title: Structure-property evaluation of thermally and chemically gelling injectable hydrogels for tissue engineering.
abstract: The impact of synthesis and solution formulation parameters on the swelling and mechanical properties of a novel class of thermally and chemically gelling hydrogels combining poly(N-isopropylacrylamide)-based thermogelling macromers containing pendant epoxy rings with polyamidoamine-based hydrophilic and degradable diamine cross-linking macromers was evaluated. Through variation of network hydrophilicity and capacity for chain rearrangement, the often problematic tendency of thermogelling hydrogels to undergo significant syneresis was addressed. The demonstrated ability to tune postformation dimensional stability easily at both the synthesis and formulation stages represents a significant novel contribution toward efforts to utilize poly(N-isopropylacrylamide)-based polymers as injectable biomaterials. Furthermore, the cytocompatibility of the hydrogel system under relevant conditions was established while demonstrating time- and dose-dependent cytotoxicity at high solution osmolality. Such injectable in situ forming degradable hydrogels with tunable water content are promising candidates for many tissue-engineering applications, particularly for cell delivery to promote rapid tissue regeneration in non-load-bearing defects.
authors.affiliation: Department of Bioengineering, Rice University, Houston, Texas 77030, USA.
authors.forename: Adam K
authors.initials: AK
authors.lastname: Ekenseair
authors.forename: Kristel W M
authors.initials: KW
authors.lastname: Boere
authors.forename: Stephanie N
authors.initials: SN
authors.lastname: Tzouanas
authors.forename: Tiffany N
authors.initials: TN
authors.lastname: Vo
authors.forename: F Kurtis
authors.initials: FK
authors.lastname: Kasper
authors.forename: Antonios G
authors.initials: AG
authors.lastname: Mikos
mesh_terms: D000178:Acrylamides / Q000737:chemistry*; D000180:Acrylic Resins; D000818:Animals; D001672:Biocompatible Materials / Q000138:chemical synthesis* / Q000494:pharmacology; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects; D003432:Cross-Linking Reagents / Q000737:chemistry; D050091:Dendrimers / Q000737:chemistry*; D005347:Fibroblasts / Q000166:cytology / Q000187:drug effects; D020100:Hydrogels; D057927:Hydrophobic and Hydrophilic Interactions; D007267:Injections; D009682:Magnetic Resonance Spectroscopy; D008422:Materials Testing; D009994:Osmolar Concentration; D011108:Polymers / Q000737:chemistry*; D051381:Rats; D012212:Rheology; D013696:Temperature; D023822:Tissue Engineering / Q000379:methods*; D054457:Tissue Scaffolds; D014867:Water
chemical_list: D000178:Acrylamides; D000180:Acrylic Resins; D001672:Biocompatible Materials; D003432:Cross-Linking Reagents; D050091:Dendrimers; D020100:Hydrogels; C104700:PAMAM Starburst; D011108:Polymers; D014867:Water; C052970:poly-N-isopropylacrylamide