Figure 7.

Printing heterogeneous constructs through coaxial microfluidic printheads. (A) Schematic of the coaxial microfluidic printhead. (B) Photograph of the coaxial microfluidic printhead. Scale bar=1 cm. (C) Heterogeneous grid structure (25 layers) printed through using the coaxial microfluidic printhead. Scale bar=2 mm. (D) Schematic of rotating substrate for creating concentric ring “on-the-fly.” (E and F) Fabrication of a heterogeneous concentric ring. Scale bars are 2 mm and 1 mm, respectively. (G) Fabrication of multicellular (H9C2 and HUVEC) concentric rings through coaxial microfluidic printhead. Scale bar=4 mm. (H and I) Fluorescence microscopy image (top view) of multicellular rings. Scale bars are 1 mm and 500 µm, respectively.