Figure 4.

Printing of hollow constructs using sacrificial materials: The fabrication of constructs with hollow voids is possible using a sacrificial material such as pluronic. First, the sacrificial material is printed in the desired shape of the final void. Then, the scaffold material is cast or printed atop and around the sacrificial material. Finally, the sacrificial material is removed, following the solidification of the scaffold material. This leaves a construct with a void in the negative shape of the architecture printed using the sacrificial material. This is useful for fabricating micro- and millifluidic devices and emulating larger vascular units.