3D Bioprinting of Cellulose Structures from an Ionic Liquid
Journal article, 2014
This article reports on 3D bioprinting of dissolved cellulose to produce small feature structures with a tailored design of
regenerated cellulose. The process consists of dissolving cellulose with different origins and molecular weight in an ionic liq
uid
(1 - ethyl - 3 - methylimidazolium acetat
e), controlled multilayered dispensing, and coagulation. The printability was examined by
studying the viscosity of cellulose solutions and by varying the settings of the printer setup regarding flow rate and needle
dimensions. Water was added as a nonsolvent, enab
ling a coagulation process to form a gel structure of the printed solutions.
By printing on a coagulating gel, the printed solutions were regenerated within a few seconds. Rheology analysis showed that
higher concentrations of cellulose and cellulose of a high molecular weight were shear thinning, providing favorable printing
properties. Printing 3D structures of cellulose dissolved in an ionic liquid followed by coagulation by a nonsolvent was possib
le.
Both complex patterns of 2D structures as well as multilayered prints were created to obtain 3D structures. This novel method
allows for the production of spatially tailored 3D gels or membrane structures made from cellulose.