Engineering a multifunctional scaffold for spinal cord repair

Abstract

The goal of this project is to create an nondegradable scaffold that would serve as a mechanical stabilization, a drug delivery device and a protected environment for the regeneration of neurons and blood vessels post spinal cord injury. The proposed scaffold would be made from a copolymer of HEMA and PEG. Degradable microparticles loaded with therapeutic proteins to promote regeneration of neurons and blood vessels would be incorporated into the scaffold. The microparticles allow a controlled, sustainable release of these proteins. Preliminary work has shown that the protein-loaded microparticles have been successfully entrapped into the hydrogel matrix and tailoring of the mechanical properties can be achieved by varying the water content during polymerization. Gels ranging from 70-75% water match the compressive modulus of the spinal cord gray matter when made via redox imitated free radical polymerization. Addition of microparticles to the polymerization mixture creates an edge effect making the mechanical properties of the gel drastically different. The ability of the scaffold synthesis to adapt to match the mechanical properties of the gray matter is crucial in its realizability as an implant. Other factors being investigated are the bio compatibility of the polymers and the release profiles of the therapeutic proteins.