TY - JOUR TI - Biomaterials and microfabrication techniques for improved peripheral nerve regeneration DO - https://doi.org/doi:10.7282/T38W3DRH PY - 2007 AB - Following severe nerve injuries, surgery is required to physically reconnect the injured nerve for regeneration. Auto-grafting is typically considered to be the most effective method, but is problematic in terms of the limited supply of suitable nerves. Various artificial nerve materials are under investigation, but the lack of directional cues, biomolecular support, and the effects of inflammation at injury site limit the complete regeneration. Protein micropatterned surfaces generated by microcontact printing and micron scale plasma-initiated patterning allow the cellular environment to be manipulated by providing chemical and physical cues to neural cells. The first objective of this study is to modify these cues to control neural cell growth. Laminin, a common chemical cue, was modified by RGD conjugation to improve Schwann cell adhesion. This chemical cue modification resulted in improved Schwann cell adhesion and guidance. To change the physical cues, various micropattern dimensions ranging from 10 to 50 µm stripes with a consistent 40 µm space were prepared; neuron growth and guidance was optimal on the 40 µm striped pattern. The second objective was to generate a novel biomolecular gradient system using microfluidic techniques. Controlling the microfluidic channel dimensions, flow rate, and collagen gel properties created a three-dimensional, adhesive gradient within a collagen gel. The specific impact of the biomolecular gradient on neuron growth can be evaluated. The final objective was to utilize non-steroidal anti-inflammatory drug (NSAID) based - poly(anhydride-esters) (PAE) for nerve regeneration. These polymers are biodegradable and release NSAIDs upon hydrolytic degradation. The compatibility of four polymers with neurons and Schwann cells was evaluated; the salicylic acid-based PAE (SAA) proved the most biocompatible. The SAA nerve guidance conduit was fabricated and conduit properties characterized. Sufficient mechanical strength and biocompatibility of the conduit was demonstrated. This work demonstrates that nerve regeneration can be enhanced and improved by controlling neural cell guidance using micropatterned surfaces, fabricating a biomolecular gradient system using a microfluidic technique to investigate its impact on neuron growth, and applying drug-containing polymers as a nerve guidance conduit. KW - Biomedical Engineering KW - Nervous system KW - Regeneration (Biology) KW - Nerve grafting LA - English ER -