To test the safety of the insulin-loaded PAM-PAspPBA-b-PEG in mice, we determined that the injection of insulin-loaded PAM-PAspPBA-b-PEG did not cause death in the normal mice, whereas the injection of pure insulin at identical dosage caused the death of 50% mice due to hypoglycemia (Figure 6A). Here, INS is linked to Hypoglycemia.