Polymer Mimetics For Soil Modeling And Detection Of Biomarkers, Md Ragib Hasan

LSU Doctoral Dissertations

The population of the world is increasing day by day and is expected to reach 9.8 billion by the year 2050. The ever-increasing demand for agricultural products is putting an unprecedented strain on the world's soils as the human population continues to expand. Soil degradation caused by over-farming and the agrochemicals (fertilizers, pesticides, etc.) used in agriculture is a growing problem, although its causes remain murky. In addition, little is understood about the molecular-level interactions of substances that are subsequently introduced to soils, such as agricultural chemicals (ACs). Therefore, it is expected that these constraints may be circumvented by the …

Leveraging Isocyanate Chemistry For Low Cost And Highly Functional Hydrogels, Henry Beaman

Dissertations - ALL

The development of novel biomaterials is an important step in providing higher quality products for wound healing, drug delivery, and tissue engineering. Progress is consistently being made in the development of new polymers, yet new polymer systems are often expensive and/or involve complex multistep synthesis methods. These limitations could hinder the translation and scalability of functionalized materials. To address the issues of complex synthesis and high cost, we have devised strategies for polymeric modification using isocyanate chemistry. Isocyanates are used in the manufacturing of polyurethanes. Isocyanates are highly reactive with common functional groups, such as amines, hydroxyls, and carboxylic acids. …

Characterization Of Thermal Gelation Properties In Bioresorbable Thermally Activated Hydrogel Polymers For Hernia Surgery Applications, Alexander Mayfield

All Theses

Hydrogel adhesives are a new class of materials with excellent biocompatibility, which makes them very attractive for biomaterial applications. It has been previously shown that Tetronic T1107, a four-arm poly (propylene oxide)-poly (ethylene oxide) (PPO-PEO) block copolymer, is useful as a chemical crosslinking thermo-responsive hydrogel for bioadhesive applications. The end groups of this polymer are modified with acrylate and N-hydroxysuccinimide (NHS) functional groups. The acrylate end group gives the polymer cohesive properties with long-range chemical crosslinking using dithiothreitol (DTT), while the NHS end group gives the polymer adhesive properties through bonding with amines found in organic tissue. It was found …

A Bioaffinity Self-Assembling Gel For Localized Delivery Of Immunotherapeutics, Ngoc Pham

Electronic Theses and Dissertations

Renal cell carcinoma (RCC) is a type of cancer in which malignant cells develop in the kidney tubules. Immune checkpoint inhibitors (ICI), including anti-PD-1 antibodies (aPD1), as monotherapies or in combination settings have advanced to the front-line treatment for patients diagnosed with RCC. Systemic infusion of ICI may render subtherapeutic concentrations in the lesions and increase risks of immune-related adverse events. To overcome these limitations, locoregional drug delivery has gained substantial interests as a modality in immuno-oncology. However, conventional intratumoral injections may be ineffective because the high interstitial fluid pressure in tumors resists drug retention and results in rapid local …

The Effects Of A Carbohydrate Hydrogel Beverage On Gastrointestinal Symptoms And Running Performance In Comparison To Conventional Carbohydrate Beverages, Nicholas Minichiello

Masters Theses, 2020-current

PURPOSE: The utilization of hydrogel technology allows carbohydrate beverages to form a gel in the acidic environment of the stomach, potentially enhancing gastric emptying. However, few studies have researched the effects of these beverages on gastrointestinal (GI) tolerance and exercise performance; there is minimal data in a variety of exercise conditions and/or beverage ingestion rates. The purpose of the present study was to assess the effects of a 80 g/h of maltodextrin-fructose hydrogel (MF-H) beverage versus conventional carbohydrate sources on GI symptoms and running performance. METHODS: eight distance runners (26 ± 5 y; VO_2max = 65 ± 7 ml/kg/min) …

Developing Hydrogel-Based X-Ray Visualized Implantable Sensors To Non-Invasively Measure Ph For Tracking Tumor Response And Detecting Peritoneal Infections, Kiridena Mudiyanselage Sachindra Dulashini Kiridena

