Figure
5 Construction of 3D architectures via layer-by-layer adhesion.
(A) 3D architecture constitutes hydrogel strips. (B) The chip with
vascular-like microchannels comprises three parts of hydrogels.
We also used this method to construct perfusable microfluidic chips with
complex channels. After sealing by CS-MA, the F127-DA/PAAm and
PEG-DA/PAAm chips were obtained with corresponding microchannels (Figure
6A and 6B). By perfusion of red Rho B solution, the microchannels
revealed with snail and spiral morphology (Supplementary Movie 4). These
complex channels with sharp turns still performed at high resolution,
which was better than those made by sacrificial templates6,12 and 3D printing 15. Another
example was a bilayer chip that was commonly used for coculture of
cells. As shown in Figure 6C, a PAAm film was stitched between two
F127-DA hydrogels, where the bilayer microchannels could be perfused
individually.