Discipline: Convergence Science
Subcategory: Biomedical Engineering
Session: 3
Room: Exhibit Hall
Danielle Murray - University of Connecticut
Osteoarthritis is a very common degenerative joint disease that occurs when cartilage gradually wears away, leaving behind a frayed, rough surface. Over time, this thinned cartilage can cause the bones to rub together, making smooth joint movement more difficult. Pain and disability is a more common symptom especially at more advanced stages when cartilage has completely worn away and bone structural changes are obvious. Although Osteoarthritis can’t be reversed, there are common treatments that can help reduce pain symptoms. Although noninvasive, inexpensive, or short-relief, treatment options for Osteoarthritis currently remain limited, there have been more and more studies into the applications of biomaterials for the treatment of pain. We have available procedures like viscosupplementation, scaffolding, artificial joints, etc., that all use various methods of biomaterials to treat and diagnose Osteoarthritis pain. However, the impact of repeat injections has not yet been thoroughly researched. Nanotechnology, such as microspheres, are still being studied as drug delivery systems for localised and controlled drug administration over extended periods of time. In this study, we wanted to explore if we could improve a hydrogel biomaterial system for the sustained and controlled delivery of analgesic molecules, by modifying the degree of acetylation in conjunction with the concentration of lysozyme present.Enzymatic cross-linking processes were used to prepare the injectable biodegradable hydrogels from 3-(4-Hydroxyphenyl)-propionic acid and Glycol Chitosan with various degrees of acetylation. After determining that lysozyme dispersed in the media didn’t allow for a hydrogel to form, lysozyme was dispersed in the hydrogel and Horseradish Protein (HRP) was added to the complex to support stability. The 0.5 HPP-GC with incorporated HRP and Lysozyme degraded slower, by about half the amount of time, than 1.0 HPP-GC of the same formula in several trials. An additional BCA Protein Assay was performed to measure the protein concentrations for the 0.5 and 1.0 degrees of acetylation of the HPP-GC, HRP & lysozyme-mediated hydrogel complexes at 562 nanometers. The standard curve analysis indicated less lysozyme present inside the hydrogel complex after completion of degradation study. These results indicated that lysozyme-mediated degradation is dependent on the degree of acetylation.Qualitative assessment results concluded that the degradation of the hydrogel is dependent on the degree of acetylation of the polymer, with higher degrees of acetylation showing faster degradation periods. Quantitive assessment results saw that less lysozyme incorporation occurred within the hydrogel with higher degrees of separation. Further research involves testing more degrees of acetylation and lower range ratios of polymer to lysozyme to further manipulate time span and efficacy. Additionally, injecting the hydrogel to study suspended drug release interactions within the hydrogel and lysozyme complex.
Funder Acknowledgement(s): I would like to thank Dr. Cato Laurencin and Dr. Lakshmi S. Nair for their mentorship and support throughout the study, and for welcoming me into the team. Dr. Kevin Wai Hong Lo for his logistical support. I would also like to extend my thanks to Dr. Brittany Knight, Erick Orozco Morato, David Onwuka, and Devika Kishnan for their supplemental guidance and knowledge.
Faculty Advisor: Lakshmi Nair, nair@uchc.edu
Role: I researched the history of the pain model, Osteoarthritis, that was used for this study and reviewed the article “Degradation-Dependent Protein Release from Enzyme Sensitive Injectable Glycol Chitosan Hydrogel” that this project was based on. I prepared and acetylated the HPP-GC polymer, and formed the HPP-GC/lysozyme hydrogel complexes. After monitoring and analysing the rate of degradation, I further analysed the results using a BCA Assay kit for protein quantification. I engaged in background review of similar studies done in the past and created a set of future directions for a more in depth study. I noted troubleshooting efforts and limitations faced in order to use as a basis for future study.