All Dissertations

The goal of my dissertation research is to develop injectable and implantable biosensors to measure tumor pH to study cancer pathophysiology and effectiveness of treatments and peritoneal infections using plain radiography. The pH in cancer tissues plays an important role in determining cancer progression and treatment. Local acidosis is believed to be an indicator of dormant regions that are more resistant to therapies, a contributor to metastasis, and influence immune responses. We are designing a hydrogel-based sensor that can be injected into tumors during needle biopsy procedures and/or procedures to add markers for image-guided therapies. The pH response of the …

Developing Implantable Hydrogel-Based Sensors To Measure Biomarkers In Synovial Joint Fluid Using Plain Radiography, Uthpala N. Wijayaratna

All Dissertations

The goal of my dissertation research is to develop implantable sensors that attach to prosthesis prior to implantation and measures biomarkers of infection in joint fluid in order to detect, monitor, and study infection using plain radiography. Joint replacement surgeries are common procedures improving the mobility and lives of millions of people worldwide. Although the surgeries are generally successful, about 1% of prosthetic hips become infected. If the infections are not detected and treated promptly with antibiotics and surgical debridement, device removal is almost always required to treat the infections. Therefore, it’s important to detect post-surgery infections early and monitor …

Synthesis Of Thiol-Acrylate Hydrogels For 3d Cell Culture And Microfluidic Applications, Anowar Hossain Khan

LSU Doctoral Dissertations

Globally cell culture is an $18.98 billion industry as of 2020, with an 11.6 percent annual growth rate. Drug discovery has an estimated worth of $69.8 billion in 2020 and is predicted to grow to $110.4 billion by 2025. Three-dimensional (3D) cell culture of cancer cells is one of the rapidly growing felids since it better recapitulates in vivo conditions compared to two-dimensional (2D) models. However, it is challenging to grow 3D tumor spheroids outside the body, and some of the existing technology can generate these spheroids outside the human body but poorly mimic in vivo tumor models. Therefore, there …

Optimization Of A Novel Nipam-Based Thermoresponsive Copolymer For Intramuscular Injection As A Myoblast Delivery Vehicle To Combat Peripheral Artery Occlusive Disease, Quentin R. Klueter

Master's Theses

There is a need for a minimally invasive delivery method to enable cell therapies to combat peripheral artery occlusive disease (PAOD) in end stage patients. Myoblasts show promise as a cell mediated therapy but warrant an improved delivery method to increase cell retention in the region of interest because of their adherent nature, relative to previously used BM-MNC’s that are non-adherent. Contemporary issues with achieving successful cell therapies of vasculature can be mainly characterized by the lack of clinical translation from promising animal studies and absence of cell delivery scaffolding. Naturally, polymers have been widely experimented with as grafts to …

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 …

Development Of Cellulose-Based, Semi-Interpenetrating Network Hydrogels As Tissue-Adhesive, Thermoresponsive, Injectable Implants, Jesse Martin

Dissertations and Theses

Abstract Development of Cellulose-Based, Semi-Interpenetrating Network Hydrogels as Tissue-Adhesive, Thermoresponsive, Injectable Implants

Hydrogels are three-dimensional polymer networks with high water content and tunable mechanical properties, which have been widely investigated as replacements for soft tissues, such as the intervertebral disc (IVD). Various derivatives of the plant polysaccharide, cellulose, have been explored for use as injectable hydrogel implants. Methylcellulose (MC), which exhibits thermogelation at temperatures above 32°C, and relatively hydrophilic carboxymethyl-cellulose (CMC), are versatile cellulosic polymers that have shown promise as base materials for such applications. In prior work, functionalization with methacrylate groups allowed for the formation of stable, covalently crosslinked …

Mesenchymal Stromal Cell And Chondrocyte Mobility In 3d Bioprinted Hydrogel Constructs, Alesia Lokshina

Honors Undergraduate Theses

Osteoarthritis (OA) is a progressive cartilage degeneration disease with a complex pathologic mechanism. Although OA has devastating effects on patient quality of life and places a significant burden on the healthcare system, no disease-modifying drugs have been found, and surgical treatment options are often unsustainable. 3D bioprinting is a novel field within tissue engineering that focuses on developing biocompatible constructs that can be implanted to replace an organ or tissue. Such constructs have a great potential to become treatments for OA. Understanding cell mobility within hydrogels could play a vital role in advancing the development of biocompatible constructs. However, due …