The shape of the vesicles became distorted as we increased the pressure from 2.9 to 12.8 kPa and about 33% of the monitored (n = 12) vesicles lost their internal fluorescence signal with flattened membrane shape, indicating vesicle rupture (Figure ). These results confirmed that the vesicle-containing hydrogel can be used as an on-demand mechano-responsive system that stably retains and releases the loaded compounds inside the vesicles in the absence and presence, respectively, of external mechanical stress.