Functional macromolecular platforms: hydrogel and soluble polymer-based materials for biomedical applications

Abstract

Design, fabrication and applications of novel hydrogel and soluble polymer-based macromolecular platforms employing functional polymer building blocks are described. Several click chemistry-based transformations and post-polymerization modification techniques have been evaluated in fabrication of chemically cross-linked hydrogels. In conjunction with novel design of reactive polymeric materials, hydrophilic linear polymers with clickable functionalities were synthesized and used in various applications. In the first study, fabrication of well-defined chemically cross-linked poly(ethylene glycol) (PEG)-based hydrogels using the thiol-maleimide addition reaction is reported. Hydrogels obtained by crosslinking of homobifunctional PEGs and a multifunctional β-cyclodextrin-based (β-CD) crosslinker were evaluated in post-gelation modification reactions. In the second project, fabrication of poly(ethylene glycol)-based chemically cross-linked hydrogels containing discrete β-CD units is outlined. Various hydrogels obtained by radical thiol-ene reactions were investigated in terms of their physical gel properties as well as uptake and controlled release of a hydrophobic drug molecule. The third project involves the utilization of reversible addition−fragmentation chain-transfer polymerization-mediated homotelechelic and hetero telechelic polymers toward post-polymerization functionalization with thiol-containing molecules, as well as fabrication of hydrogel networks. In the fourth project, design, synthesis and post-polymerization functionalization of linear PEG-based polytriazole copolymers containing thiol-reactive functional groups as pendant side chains is described. These polymers were utilized in functionalization via click chemistry-based transformations and fabrication of chemically cross-linked functionalizable hydrogels. The fifth project outlines the synthesis of novel thiol-reactive polymers containing a catechol moiety and demonstrates their application towards surface modification of magnetic nanoparticles. The final project describes the synthesis of novel polymers containing activated carbonate groups at side chains and demonstrates their application towards the preparation of polymer-drug conjugates.