A Collagen-Conducting Polymer Composite with Enhanced Chondrogenic Potential.

INTRODUCTION: Conducting polymers (CPs) have demonstrated promise for promoting tissue repair, yet their ability to facilitate cartilage regeneration has yet to be thoroughly investigated. Integrating CPs into common scaffolds for tissue regeneration, such as collagen, would enable mechanistic studies on the potential for CPs to promote cartilage repair. Here, we combine absorbable collagen sponges (ACS) with the CP PEDOT-S and show that the PEDOT-S-collagen composite (PEDOT-ACS) has enhanced chondrogenic potential compared to the collagen sponge alone.
METHODS: PEDOT-S was incorporated through a simple incubation process. Changes to scaffold topography, elastic modulus, swelling ratio, and surface charge were measured to analyze how PEDOT-S affected the material properties of the scaffold. Changes in rat bone marrow mesenchymal stem cell (rBMSC) functionality were assessed with cell viability and glycosaminoglycan production assays.
RESULTS: Macrostructure and microstructure of the scaffold remained largely unaffected by PEDOT-S modification, as observed through SEM images and quantification of scaffold porosity. Zeta potential, swelling ratio, and dry elastic modulus of the collagen scaffold were significantly changed by the incorporation of PEDOT-S. Seeding cells on PEDOT-ACS improved cell viability and enhanced glycosaminoglycan production.
CONCLUSION: We demonstrate a practical approach to generate PEDOT-S composites with comparable physical properties to pristine collagen scaffolds. We show that PEDOT-ACS can influence cell functionality and serve as a promising model system for mechanistic investigations on the roles of bioelectronic signaling in the repair of cartilage and other tissue types. © Biomedical Engineering Society 2021.