Fig. 2.

Illustration of the single and multilayer vascular-like structures, a a tubular Channel fabricated in bare GelMA: (i) phase contrast images of a 200 µm channel in bare GelMA, (ii) fluorescent image after flowing FITC through a 200 µm channel in GelMA; b a single layer vascular-like construct; (i) fluorescent image of top view of the vascular-like structure with green fluorescent beads encapsulated in the wall, (ii) cross-sectional side view of the structure showing the lumen and the wall of the construct; c a multilayer vascular-like structure: (i) top view bright field image of the bilayer structure, (ii) top view of the bilayer structure with fluorescent beads of different colors encapsulated in different layers, (iii) cross-sectional side view of the structure showing the lumen and the two layers of the wall. Scale bars = 200 µm