Formulation and Evaluation of Self‐Regulated Insulin Delivery System Based on poly(HEMA‐co‐DMAEMA) Hydrogels

In the present work a self‐regulated insulin delivery system based on the hydrogel poly(2‐hydroxyethyl methacrylate‐co‐N,N‐dimethylaminoethyl methacrylate) with entrapped glucose oxidase, catalase and insulin was developed and evaluated both by in vitro and in vivo studies. The hydrogels were characterized by FTIR, DSC, SEM and elemental analysis. The swelling studies were carried out in different pH and glucose solutions. The mesh size of the hydrogels and diffusion coefficient of water and insulin in different glucose solution was calculated. The effect of the crosslinking agent (ethylene glycol dimethacrylate) concentration (0–2% w/w) on swelling and insulin release was studied. The equilibrium swelling and insulin release was found to depend on the external glucose concentration and dimethylaminoethyl methacrylate content of the hydrogels. The in vivo studies indicated that the entrapped insulin was stable and was effective in reducing the blood glucose of streptozotocin induced diabetic rats. The histopathological studies revealed that there was no fibrous tissue encapsulation after 56 days of implantation.

Keywords:

• insulin
• self‐regulated
• swelling
• biocompatibility
• hydrogels

5 Acknowledgements

The authors wish to thank Principal of J.S.S. College of Pharmacy, Mysore and J.S.S. Mahavidyapeetha, Mysore for their encouragement and University Grants Commission (UGC) for funding the project.