Regulated Insulin Delivery From Glucose-responsive Core-shell Microspheres Prepared By Emulsification

Diabetes is a disorder of blood glucose metabolism,which leads to hyperglycemia in human blood glucose over a long period of time and has become one of the three major diseases that endanger human health.For type I and advanced type II diabetes patients,the most effective treatment currently is multiple subcutaneous injections of insulin and regular monitoring of blood glucose levels.However,this therapy is inconvenient and painful and needs to rely on the patient's own operation.More importantly,the glucose level change and drug therapy are not directly coupled in this conventional treatment and cannot strictly control the patient's glucose level.Therefore,researchers have developed a variety of glucose-responsive insulin delivery systems.The controlled release system continuously and automatically performs insulin delivery,responding appropriately to changes in glucose levels.In recent years,personalized treatment based on the individual needs of patients has received more and more attention in the treatment of diabetes,which can help diabetics achieve accurate blood glucose control,improve insulin sensitivity and reduce the risk of complications.Therefore,the development of a glucose-responsive insulin delivery system to enable the composition of the hydrogel network to achieve the desired response rate according to the individual needs of each patient has a great demand for customization.This paper started with the response mechanism of Con A-dextran system,and successfully prepared Con A-dextran glucose-responsive insulin-loaded microspheres by W/O emulsification method,and in-depth discussed the influence of differences in formula composition on the response behavior of microsphere systems.On one hand,the regulation of the response behavior of the Con A-dextran system was achieved by the adjustment of the formulation composition.On the other hand,the glucose-responsive core-shell microspheres with light-responsive polymer shells were successfully prepared by the S/O/W double emulsion method,which further regulated the release rate of insulin and glucose-responsive release patterns.The addition of light-responsive shells reduced the burst release effect of the core-shell microspheres,prolongs the cumulative release time,and reduces the amount and rate of insulin release,thus realizing the concept of light-regulated glucose-responsive release behavior.In addition,it has been verified that the insulin released from the microspheres remains active and the microspheres are not toxic to HDF cells.