Faculty Mentor(s)
Dr. Meagan Elinski, Chemistry
Document Type
Poster
Event Date
4-12-2024
Abstract
Modern treatments for osteoarthritis increasingly involve the use of nanoparticles as drugdelivery systems, but there is little known about the influence of nanoparticle chemical composition and surface chemistry between nanoparticles and soft materials in sliding contact. This work implements cartilage-mimicking polyacrylamide (PAM) hydrogels as a well-studied, fundamental platform. In situ (in a fluid environment) macroscale friction tests as a function of shear rate were conducted with a rheometer with a tribology adapter, controlling for contact pressure. Comparing different nanoparticle compositions, citrate capped metal (gold) nanoparticles exhibited a 50% increase in friction relative to water. With no difference in solution viscosity, this difference is likely driven by hydrogen bonding between the citrate ligands and PAM surface. In contrast, carbon based nanoparticles (nanodiamonds) with no capping ligands exhibited a 50% decrease in friction relative to water. Here, a higher solution viscosity for the nanodiamonds is likely dictating the sliding mechanism. Additional tests exploring gold nanoparticles with controlled capping ligands further support the impact of intermolecular interactions between nanoparticle capping ligands and the PAM surface in controlling sliding mechanisms. Post-sliding characterization of the PAM with confocal Raman microscopy surfaces indicate no damage to the hydrogel, and the presence of uncapped nanoparticle aggregates. Next steps will focus on the extent to which nanoparticles might be embedded within the PAM surface as a result of sliding.
Recommended Citation
Repository citation: Buckley, Lauren; Bovia, Connor; and Gleeson, Griffin, "Role of Intermolecular Interactions between Nanoparticle Capping Ligands and Hydrogel Surfaces During Sliding" (2024). 23rd Annual A. Paul and Carol C. Schaap Celebration of Undergraduate Research and Creative Activity (2024). Paper 12.
https://digitalcommons.hope.edu/curca_23/12
April 12, 2024. Copyright © 2024 Hope College, Holland, Michigan.
Comments
This research was supported by the Hope College Chemistry Department Undergraduate Research Fund, Division of Natural & Applied Sciences, and prior awards with the Herbert H. and Grace A. Dow Foundation.