Intranasal Delivery of Insulin via Microemulsion-based Formulation

Keywords:
Insulin, diabetes, microemulsion, intranasal delivery

Abstract:
Nasal drug administration has been proposed as an alternative to parenteral injection. Because of their unique solubilization and permeation enhancing properties, microemulsions possess a great potential as an intranasal drug delivery system for insulin. The most common regimen of insulin treatment is the subcutaneous injection of fast acting insulin preprandial. We developed a novel microemulsion which eliminates the use of integrated alcohol or other irritant chemicals and contains GRAS compounds. Two microemulsion types were prepared, ME-50 and ME-20, containing 50 and 20% aqueous phase, respectively. Four different administrations were tasted on six diabetic New Zealand White rabbits: subcutaneous injection of 0.5 I.U/kg Humalog solution, intravenous injection of 0.5 I.U/kg Humalog solution, intranasal administration of 1 IU/kg microemulsion type MEIN-50 (40µL/one nostril), and intranasal administration of 1 IU/kg microemulsion type MEIN-20 (50µL/nostril X 2 nostrils). Blood samples were collected for further ELISA analysis. Intranasal application resulted in a faster tmax than subcutaneous injection (15.00±0 vs. 27.5±11.29 min), the relative bioavailability (as compared with subcutaneous administration) and the absolute bioavailability (as compared with intravenous administration) found to be 21.53% and 41.82%, respectively. The present results clearly show that the new microemulsion possesses a great potential for the treatment of diabetes patients.

Nanotech 2008 Conference Program Abstract