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Thermo-responsive peptide-modified hydrogels for tissue regeneration.

R A Stile·K E Healy
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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.

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AcrylamidesAcrylatesAmino Acid SequenceAnimalsBiocompatible MaterialsBone RegenerationCell DivisionCell SurvivalCells, CulturedHydrogelsMagnetic Resonance SpectroscopyMolecular StructureOligopeptidesOsteoblastsPeptidesRatsSkullTemperatureTissue EngineeringJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, P.H.S.

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R A Stile, K E Healy. 2001. Thermo-responsive peptide-modified hydrogels for tissue regeneration.. https://doi.org/10.1021/bm0000945

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