MORE | Spring 2022

Expanding Injection Molding Biofabrication to Generate Complex Three-Dimensional Cell Encapsulation Geometries

Encapsulation is a promising technology to deliver cell-based therapies to patients safely and with reduced need for immunosuppression. Macroencapsulation devices are advantageous due to their ease of retrieval, and thus enhanced safety profile, relative to microencapsulation techniques. A major challenge in macroencapsulation device design is ensuring sufficient oxygen transport to encapsulated cells, requiring high surface-area-to-volume device geometries. In this work, we modify an injection molding biofabrication method to design and generate complex three-dimensional macroencapsulation devices that have greater complexity in the z-axis. Evaluation of the rheological properties of diverse hydrogels was used to perform computational flow modeling within 3D printed device designs and evaluated the reproducibility of filling and extraction. This work demonstrated that injection molding biofabrication to construct complex three-dimensional geometries is feasible in pressure regimes consistent with preserving cell viability. Future work will evaluate encapsulated cell viability after the injection molding.