Project Title: Development of Novel Agarose and Methylcellulose Hydrogel Blends for Nerve Regeneration  Applications

Department: Biomedical Engineering
Faculty Advisor: Dr. Ryan Gilbert, Biomedical Engineering
Student Researchers  Benton Martin, Sherri Wiseman, Rebecca Klank
Abstract
Trauma sustained to the central nervous system is a debilitating problem for thousands of people worldwide. Neuronal regeneration within central nervous system is hindered by several factors. Injury stimulates astrocytes to produce inhibitory extracellular matrix molecules which impede regeneration. Inhibitors within myelin, an irregular geometry, and the lack of scaffolding are other factors that constrain neuronal regeneration. Biocompatible hydrogels, injectable at room temperature, that rapidly gel at physiological temperatures (37˚C) are beneficial materials that could hold potential scaffolding materials within the injury site and slowly release beneficial therapeutics to improve regeneration outcomes. Our studies have shown that thermoreversible methylcellulose hydrogels can be combined with nerve growth supportive agarose to create hydrogel blends that accommodate these properties. Three separate novel hydrogel blends were created each using one of three different commercially available agaroses mixed with methylcellulose. Gelation time tests show that the blends gel at a faster rate than base methylcellulose at 37˚C, and culturing experiments show biocompatibility with dissociated dorsal root ganglia neurons. The different blends were further assessed using degradation tests, evaluating pore size characteristics using scanning electron microscopy, and injectability tests. This research demonstrates that blends of agarose and methylcellulose solidify much more quickly than plain methylcellulose, while solidifying at physiological temperatures that agarose cannot solidify at. Thus, these hydrogel blends merit further consideration as a component of a multi-faceted approach to promote nerve regeneration within the damaged spinal cord.