Self-regulated delivery of insulin from microcapsules.

We previously developed self-regulating insulin delivery systems using concanavalin A (Con A)-bound succinyl-amidophenyl-glucopyranoside insulin (SAPG-insulin) in pouch membrane which exhibited long lag times for exchange diffusion in response to glucose changes. We report here the preparation of a new system with a short exchange diffusion onset composed of hydrophilic nylon microcapsules containing Con A and SAPG-insulin in vitro. It is considered that this SAPG-insulin system can quickly respond to glucose changes when it is composed of at least two layers which include active Con A and where unbound SAPG-insulin permeation is the rate limiting step.