Shuai Li, Kan Wang, Xuzhou Jiang, et al.
Researchers at the Georgia Tech Manufacturing Institute sought to improve the resulting cellular compatibility of vascularized bioprinted constructs generated with sacrificial bioinks. Any interpenetrating networks formed at the interface region between the sacrificial component and the construct remains after stabilization and dissolution and can result in different properties of the network that affect cell adhesion, mechanical characteristics and protein absorption. These challenges can make it difficult to endothelize the interface or study applications such as cancer metastasis or drug-barrier crossings.
The CELLINK BIO X bioprinter was used to extrude and deposit various solid and hollow alginate tubes through a custom coaxial printhead. These alginate fibers and tubes were then encapsulated in a custom bioink to simultaneously crosslink the gelatin bioink and dissolve the alginate sacrificial component. By optimizing the diameter of the alginate filaments and the crosslinking rates of the bulk and the dissolution rate of the alginate, they were able to determine what was the optimal bioink and conditions to improve cell adhesion and endothelization.
Hollow alginate tubes extruded using a coaxial printhead were determined to generate better resulting channel geometry and also dissolved without leaving as much residue behind as solid alginate filaments. This was shown to be beneficial because of high levels of HUVEC adhesion and the formation of a dense layer that otherwise would have been inhibited by residue on the surface.
Rapid fabrication of ready-to-use gelatin scaffolds with prevascular networks using alginate hollow fibers as sacrificial templates. ACS Biomaterials Science & Engineering. 2020; 6(4): 2297. DOI: 10.1021/acsbiomaterials.9b01834.