Engineering Commons^™

Optofluidic Spectroscopy Platform For Detection Of Hemolysis, Edikan Archibong

USF Tampa Graduate Theses and Dissertations

In the United States alone, hundreds of millions of blood tests are performed annually, and a significant number of those tests are compromised due to hemolysis: e.g., 31% compromised in emergency rooms (inpatient) and 10% at blood banks, clinics, and other outpatient venues. Currently there is no way to reliably detect hemolysis without plasma separation. As a result, significant delays ensue, potentially negatively affecting patient diagnosis and treatment. In addition to in vitro hemolysis, which compromises the quality of blood tests, hemolysis can also occur in vivo. The in vivo occurrence of hemolysis is an indication of life-threatening complications. …

Smartphone Based 3d Printed Colorimeter For Biomedical Applications, Karthik Raj Konnaiyan

USF Tampa Graduate Theses and Dissertations

Here we present a novel Smartphone-based colorimeter and demonstrate its application to the measurements of glucose and protein concentrations in biological samples. The key innovation of our approach was to combine powerful image processing encoded into a mobile phone application with a low cost 3D printed sample holder that allowed to control lighting conditions and significantly improved sensitivity. Different solutions with protein and glucose concentrations ranging from 0 to 2000 mg/dL were prepared and analyzed using our system. The Smartphone-based colorimeter always correctly classified the corresponding reagent strip pads, what confirms that it can be used as a low cost …

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 …

Assessing Viscoelastic Properties Of Polydimethylsiloxane (Pdms) Using Loading And Unloading Of The Macroscopic Compression Test, Mustafa Fincan

USF Tampa Graduate Theses and Dissertations

Polydimethylsiloxane (PDMS) mechanical properties were measured using custom-built compression test device. PDMS elastic modulus can be varied with the elastomer base to the curing agent ratio, i.e. by changing the cross-linking density. PDMS samples with different crosslink density in terms of their elastic modulus were measured. In this project the PDMS samples with the base/curing agent ratio ranging from 5:1 to 20:1 were tested. The elastic modulus varied with the amount of the crosslinker, and ranged from 0.8 MPa to 4.44 MPa. The compression device was modified by adding digital displacement gauges to measure the lateral strain of the sample, …

Fabrication Of Tissue Precursors Induced By Shape-Changing Hydrogels, Olukemi O. Akintewe

USF Tampa Graduate Theses and Dissertations

Scaffold based tissue reconstruction inherently limits regenerative capacity due to inflammatory response and limited cell migration. In contrast, scaffold-free methods promise formation of functional tissues with both reduced adverse host reactions and enhanced integration. Cell-sheet engineering is a well-known bottom-up tissue engineering approach that allows the release of intact cell sheet from a temperature responsive polymer such as poly-N-isopropylacrylamide (pNIPAAm). pNIPAAm is an ideal template for culturing cell sheets because it undergoes a sharp volume-phase transition owing to the hydrophilic and hydrophobic interaction around its lower critical solution temperature (LCST) of 32°C, a temperature close to physiological temperature. Compared to …

Understanding The Role Of Colloidal Particles In Electroporation Mediated Delivery, Alisha Peterson

USF Tampa Graduate Theses and Dissertations

Electroporation (EP) is a physical non-viral technique used to deliver therapeutic molecules across the cell membrane. During electroporation an external electric field is applied across a cell membrane and it causes pores to form. These pores then allow the surrounding media containing the therapeutics to diffuse across the membrane. This technique has been specifically studied as a promising gene and drug delivery system. Colloidal particles have also proven to be promising for a variety of biological applications including molecular delivery, imaging, and tumor ablation, due to their large surface area and tunable properties. In more recent years researchers have explored …

Impedance Measurements As A Means To Improve The Biological Response Of Gene Electrotransfer, Lina Fajardo Gomez

USF Tampa Graduate Theses and Dissertations

When an electric field is locally applied to tissues in vivo the uptake of exogenous DNA can be greatly increased. This approach to gene transfer, called electroporation (EP) or gene electro transfer (GET), has potential applications in the treatment of skin disorders, vaccinations, some types of cancer and metabolic diseases. The eect of electric elds on cells and tissues has been studied and related to the uptake of DNA. Tissue impedance changes have been measured as a result of electroporation. The aim of this study is to explore the predictive accuracy of impedance spectroscopy for the success of GET. Mice …

Silicone Elastomer-Based Combinatorial Biomaterial Gradients For High Throughput Screening Of Cell-Substrate Interactions, Greeshma Mohan

USF Tampa Graduate Theses and Dissertations

Biomaterials have evolved over the years from the passive role of mere biocompatibility to an increasingly active role of presenting instructive cues to elicit precise responses at the molecular and cellular levels. Various characteristics common to synthetic biomaterials in vitro and extracellular matrices in vivo, such as immobilized functional or peptide groups, mechanical stiffness, bulk physical properties and topographical features, are key players that regulate cell response. The dynamics in the cell microenvironment and at the cell adhesive interface trigger a web of cell-material and cell-cell information exchanges that have a profound impact in directing the ultimate cell fate …