On-demand serum-degradable amylopectin-based in situ gellable hydrogel

This paper describes the hydrogels which are quickly degradable, even on-demand, by exposure to serum, as well as in situ gellable under mild conditions for cells. In addition, potential applications of these hydrogels to tissue engineering and regenerative medicine are also described. The hydrogels were produced from aqueous solution of amylopectin derivatives bearing phenolic hydroxyl moieties (AP-Ph) via horseradish peroxidase-catalysed reaction. The degradation rate in the presence of serum was enhanced with increasing the content of fetal bovine serum (FBS) and decreasing the content of Ph moieties in AP-Ph. A 1 mm thick hydrogel enclosing mouse embryonic fibroblast STO cells prepared under conditions giving gelation in about 30 s disappeared within 3 h of incubation in FBS. The cells released from the hydrogel attached onto a culture dish and showed similar morphology to those seeded without being enclosed in the hydrogels. Furthermore, confluent human epithelial cells cultured on the AP-Ph-based hydrogel in serum-free medium can be harvested within 10 min by soaking in FBS while without separating into individual cells. These results indicate that the in situ gellable serum-degradable AP-Ph hydrogels may be a promising new tool for tissue engineering.