Abstract. 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. In this talk, I will introduce a voxelated bioprinting technology that enables the Digital Assembly of Spherical bio-ink Particles (DASP). First, I will discuss the criteria for the on-demand generation, disposition, and assembly of viscoelastic bio-ink droplets 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 into multiscale porous scaffolds to treat type 1 diabetes. I will also discuss immediate applications and emerging challenges associated with voxelated bioprinting.

Bio. Liheng Cai is an Assistant Professor at the University of Virginia (UVA), where he currently holds joint appointments in the Department of Materials Science and the Department of ChemicalEngineering, as well as a courtesy appointment in the Department of Biomedical Engineering. He received his Ph.D. in Materials Science from the University of North Carolina, where he conducted research with Prof. Michael Rubinstein on theoretical polymer
physics and with Prof. Richard C. Boucher on experimental biophysics. During his postdoctoral training with Profs. David Weitz and Jeffrey Freberg at Harvard, he transitioned to experimental research. Since 2018, he has been leading the Soft Biomatter Laboratory at UVA, where his group focuses on understanding and controlling the interactions between soft (bio)materials and living systems, with the mission of addressing challenges in sustainability and health. He has received North Carolina Impact Award, Harvard Postdoctoral Award for Professional Development, NSF CAREER Award, NIH Maximizing Investigators’ Research Award (MIRA), ACS PRF Doctoral New Investigator Award, ACS PMSE Early Investigator Award, and UVA Research Excellence Award. Additionally, he has been recognized as a Soft Matter Emerging Investigator and an ACS Polymers Au Rising Star.