(511d) Hierarchically Patterned Microfibers Via 3D Jet Writing

Jordahl, J., University of Michigan
Ramcharan, S., University of Michigan
Solorio, L., University of Michigan
Teeple, C., University of Michigan
Lahann, J., University of Michigan

Electrospinning of polymer fibers is a technique that has been in use for nearly a century, and has recently been a popular platform for creating tissue engineering scaffolds. However, the use of these fibers is quite limited due to the inability to precisely control the fiber architecture. Electrohydrodynamic (EHD) co-jetting is a method of creating compartmentalized polymer fibers which allows multiple surface chemistries, mechanical properties, polymer degradation, or drug loadings to be confined into separate continuous compartments in a single fiber. Utilization of EHD co-jetting combined with a newly developed method for patterning polymer fibers via an ultra-stabilized jet has been used to create hyper-porous polymer scaffolds of multi-compartmental fibers. The combination of multicompartmental fibers and the direct fiber writing process provides a platform for controlled anisotropy, geometries, pore sizes, surface functionalities, and mechanical gradients independently on a single 3D structure. These scaffolds provide a platform technology that can be used to modulate multiple parameters simultaneously and repeatedly to more accurately recapitulate a cell's native environment. To demonstrate the fiber scaffolds can produce viable engineered tissues, the scaffolds were used to culture human mesenchymal stem cells (hMSCs) into thick tissue-like sheets. The hMSCs were subsequently osteogenically differentiated, and were implanted into a calvarial defect in nude mice for eight weeks. This system was able to generate new bone across a 3 mm defect in the mouse's skull using differentiated hMSCs grown on the fiber scaffolds.