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.