Characterizing the degradation of alginate hydrogel for use in multilumen scaffolds for spinal cord repair.
Alginate was studied as a degradable nerve guidance scaffold material in vitro and in vivo. In vitro degradation rates were determined using rheology to measure the change in shear modulus vs time. The shear modulus decreased from 155 kPa to 5 kPa within 2 days; however, alginate samples maintained their superficial geometry for over 28 days. The degradation behavior was supported by materials characterization data showing alginate consisted of high internal surface area (400 m2/g), which likely facilitated the release of cross-linking cations resulting in the rapid decrease in shear modulus. To assess the degradation rate in vivo, multilumen scaffolds were fabricated using a fiber templating technique. The scaffolds were implanted in a 2-mm-long T3 full transection rodent spinal cord lesion model for 14 days. Although there was some evidence of axon guidance, in general, alginate scaffolds degraded before axons could grow over the 2-mm-long lesion. Enabling alginate-based scaffolds for nerve repair will likely require approaches to slow its degradation. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 611-619, 2016.
Department of Macromolecular Science and Engineering, University of Michigan, Ann Arbor, Michigan, 48109.
Dena
D
Shahriari
Department of Neuroscience, University of California San Diego, La Jolla, California, 92093.
Jacob
J
Koffler
Department of Chemical Engineering and Materials Science, Michigan State University, East Lansing, Michigan, 48824.
Daniel A
DA
Lynam
Department of Neuroscience, University of California San Diego, La Jolla, California, 92093.|Veterans Administration Medical Center, San Diego, California, 92161.
Mark H
MH
Tuszynski
Department of Mechanical Engineering, University of Michigan, Ann Arbor, Michigan, 48109.
Jeffrey S
JS
Sakamoto
D000464:Alginates / Q000737:chemistry*; D000818:Animals; D005260:Female; D020723:Glucuronic Acid / Q000737:chemistry; D048091:Guided Tissue Regeneration / Q000379:methods*; D006603:Hexuronic Acids / Q000737:chemistry; D020136:Hydrogel, Polyethylene Glycol Dimethacrylate / Q000737:chemistry*; D007382:Intermediate Filaments / Q000378:metabolism; D009584:Nitrogen / Q000737:chemistry; D019904:Polymethyl Methacrylate / Q000737:chemistry; D016062:Porosity; D011916:Rats, Inbred F344; D012212:Rheology; D013116:Spinal Cord / Q000473:pathology; D013119:Spinal Cord Injuries / Q000628:therapy*; D054457:Tissue Scaffolds / Q000737:chemistry*
D000464:Alginates; D006603:Hexuronic Acids; D020136:Hydrogel, Polyethylene Glycol Dimethacrylate; D020723:Glucuronic Acid; D019904:Polymethyl Methacrylate; D009584:Nitrogen
alginate; degradation; hydrogel; nerve regeneration; rheology; spinal cord injury