Freeform vascular microchannels within the aqueous environment play a crucial role for the scalability in tissue engineering, yet they remain challenging to fabricate. Carbohydrate glass materials have shown potential for 3D printing precise, microscale structures and are suitable as sacrificial material to reconstruct complex channel architectures, but due to the rapid dissolution kinetics in hydrogels and aqueous environment, protective coatings are required. Here, we report a universal method to form conformal coatings via surface-initiated polymerization (SIP) by incorporating photoinitiator (PI) into complex, freeform 3D printed isomalt structures. A dye-based, type-two photoinitiator, Eosin Y disodium salt (EY), was selected for its miscibility with isomalt and stability under high temperature. A previously described Eosin Y (EY)/triethanolamine (TEA) radical polymerization system was used to polymerize poly (ethylene glycol) diacrylate (PEGDA). ATR-FTIR, surface morphology, swelling ratio, and thickness characterizations via SIP were performed. Coatings around freeform structures and solid surfaces were presented to demonstrate the capability of coating complex architectures. Furthermore, the coating method was used to regulate cell adherent properties on arbitrary surfaces<b>. </b>Enhanced cellular adhesion was observed by directly coating a layer of cell-laden gelatin methacryloyl (GelMA) via surface-initiated photopolymerization around PEGDA materials. This coating method should enable application of 3D sacrificial molding in a variety of hydrogels towards building biomimetic vascular constructs.

Surface-initiated photopolymerization for microchannel fabrication and enhanced cell adhesion on complex 3D printed substrates

ACS Spring Meeting 2021

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