low-cost microflu-idic platform fabrication.
- Fabrication of Chitosan-Alginate Core-Shell Mircogels Incorporated with luminescent Cabron Dots for Biomedical Applications(Instituto Tecnológico y de Estudios Superiores de Monterrey, 2024-06) Macias Frotto, Elioth Daniel; Ray, Mallar; emimmayorquin; Verduzco, Lidia Elizabeth; School of Engineering and Sciences; Campus Monterrey; Masoud, MadadelahiBiopolymer microgels present many opportunities in biomedicine and tissue engineering. Among diverse types of microgels, core-shell microgels are of special significance since they may be designed to have a solid core surrounded by liquid-like shell or vice-versa and can be made responsive to external stimuli. Under suitable stimulus (e.g. pH or temperature of a solution containing the microgels) the outer shell may be diluted, thereby releasing the core’s material. Such strategies provide promising possibilities for controlled drug delivery and other biological applications. Additionally, nanoparticles having different functionalities can be embedded in these microgels to enhance or tune their overall properties, thereby making them amenable for variety of applications. In this investigation we develop a novel method to produce chitosan-sodium alginate (CS-SA) core-shell microgels in a single step process using a specially designed high throughput centrifugal microfluidic device (HTCMD). We subsequently incorporated nitrogen functionalized graphene quantum dots (NGQDs) in the core-shell microgels which render them luminescent under UV excitation and are expected to enhance the physical and biological characteristics of the hydrogel microspheres. Initial part of this study was focused on designing and fabricating a microfluidic device that could generate core-shell microgels with controllable geometry and sizes. After several attempts with planar structures we converged on a 3D printed multichannel cylindrical HTCMD that could produce core-shell structures with desired control over size and shape. An analysis of the of microgels generated using the specially designed HTCMD was carried out in order to develop an understanding of the ways in which characteristics of the device such as the diameter of the nozzle and the rotating velocity influence the size, shape, and homogeneity of the generated microparticles. Using a nozzle diameter of 310 µm we could obtain core-shell microspheres having an average diameter of 444 µm at 2500 rpm. On the other hand, a variation of angular velocity between 900 to 2500 rpm allowed us to generate microspheres with average diameters varying between 1500 to 400 µm depending on the nozzle diameter. Following successful fabrication of the HTCMD and controlled generation of spherical core-shell microgels, we investigated the structural, compositional and optical properties of the microgels using a variety of techniques. Fourier transform infrared spectroscopy (FTIR) spectra of the as-prepared core-shell microgels for different concentrations of CS and SA and for the NGQD incorporated microgels revealed that the overall bonding architecture is strongly dependent on the concentrations of CS and SA and is marginally affected by the presence of NGQDs. X-ray diffraction (XRD) of NGQD, CS-SA core-shell microgels and the NGQD incorporated CS-SA particles reveal signatures of crystallinity in all the three samples although sharp crystalline features are not present in any of the samples. In case of NGQD this is attributed to the nanometric size of the crystalline domains while in CS and SA samples the presence of amorphous constituents dominate. Scanning electron microscopy (SEM) alongside brightfield microscopy showed the formation of distinct core-shell interface between CS and SA core-shell structure. UV-vis absorption spectra of all the samples exhibit standard absorption characteristics suggesting the formation of structures with desired electronic transitions. The NGQDs demonstrate excellent room temperature photoluminescence (PL) emission with a PL peak at 444 nm for an excitation of 350 nm. The CS SA core-shell particles exhibit a very weak room temperature PL but following NGQD incorporation their emission is completely defined by the characteristics of the NGQDs. The size and shape controlled, luminescent hydrogel core-shell microspheres have immense potential applications in the fields of drug delivery and tissue engineering. This work proposes a simplified method for the synthesis of microgels by utilizing the pH-dependent sol-gel transition qualities of chitosan, the ionic crosslinking capabilities of alginate. The simplicity of the centrifugal microfluidic platform utilized in the research make it possible to exert exact control over the architecture of the microgel, which in turn promotes a synthesis process that is both easy and extremely effective.
- Development, optimization and evaluation of a microfluidic, paper-based, analytical device for glucose and uric acid detection: a proof-of-concept(Instituto Tecnológico y de Estudios Superiores de Monterrey, 2023-06-01) González Torres, Luis Fernando; González González, Mirna Alejandra; puemcuervo, emimayorquin; Zavala Arcos, Judith; Aguilar González, Cristóbal Noé; School of Engineering and Sciences; Campus Monterrey; Ortíz Martínez, MargaritaGlucose and uric acid are systemic metabolites of clinical interest in patients with obesity. Glucose plays a crucial role in multiple metabolic processes and is an indicator of pathological conditions in obesity-related diseases such as diabetes. Additionally, untreated hyperuricemia, defined as serum uric acid levels exceeding 400 µM, is associated with obesity and can lead to the development of conditions such as gout and kidney dysfunction. Therefore, regular testing of glucose and uric acid levels can be relevant as preventive measures for screening and monitoring purposes. Within the field of point-of-care testing, microfluidic, paper-based analytical devices offer several advantages, including compact size, portability, affordability, biocompatibility, and simplicity. Enzymatic colorimetry serves as an effective detection method due to its low cost, rapid response time, and high selectivity. Furthermore, no complex equipment is required, and a smartphone can be employed to capture the color response for analysis in ImageJ. As a microfluidic pattern generation method, selective wet etching stands out given its fast, simple, and inexpensive procedure. In this work, a microfluidic, paper-based, colorimetric device is developed to detect glucose and uric acid in solution. Trimethoxy(octyl)silane was used to turn the surface of the paper hydrophobic, and NaOH was used as the etching agent to generate the hydrophilic pattern. The detection limits for glucose and uric acid were 0.02 and 0.04 mM, respectively. Additionally, the glucose and uric acid assays exhibit linear responses encompassing the physiological range found in saliva and serum. In the future, this device could be further adapted and validated for the detection of glucose and uric acid in relevant biofluids.