Perfusion Directed 3D Bone Mineralization Using Custom-Modified 3D Printers

An inherent challenge in conventional tissue engineering strategies is the ability to efficiently deliver nutrients throughout the thickness of a complex, physiologically relevant biomimetic construct. In this work, we will present the creation of structurally supported, perfusable hydrogels capable of growing bone in user defined directions. Briefly, bone-like human osteosarcoma cells were encapsulated inside UV cross-linkable gelatin methacrylate (GelMA) hydrogels, and this cell-hydrogel mixture was casted onto a 3D printed poly(vinyl alcohol) (PVA) structure. PVA serves as a sacrificial material and was dissolved away to obtain hollow channels to facilitate the perfusion of media using a custom-made acrylonitrile butadiene styrene (ABS) bioreactor. Osteogenic media was perfused through the channels, and the radial zones of bone mineralization surrounding the channels were quantified. This study demonstrates that user-defined 3D printed channels can be used to spatially control bone mineralization.