Rubina Ajdary, Siqi Huan, Nazanin Zanjanizadeh Ezazi, et al.
Many types of bioinks require stabilization after bioprinting to maintain construct geometries. Stabilization can be achieved by adding components that can result in complex rheological properties or by including additives that may not be cell supporting. The development of single-component bioinks that can be stabilized is of importance to help simplify the bioprinting workflow. Furthermore, when fabricating constructs for implantation, the cost and sourcing of materials becomes critical. In particular, there is a need in bioprinting to develop bioinks that are both sustainable and scalable in their production but also can have consistent properties.
The team at Aalto University used nanocelluloses (CNF) obtained from trees that could be modified through acetylation. This source is sustainable and widely available and can be easily controlled. Several formulations of bioinks were based on this nanoceullose-based material and evaluated, including unmodified CNF, Acetylated CNF (AceCNF), and TEMPO-oxidized CNF (TOCNF). There were used and prescreened using rheological techniques, then their printability was confirmed using the BIO X system. The best bioink formulations based on each material were fabricated into porous lattice constructs to be evaluated for their geometry and stability when lyophilized and rehydrated. The BIO X allowed them to compare each material with consistent prints and to automate the fabrication process.
The resulting constructs were fabricated from a single-component bioink and exhibited stability after printing, as well as during and after lyophilization. Cell viability testing confirmed that cells were compatible with myoblastic cells for up to 21 days, indicating that cells interacted with and proliferated on the constructs. Additionally, the constructs were shown to be nontoxic to the cells. Confirmation of the stability after rehydrating showed that these bioinks and this technique can be used for the inexpensive and consistent fabrication and storage of constructs that can be used as base materials for cardiac regeneration.
Acetylated nanocellulose for single-component bioinks and cell proliferation on 3D-printed scaffolds. Biomacromolecules. 2019; 20(7): 2770. DOI: 10.1021/acs.biomac.9b00527