title: Conjugate addition reactions combined with free-radical cross-linking for the design of materials for tissue engineering.
abstract: PEG-diacrylamide was synthesized and utilized to make materials for tissue engineering. Acrylamide groups readily react with thiol groups, and peptides containing a single thiol group were coupled to the PEG-diacrylamide in aqueous solution at room temperature in about 2 h. If only a portion of the acrylamide groups were targeted for reaction with peptide, sufficient amounts of PEG-diacrylamide remained to be polymerized by free-radical mechanisms via photoinitiation. The photopolymerization step can be performed in contact with cells, providing a means to produce bioactive scaffolds for tissue engineering. The photopolymerization conditions and precursor composition greatly affect the stiffness of the materials, which subsequently affected cell spreading. The kinetics and extent of cell spreading on the bioactive materials were measured and compared to cell spreading on tissue culture polystyrene. Although the PEG materials resist protein adsorption, the experiments suggest that the cells can secrete extracellular matrix that can adhere to the gels.
authors.affiliation: Department of Materials and Institute for Biomedical Engineering, ETH-Zurich and University of Zurich, Moussonstrasse 18, CH-8044 Zurich, Switzerland.
authors.forename: D L
authors.initials: DL
authors.lastname: Elbert
authors.forename: J A
authors.initials: JA
authors.lastname: Hubbell
mesh_terms: D000178:Acrylamides / Q000737:chemistry*; D002448:Cell Adhesion; D003432:Cross-Linking Reagents / Q000737:chemistry*; D004847:Epithelial Cells / Q000166:cytology; D005347:Fibroblasts / Q000166:cytology; D006801:Humans; D010455:Peptides / Q000737:chemistry*; D011092:Polyethylene Glycols / Q000737:chemistry*; D023822:Tissue Engineering
chemical_list: D000178:Acrylamides; D003432:Cross-Linking Reagents; D010455:Peptides; D011092:Polyethylene Glycols