title: Investigation of microstructure, mechanical properties and cellular viability of poly(L-lactic acid) tissue engineering scaffolds prepared by different thermally induced phase separation protocols.
abstract: Two thermally induced phase separation (TIPS) methods have been used to fabricate biodegradable poly(L-lactic acid) (PLLA) tissue engineering scaffolds each with fibrous (F-TIPS) and porous (P-TIPS) microstructures. Three levels of PLLA concentration (3, 5 and 7 wt%) were employed in each fabrication method and both wet and dry specimens were studied. Simple compression testing revealed that an elastic-plastic representation of the mechanical behavior was possible for all specimens. Both elastic and plastic moduli were higher for the P-TIPS, for higher polymer concentration, and might be somewhat higher for dry as opposed to wet specimens. For F-TIPS specimens, permanent deformation occurred successively during cyclic deformation but a "memory effect" simplified the behavior. Although F-TIPS microstructure better resembled the natural extracellular matrix, human osteosarcoma fibroblast cells showed more consistent viability in the P-TIPS scaffolds under our unloaded test protocols. Biodegradation in cell culture medium resulted in a decreased elastic moduli for F-TIPS specimens. Information presented regarding the microstructure, mechanical properties and cell viability of these PLLA scaffolds that should help reduce the number of iterations involved in developing tissue engineering products.
authors.affiliation: Department of Mechanical and Mechatronics Engineering, University of Waterloo, 200 University Avenue West, Waterloo, ON, Canada N2L 3G1. s2mollad@uwaterloo.ca
authors.forename: Sara
authors.initials: S
authors.lastname: Molladavoodi
authors.forename: Maud
authors.initials: M
authors.lastname: Gorbet
authors.forename: John
authors.initials: J
authors.lastname: Medley
authors.forename: Hyock Ju
authors.initials: HJ
authors.lastname: Kwon
mesh_terms: D000293:Adolescent; D001672:Biocompatible Materials / Q000737:chemistry* / Q000494:pharmacology*; D045744:Cell Line, Tumor; D002470:Cell Survival / Q000187:drug effects; D019245:Compressive Strength; D006801:Humans; D019344:Lactic Acid / Q000737:chemistry*; D008297:Male; D008422:Materials Testing; D055595:Mechanical Phenomena; D011091:Polyesters; D011108:Polymers / Q000737:chemistry*; D013696:Temperature; D023822:Tissue Engineering / Q000379:methods*; D054457:Tissue Scaffolds / Q000737:chemistry*
chemical_list: D001672:Biocompatible Materials; D011091:Polyesters; D011108:Polymers; D019344:Lactic Acid; C033616:poly(lactide)