Fig. 6. Live h-FOB cells area (calcein-AM assay) cultured on 2D peptide hydrogels after 5 days. (A) Ratio between areas of live cells on FD or 25 mol% FD-RGD hydrogel to total live cells area, ***p < 0.001, n = 3. Images of cells stained live (green) cultured on (B) FD hydrogel and on (C) 25 mol% FD-RGD. (D) Number of cells stained by DAPI (blue, as part of Focal Adhesion Staining Kit, see Experimental) relative to hydrogel area of FD and 25 mol% FD-RGD peptide hydrogels labelled with fluorescent rhodamine-B (red), after 24 h culture, *p < 0.05, n = 3. Yellow which indicates merge between red (hydrogel) and green (staining vinculin by the kit) was not used for analysis due to low contrast between the different shades of the red hydrogels and the yellow colour. (E) Images of cells over FD and (F) over 25 mol% FD-RGD. Scale bar = 100 μm, two-tail student test, SEM in errors bars. Noteworthy, there was no significant difference in overall cell viability between FD and 25 mol% FD-RGD (see ESI S6†).