Figure 1.

Schematic illustration of sEV preservation in GelMA hydrogels. sEV in PBS continuously move around in random patterns leads to particles aggregation, which resulted in membrane rupture (left). GelMA hydrogels could effectively limit the movement of sEV and reduce the aggregation to effectively preserve sEV. The preserved sEV were isolated for functional evaluation in vitro and UV-crosslinking sEV-GelMA complex system was adopted to compare the biological function of preserved sEV and fresh sEV in vivo (right).