Erythrocyte-mimicking subcutaneous platform with a laser-controlled treatment against diabetes

Exogenous insulin (INS) is critical for managing diabetes. However, owing to its short in vivo half-life, frequent injection of INS is un-avoidable, which is both painful and inconvenient, compromising the quality of life. Herein, we developed a laser-regulated INS release system (INS-ICG@ER hydrogel) that allowed an on-demand release of INS from the subcutaneous INS reservoir by remote laser control without the frequent injection of INS. The amino acid hydrogel functions as a hydrogel 3D scaffold material, which offers increased subcutaneous stability of drug loaded erythrocytes (ER). This INS-ICG@ER hydrogel would release INS due to the elevated content of reactive oxygen species (ROS), generated by ICG under laser irritation. Conversely, the ROS would be scavenged without the laser irradiation and stopped the release of INS from INS-ICG@ER hydrogel. Furthermore, the release of INS from INS-ICG@ER hydrogel could be regulated by laser irradiation. The INS-ICG@ER hydrogels could control the hyperglycemia within 2 h in diabetic mice and maintained their normal blood glucose level (BGL) for up to 6 days with laser irradiation 30 min prior to meals avoiding the frequent injection of free INS. This delivery system is an effective method that offers a spatiotemporally controlled release of INS to control the glucose level in vivo.