Photocrosslinked Biodegradable Fibrous Scaffolds with Tunable Properties for Tissue Engineering Applications

摘要

It is becoming increasingly apparent that the architecture and mechanical properties of scaffolds, particularly with respect to mimicking features of natural tissues, are important for tissue engineering applications. Acrylated poly(glycerol sebacate) (Acr-PGS) is a material that can be crosslinked upon exposure to ultraviolet light, leading to networks with tunable mechanical and degradation properties through simple changes during Acr-PGS synthesis. For example, the number of acrylate functional groups on the macromer dictates the concentration of crosslinks formed in the resulting network. Three macromers were synthesized that form networks that vary dramatically with respect to their tensile modulus (~30 kPa to 6.6 MPa) and degradation behavior (~20 to 100% mass loss at 12 weeks) based on the extent of acrylation (~1 to 24%). These macromers were processed into biodegradable fibrous scaffolds using electrospinning, with gelatin as a carrier polymer to facilitate fiber formation and cell adhesion. The resulting scaffolds were also diverse with respect to their mechanics (tensile modulus ranging from ~60 kPa to 1 MPa) and degradation (~45 to 70% mass loss by 12 weeks). Mesenchymal stem cell adhesion and proliferation on all fibrous scaffolds was indistinguishable from controls. The scaffolds showed similar diversity when implanted on the surface of hearts in a rat model of acute myocardial infarction and demonstrated a dependence on scaffold thickness and chemistry in the host response. In summary, these diverse scaffolds with tailorable chemical, structural, mechanical and degradation properties are potentially useful for the engineering of a wide range of soft tissues.