To explore the potential of our 3D printing approach in biomedical applications, we tested the in vitro cytotoxicity of the 3D printed PEG networks using different resin formulations. The 3D printed discs from PEGDMA 10k -PEGDA 700 (80/20, w/w) or PEGDMA 6k -PEGCOOH (90/10, w/w) were incubated with A549 cells for 48 h using Transwell ® inserts, and the cell viability was determined by the MTS assay and compared to negative control. As shown in Figure , ~100% cell viability was observed for the hydrogel disks, indicating the cytocompatibility of the tested PEG networks.