Figure 4.

Viability of cells grown on MDP hydrogels. RAW 264.7 cells were seeded on top of 70 μL of hydrogel pucks under 200 μL of media (changed every 2 days) and processed under live–dead viability assays (green Calcein AM: live cells; red ethidium homodimer I: dead cells; blue Hoechst 33342: nuclei). Cells are shown to be able to attach and proliferate on all materials, though to a lesser degree on the anionic MDP hydrogel E2 compared to the cationic MDPs R2, K2, and l-NIL-MDP. Day 1 images are shown on the top row, day 3 images are shown on the bottom row, and quantification of cell viability is shown on the right [values are mean ± standard deviation (SD) with n = 3 images]. All scale bars are 50 μm.