An injectable self-healing hydrogel "Trojan Horse" for adjunctive therapy of colon cancer recurrence

Herein an injectable self-healing hydrogel via dynamic linkage of an imine bond based on a novel multi-aldehyde polyethylene glycol crosslinker was reported. The biocompatible crosslinker could be synthesized via easy chemistry on a large scale. After cross-linking with glycol chitosan, the self-healing hydrogel could be easily obtained in similar to 1 h under mild conditions. The prepared hydrogel showed satisfactory mechanical properties and ideal biocompatibility and was successfully used in an in vivo mouse model as a drug carrier just like a "Trojan Horse". It could deliver a highly concentrated anti-tumor drug (DOX) to the desired position for sustainable controlled release at a safe level. Compared with intravenous or intratumoral injection, the hydrogel drug carrier achieves an admirable therapeutic effect and collectively prevents the recurrence of colon cancer during the whole treatment process. Due to its excellent biocompatibility and good operability, this injectable self-healing hydrogel might be a promising drug carrier for surgical adjuvant treatment and other medical applications. This strategy may provide more insights for the design, study and application of new biomaterials.