Movie S1

Printing GelMA cylinders with an off-system photocrosslinking system. Off-system crosslinking was performed to demonstrate the ability to crosslink GelMA precursor above its gelling point. Off-system photocrosslinking was required to print the non-gelled GelMA because clogging occurred originally due to the intensity of the on-system photocrosslinking system. The same light source was moved further from the print (20 cm) to irradiate the whole printing field. The result was partially crosslinked cylinders that retained their structure, which could be further crosslinked after printing.