Theoretical studies on self-regulating insulin delivery system

A theoretical analysis of a self-regulating insulin delivery (SRID) system was made using published in vitro results. The SRID system consists of an encapsulated glycosylated insulin bound to concanavalin A (conA) that exchanges insulin with glucose through a reversible chemical reaction between glucose and conA-insulin (C-I). The mathematical analysis of the in vitro results gave the values of the forward and reverse reaction rate constants. Using these calculated reaction rate constants, the insulin release rate was predicted from a SRID cylindrical pouch in response to a change in glucose concentration. The insulin release rate was found to be strongly affected by the diffusivity coefficients of insulin and glucose within the pouch, the radius of the pouch, membrane permeability, C-I concentration, and the kinetic rate constants. This mathematical analysis provides useful guidelines for the rational design of the SRID system.