Fig. 3. (a) Representative bright-field images of Oil Red O and Fast Blue salt-stained hMSC-hydrogel constructs following a 14 day incubation in bipotential differentiation media while exposed to different light conditions. Scale bar, 100 μm. Percentage of cells expressing neutral lipids (b) and alkaline phosphatase (ALP, c). Asterisks denote statistical significance compared with NIR hydrogels (**p < 0.05, t-test). Error bars represent standard error of the mean from 5 individual experiments.
