Access Type

Open Access Thesis

Date of Award

January 2024

Degree Type

Thesis

Degree Name

M.S.

Department

Biomedical Engineering

First Advisor

Harini G. Sundararaghavan

Abstract

Peripheral neuropathy is common and is a major source of pain that can lead to debilitating loss of function. Healing often requires medical intervention through autologous nerve grafts. However, autografting is not always successful and can lead to increased debilitation through donor site morbidity. Tissue engineering seeks to improve nerve injury treatment though the use of nerve conduits. Conduits made from functional biomaterials can be implanted into a nerve injury site encouraging and controlling axonal regrowth without causing additional harm to the patient. Both silk fibroin (SF) and hyaluronic acid (HA) have proven successful in the field of neural tissue engineering. SF has excellent mechanical properties and is attractive to cells. HA is familiar to cells and has proven successful in peripheral nerve regeneration. This study developed aligned combination SF-HA nanofibers through electrospinning that could be used within a nerve conduit. Both materials were also methacrylated to allow for photocrosslinking and additional control over material properties. SF-HA was tested alongside a material containing only HA that has already proven to be effective in literature. When characterizing the materials, it was found that through chemical methacrylation HA was substituted at 60% while SF reported a 30% substitution. Electrospun SF-HA nanofibers were found to have a greater diameter than HA fibers; however, SF-HA was found to be more aligned with greater surface hydrophobicity. Mechanically, it was found that both materials exceeded the properties of the native tissue, but SF-HA far exceeded HA in elasticity and overall fiber extension. Furthermore, human Schwann cells attached, proliferated, and released more pro-regenerative growth factors on SF-HA than HA. Dorsal root ganglia neurons also displayed a healthier cell morphology with longer neurite extensions on SF-HA fibers. Therefore, SF-HA nanofibers have potential as a nerve conduit material.

Share

COinS