title: Freeform inkjet printing of cellular structures with bifurcations.
abstract: Organ printing offers a great potential for the freeform layer-by-layer fabrication of three-dimensional (3D) living organs using cellular spheroids or bioinks as building blocks. Vascularization is often identified as a main technological barrier for building 3D organs. As such, the fabrication of 3D biological vascular trees is of great importance for the overall feasibility of the envisioned organ printing approach. In this study, vascular-like cellular structures are fabricated using a liquid support-based inkjet printing approach, which utilizes a calcium chloride solution as both a cross-linking agent and support material. This solution enables the freeform printing of spanning and overhang features by providing a buoyant force. A heuristic approach is implemented to compensate for the axially-varying deformation of horizontal tubular structures to achieve a uniform diameter along their axial directions. Vascular-like structures with both horizontal and vertical bifurcations have been successfully printed from sodium alginate only as well as mouse fibroblast-based alginate bioinks. The post-printing fibroblast cell viability of printed cellular tubes was found to be above 90% even after a 24 h incubation, considering the control effect.
authors.affiliation: Department of Mechanical and Aerospace Engineering, University of Florida, Gainesville, Florida, 32611.
authors.forename: Kyle
authors.initials: K
authors.lastname: Christensen
authors.forename: Changxue
authors.initials: C
authors.lastname: Xu
authors.forename: Wenxuan
authors.initials: W
authors.lastname: Chai
authors.forename: Zhengyi
authors.initials: Z
authors.lastname: Zhang
authors.forename: Jianzhong
authors.initials: J
authors.lastname: Fu
authors.forename: Yong
authors.initials: Y
authors.lastname: Huang
mesh_terms: D000464:Alginates / Q000737:chemistry*; D000818:Animals; D021522:Bioartificial Organs; D001672:Biocompatible Materials / Q000737:chemistry; D062028:Bioprinting / Q000295:instrumentation / Q000379:methods*; D001808:Blood Vessels / Q000033:anatomy & histology* / Q000166:cytology* / Q000502:physiology; D002470:Cell Survival; D004867:Equipment Design; D005347:Fibroblasts / Q000166:cytology; D020723:Glucuronic Acid / Q000737:chemistry; D006603:Hexuronic Acids / Q000737:chemistry; D051379:Mice; D041681:NIH 3T3 Cells; D018919:Neovascularization, Physiologic; D023822:Tissue Engineering / Q000295:instrumentation / Q000379:methods*; D054457:Tissue Scaffolds / Q000737:chemistry*
chemical_list: D000464:Alginates; D001672:Biocompatible Materials; D006603:Hexuronic Acids; D020723:Glucuronic Acid
keywords: cell viability; inkjetting; liquid support; predictive compensation; three-dimensional bioprinting