title: Thermo-responsive peptide-modified hydrogels for tissue regeneration.
abstract: Loosely cross-linked hydrogels consisting of N-isopropylacrylamide (NIPAAm) and acrylic acid (AAc) were synthesized, characterized, and used as model scaffolds for studying cell-material interactions in three-dimensions (3D). The AAc groups were functionalized with peptides containing the -RGD- and -FHRRIKA- sequences found in bone sialoprotein. Chemical modification of the hydrogels was verified via solid-state (1)H nuclear magnetic resonance spectroscopy, lower critical solution temperature studies, and volume change studies. The peptide-modified hydrogels were pliable at 22 degrees C and could be injected through a small-diameter aperture. Rat calvarial osteoblasts (RCO) seeded into the peptide-modified hydrogels were viable for at least 21 days of in vitro culture. The RCO spread more and demonstrated significantly greater proliferation when cultured within the peptide-modified hydrogels, as compared to control hydrogels. These peptide-modified P(NIPAAm-co-AAc) hydrogels serve as useful tools for studying cell-material interactions within 3D structures and have the potential to be used as injectable scaffolds for tissue engineering applications.
authors.affiliation: Department of Biomedical Engineering, Robert R. McCormick School of Engineering and Applied Sciences, Northwestern University, Evanston, Illinois 60208, USA.
authors.forename: R A
authors.initials: RA
authors.lastname: Stile
authors.forename: K E
authors.initials: KE
authors.lastname: Healy
mesh_terms: D000178:Acrylamides / Q000737:chemistry; D000179:Acrylates / Q000737:chemistry; D000595:Amino Acid Sequence; D000818:Animals; D001672:Biocompatible Materials / Q000138:chemical synthesis / Q000737:chemistry / Q000378:metabolism; D001861:Bone Regeneration; D002455:Cell Division; D002470:Cell Survival; D002478:Cells, Cultured; D020100:Hydrogels / Q000138:chemical synthesis* / Q000737:chemistry / Q000378:metabolism*; D009682:Magnetic Resonance Spectroscopy; D015394:Molecular Structure; D009842:Oligopeptides / Q000737:chemistry; D010006:Osteoblasts / Q000166:cytology; D010455:Peptides / Q000737:chemistry*; D051381:Rats; D012886:Skull / Q000166:cytology; D013696:Temperature; D023822:Tissue Engineering
chemical_list: D000178:Acrylamides; D000179:Acrylates; D001672:Biocompatible Materials; D020100:Hydrogels; D009842:Oligopeptides; D010455:Peptides; C047981:arginyl-glycyl-aspartic acid; C067295:N-isopropylacrylamide; C036658:acrylic acid