title: Biodegradable elastomeric scaffolds with basic fibroblast growth factor release.
abstract: Scaffolds that better approximate the mechanical properties of cardiovascular and other soft tissues might provide a more appropriate mechanical environment for tissue development or healing in vivo. An ability to induce local angiogenesis by controlled release of an angiogenic factor, such as basic fibroblast growth factor (bFGF), from a biodegradable scaffold with mechanical properties more closely approximating soft tissue could find application in a variety of settings. Toward this end biodegradable poly(ester urethane)urea (PEUU) scaffolds loaded with bFGF were fabricated by thermally induced phase separation. Scaffold morphology, mechanical properties, release kinetics, hydrolytic degradation and bioactivity of the released bFGF were assessed. The scaffolds had inter-connected pores with porosities of 90% or greater and pore sizes ranging from 34-173 microm. Scaffolds had tensile strengths of 0.25-2.8 MPa and elongations at break of 81-443%. Incorporation of heparin into the scaffold increased the initial burst release of bFGF, while the initial bFGF loading content did not change release kinetics significantly. The released bFGF remained bioactive over 21 days as assessed by smooth muscle mitogenicity. Scaffolds loaded with bFGF showed slightly higher degradation rates than unloaded control scaffolds. Smooth muscle cells seeded into the scaffolds with bFGF showed higher cell densities than for control scaffolds after 7 days of culture. The bFGF-releasing PEUU scaffolds thus exhibited a combination of mechanical properties and bioactivity that might be attractive for use in cardiovascular and other soft tissue applications.
authors.affiliation: McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania 15219, USA.
authors.forename: Jianjun
authors.initials: J
authors.lastname: Guan
authors.forename: John J
authors.initials: JJ
authors.lastname: Stankus
authors.forename: William R
authors.initials: WR
authors.lastname: Wagner
mesh_terms: D043925:Angiogenesis Inducing Agents / Q000737:chemistry* / Q000494:pharmacology; D000818:Animals; D001672:Biocompatible Materials; D049109:Cell Proliferation / Q000187:drug effects; D002478:Cells, Cultured; D002626:Chemistry, Pharmaceutical; D003692:Delayed-Action Preparations; D004337:Drug Carriers; D004339:Drug Compounding; D004355:Drug Stability; D020724:Elastomers / Q000138:chemical synthesis / Q000737:chemistry*; D005079:Excipients / Q000737:chemistry; D016222:Fibroblast Growth Factor 2 / Q000737:chemistry* / Q000494:pharmacology; D006493:Heparin / Q000737:chemistry; D006868:Hydrolysis; D007700:Kinetics; D032389:Myocytes, Smooth Muscle / Q000187:drug effects; D011091:Polyesters / Q000138:chemical synthesis / Q000737:chemistry*; D016062:Porosity; D051381:Rats; D012710:Serum Albumin, Bovine / Q000737:chemistry; D012995:Solubility; D013499:Surface Properties; D013678:Technology, Pharmaceutical / Q000379:methods; D013718:Tensile Strength; D023822:Tissue Engineering / Q000379:methods
chemical_list: D043925:Angiogenesis Inducing Agents; D001672:Biocompatible Materials; D003692:Delayed-Action Preparations; D004337:Drug Carriers; D020724:Elastomers; D005079:Excipients; D011091:Polyesters; C497893:poly(ester urethane)urea; D016222:Fibroblast Growth Factor 2; D012710:Serum Albumin, Bovine; D006493:Heparin