HONORABLE MENTION
Students: Samantha Mapps
Project: PEGylation of 3D-Printed Polycaprolactone Scaffolds
Major: Bioengineering
Advisor: Lesley Chow
Abstract
Osteoarthritis is a degenerative joint disease characterized by the progressive breakdown of cartilage. The highly organized nature of this tissue and its limited regenerative capacity makes it difficult to regenerate functional cartilage. To address this issue, 3D-printed biodegradable polymer scaffolds are often used to provide biochemical and mechanical support to stem cells and promote efficient healing of damaged tissue. Our lab solvent-cast 3D prints polycaprolactone (PCL)-based scaffolds with peptide-PCL conjugates to spatially control biochemical cues. We previously showed that multi-peptide organization significantly affects mesenchymal stromal cell (MSC) differentiation for osteochondral repair. However, scaffold stiffness also affects MSC response. To address this, we are modifying the scaffold surface with poly(ethylene glycol) (PEG) to create a softer substrate suitable for chondrogenesis towards cartilage without compromising the scaffold load-bearing capacity. We functionalized PCL-azide scaffolds with 8-arm PEG-DBCO to create a hydrated gel-like layer independent of bulk scaffold properties. This study aims to determine how using different solvents to dissolve PEG-DBCO affects PEG density on 3D-printed scaffold surfaces. Three different solutions (100% methanol, 50:50 ethanol/water, and 50:50 isopropanol/water) were selected based on variable PEG solubility. We hypothesize that minimizing PEG solubility will prevent chain swelling while the PEG is immobilized on the surface to maximize the amount of PEG tethered to the surface. We compared these solutions to control solutions (phosphate-buffered saline and water) by imaging the functionalized scaffolds with fluorescence microscopy.
About Samantha Mapps
Samantha Mapps (she/her) is a senior pursuing a B.S. in Bioengineering with a minor in Education at Lehigh University. She is an active member and leader in the Lehigh community, serving as President of the F1RST (First-Generation Student Initiative) Club, Mentor and Guide for the Lehigh University Student Scholars Institute (LUSSI), and an undergraduate researcher in the Chow Lab. Samantha has been conducting research with Dr. Lesley Chow alongside fellow undergraduate and graduate students for the past year. Her research primarily focuses on 3D printing scaffolds and investigating the effect of surface chemistry on cell behavior. She has also researched computational scaffold models using Solidworks and finite element analysis at the University of Galway under the guidance of Dr. Peter McHugh. Following graduation, Samantha hopes to pursue a career in the medical device industry to advance healthcare technology and improve patients' lives globally.