Therapeutic Injectable Iron-Chelating Hydrogels, Debbie Campbell-Rance

Theses and Dissertations

ABSTRACT

Therapeutic Injectable Iron-Chelating Hydrogels for Improved Central Nervous System Regeneration

By

Debbie S. Campbell-Rance

A dissertation submitted in partial fulfillment of the requirements of the degree of Doctor of Philosophy at Virginia Commonwealth University 2021.

Director: Xuejun Wen, M.D., Ph.D., AIMBE Fellow, Alice T. and William H. Goodwin Jr. Endowed Chair Professor in Regenerative Medicine, Institute for Engineering and Medicine, Department of Chemical and Life Science Engineering

Severe traumatic brain and spinal cord injuries are major global public health and socioeconomic problems in terms of mortality and morbidity. Currently there are two main lines of treatment under development for …

An Injectable Stem Cell Delivery System For Treatment Of Musculoskeletal Defects, Shirae Leslie

Theses and Dissertations

The goal of this research was to develop a system of injectable hydrogels to deliver stem cells to musculoskeletal defects, thereby allowing cells to remain at the treatment site and secrete soluble factors that will facilitate tissue regeneration. First, production parameters for encapsulating cells in microbeads were determined. This involved investigating the effects of osmolytes on alginate microbead properties, and the effects of alginate microbead cell density, alginate microbead density, and effects of osteogenic media on microencapsulated cells. Although cells remained viable in the microbeads, alginate does not readily degrade in vivo for six months. Therefore, a method to incorporate …

Design, Fabrication And Performance Evaluation Of An Impedimetric Urea Biosensor System, Vandana Gupta

Theses and Dissertations

An impedance bioanalyzer system comprising an in-vitro biotransducer, instrumentation and control software for the measurement of urea, potentially in blood dialysate, has been developed. The biotransducer comprises of a microlithographically fabricated interdigitated microsensor electrode (IME) onto which was cast a biorecognition layer conferred with the specificity of the enzyme urease. Urease hydrolysis of urea produces NH4+, HC03- and OH- ions that decrease the device's impedance. The temporal rate of change (kinetic) and the extent of change (equilibrium) of ion concentration were measured as the sensor's response. Five formats: [i) unPEGylated urease-containing poly(hydroxyethylmethacrylate) [p(HEMA)] hydrogel, ii) PEGylated urease-containing p(HEMA) hydrogel, iii) …