Biodegradable polymer scaffolds for tissue engineering can be functionalized with specific chemistries to direct desired cell response. These scaffolds are typically modified post-fabrication, which can lead to undesirable changes in scaffold properties. In addition, most functionalization strategies result in homogeneously distributed chemistries that fail to mimic the biochemical organization found in native tissues. To address these challenges, we developed a versatile platform where end-functionalized polymer conjugates are 3D printed into well-defined patterns. The end groups on the conjugate became displayed on the surface during fabrication to generate functionalized scaffolds in a single step without affecting bulk scaffold morphology. The surface concentration of the functional groups was controlled by simply changing the conjugate concentration in the “ink” prior to 3D printing. Here, we synthesized peptide-polymer conjugates bearing two different sequences: (1) a cartilage-promoting peptide or (2) a bone-promoting peptide. Separate printer heads were used to localize each peptide in discrete regions of the same scaffold to mimic the osteochondral (bone-cartilage) interface. Human mesenchymal stem cells (hMSCs) were seeded in the spatially organized scaffold to investigate how dual-peptide organization influences cell response and matrix formation. We discovered that the presence of both peptides significantly affects hMSC differentiation compared to scaffolds presenting no peptide or only one peptide. Interestingly, scaffolds presenting both peptides homogeneously induced a different cellular response compared to scaffolds with spatially organized peptides. These results indicate that peptide organization influences local and global cell-material interactions and can be exploited to direct desired cell behavior.

End-functionalized polymer conjugates for spatially organized 3D-printed biomaterials

ACS Spring Meeting 2021

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.