Voxelated Bioprinting: Digital Assembly of Viscoelastic Bio-ink Particle*

Analogues of pixels to two-dimensional (2D) pictures, voxels –– in the form of small cubes or spheres –– are the basic units of three-dimensional (3D) objects. Digital assembly of bio-ink voxels may provide an approach to engineering heterogeneous yet tightly organized 3D tissue mimics. However, this approach requires precisely manipulating highly viscoelastic bio-ink voxels in 3D space, which represents a grand challenge in both soft matter science and biomanufacturing. Here, we introduce a voxelated bioprinting technology that enables the Digital Assembly of Spherical bio-ink Particles (DASP). First, I will discuss the criteria for printing viscoelastic bio-ink droplets with good fidelity in an aqueous environment without the help of large interfacial tension. Second, I will describe how to use DASP to create 3D structures consisting of interconnected yet distinguishable bio-ink particles. Finally, I will share our recent progress in applying DASP to encapsulate islets in multiscale porous scaffolds to treat type 1 diabetes. I will also discuss immediate applications and emerging challenges associated with voxelated bioprinting.