Engineering Commons^™

Microfluidically Reconfigurable Millimeter-Wave Switches, Antenna Arrays And Filters With Fast-Actuation Using Movable Metallized Plates And Integrated Actuation, Enrique J. Gonzalez Carvajal

USF Tampa Graduate Theses and Dissertations

Microfluidic reconfiguration of microwave devices has emerged as a potentially attractive alternative to integrated semiconductor (ICs/MMICs) and microelectromechanical systems (MEMS) based technologies. On the one hand, MMICs suffer from low power handling capabilities, high IL, non-linear effects, and elevated costs; on the other hand, MEMS are limited by their complex packaging requirements, and relatively low reliability from stiction-based effects. However, microfluidic reconfiguration provides low insertion loss (IL) due to its mechanical nature and it is not limited by power saturation effects. These attributes are especially valuable for applications at mm-waves, potentially reducing costs and increasing power efficiency capabilities. Microfluidic reconfiguration …

Simulation And Optimization Of A Sheathless Size-Based Acoustic Particle Separator, Shivaraman Asoda

USF Tampa Graduate Theses and Dissertations

Standing surface acoustic waves (SSAW) have been widely used for sorting of cells and particles. However, the major challenges faced with the acoustic driven separation process is the need for an optimized setup to achieve effective separation and the range of particles that can be separated. In this thesis, a custom simulation model is studied to investigate and optimize the separation of varying size particles in a sheathless acoustic separation platform that was developed in our research lab. Specifically, the effect of flowrate, pressure amplitude, wavelength and interdigitated transducers (IDTs) physical parameters on the separation efficiency is explored. We also …

Development Of Polymer Composite Based Enabling Technologies For Lab-On-A-Chip Devices, Vinicio Carias

USF Tampa Graduate Theses and Dissertations

This dissertation presents enabling technologies to fabricate thermo-responsive polymer composite based Lab-on-a-Chip (LOC) devices. LOC devices, also known as micro-total-analytical systems (microTAS) or microfluidic devices can amalgamate miniaturized laboratory functions on a single chip. This significant size reduction decreases the amount of required fluid volumes down to nano or pico-liters. The main commercial application of LOC devices is the biomedical fields. However, these devices are anticipated to make a technological revolution similar to the way miniaturization changed computers. In fact, medical and chemical analyses are predicted to shift from room-sized laboratories to hand-held portable devices.

This dissertation is divided into …

Rtemis: Real-Time Tumoroid And Environment Monitoring Using Impedance Spectroscopy And Ph Sensing, Frank Alexander

USF Tampa Graduate Theses and Dissertations

This research utilizes Electrical Impedance Spectroscopy, a technique classically used for electrochemical analysis and material characterization, as the basis for a non-destructive, label-free assay platform for three dimensional (3D) cellular spheroids. In this work, a linear array of microelectrodes is optimized to rapidly respond to changes located within a 3D multicellular model. In addition, this technique is coupled with an on chip micro-pH sensor for monitoring the environment around the cells. Finally, the responses of both impedance and pH are correlated with physical changes within the cellular model. The impedance analysis system realized through this work provides a foundation for …

An Acoustic-Based Microfluidic Platform For Active Separation And Mixing, Myeong Chan Jo

USF Tampa Graduate Theses and Dissertations

Particle separation is of great interest to many biological and biomedical applications. Flow-based methods have been used to sort particles and cells. However, the main challenge with flow based particle separation systems is the need for a sheath flow for successful operation. Existence of the sheath liquid dilutes the analyte, necessitates precise flow control between sample and sheath flow, requires a complicated design to create sheath flow and separation efficiency depends on the sheath liquid composition. In addition, current gold standard active separation techniques are only capable of separation based on particle size; hence, separation cannot be achieved for same-size …

Zno Nanostructures: Growth, Characterization And Applications, Mikhail Ladanov

USF Tampa Graduate Theses and Dissertations

ZnO nanostructures have been investigated for quite a long time. However, only recently they triggered much interest due to advances in materials synthesis and characterization, as well as emerging demand for new nanostructured materials in novel device implementations.

A large part of the work was devoted to exploring new methodology for patterning growth sites and controlling nanowires morphology using the deposition methods that are compatible with integrated circuits (IC) processing. Microcontact printing was used to pattern the seeding layer, and, subsequently, ZnO nanowires through a resistless soft lithography process.

When considering hydrothermal growth of ZnO nanowires in the framework of …

Optimization Of Bio-Impedance Sensor For Enhanced Detection And Characterization Of Adherent Cells, Dorielle T. Price

USF Tampa Graduate Theses and Dissertations

This research focuses on the detection and characterization of cells using

impedance-based techniques to understand the behavior and response of cells to internal/environmental changes. In combination with impedimetric sensing techniques, the biosensors in this work allow rapid, label-free, quantitative measurements and are very sensitive to changes in environment and cell morphology. The biosensor design and measurement setup is optimized to detect and differentiate cancer cells and healthy (normal) cells. The outcome of this work will provide a foundation for enhanced 3-dimensional tumor analysis and characterization; thus creating an avenue for earlier cancer detection and reduced healthcare costs.

The magnitude of …