Figure 14.

High-resolution 3D printing. (a) Solid hydrogel constructs generated by lithography-based biofabrication by DLP: (i–iii) pyramid, (iv–vi) cone, (vii–ix) flower with channels ranging from 50 μm to 500 μm. Adapted with permission from [342]. Copyright © 2018, IOP Publishing Ltd. (b) SEM images of high-resolution periodic structures fabricated via two-photon polymerisation, consisting of parallel lines and vertical pillars. By adjusting the laser focus during the printing process, it was possible to transition between undefined structures, in which the lines and the pillars were not distinguishable (i,ii), to well-defined periodic arrays, where the pillar and line organisation was well discernible (iii–v). (vi) displays the entire 3D-printed array. Adapted from [347] under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/). Copyright © 2019, Zheng, et al.