Metallo-elastomers for biomedical applications
Abstract
Elastomers are network polymers typically crosslinked by strong covalent bonds and are widely present in nature and in manufactured goods. Weak bonds can also crosslink elastomers, but the product usually exhibits more plastic deformation. Using coordination bonds to crosslink elastomers is a virgin territory. Here I report our exploration in chelation as a mechanism to produce biodegradable elastomers. Chelation offers a unique advantage in that one ligand binds multiple metal ions yielding bonds of different strengths. Therefore, one polymeric ligand coordinated with different metal ions produces polymers with vastly different characteristics. Those with strong chelation bonds match the low hysteresis of covalently crosslinked elastomers. Furthermore, chelation offers the opportunity to incorporate bioactive metal ions. I will discuss our work with copper which is pro-angiogenic and catalytically decomposes reactive oxygen species. Acellular vascular grafts made of the elastomer transform into autologous vascular conduits in vivo with robust expression of elastin. There are many elastic tissues in the human body. These biodegradable elastomers could enable new possibilities in treating disorders in soft tissues.
