A review of enzyme immobilization technology in continuous glucose monitoring systems

Diabetes mellitus has emerged as a globally prevalent chronic metabolic disorder, characterized by persistent hyperglycemia and associated complications. Continuous glucose monitoring is a technology that continuously monitors blood glucose by implanting microelectrodes under the skin, which is the most common method of diabetes treatment. Due to the discomfort caused by frequent blood collection through traditional blood glucose monitoring, continuous glucose monitoring has become a major research focus, mainly relying on blood glucose biosensors. In this paper, the progress of electrochemical biosensors in continuous glucose monitoring systems and the characteristics of electrochemical biosensors in different stages of development were mainly summarized. The commonly used enzyme immobilization technology aiming to solve the problems of enzyme leakage, activity decrease, and sensitivity decline caused by long-term subcutaneous implantation of blood glucose biosensors were discussed, meanwhile, the advantages and disadvantages of the different methodologies were also compared. These methodological advancements provide critical insights for optimizing biosensor stability and durability, establishing a theoretical foundation for developing next-generation implantable continuous glucose monitoring devices with enhanced clinical performance.