Preparation And Characterization Of Insulin Oil Solution

Macrasol, the technique which can make the macromolecule dissolve in oil phase, is a new drug carrier system for oral administration of protein or peptide. In this work, we screened out appropriate oil menstruum and technical conditions to get a satisfying insulin oil solution, which are prepared simply and show long term stability.The studies in vitro show that this formulation can self emulsified in water. The Eff. Diam. of the emulsified particles was about 300nm with narrow distribution after the insulin oil solution was dispersed in water with pH of 7.9. After emulsification in water, insulin in the oil can be protected from digestive enzymes in vitro.The biological effect of this formulation in normal mouse and diabetic rats after orally administrated was studied in this work. It showed a dosage dependent degrease of blood glucose level. The effect after intestinal administration is better than it after oral administration. There was a significant decrease of blood glucose level for about 24 hours after the Enteric-Coated Soft Capsules containing insulin oil formulation were orally administered to diabetic dogs (2.5IU/kg). The pharmacodynamic bioavailability of this capsule after oral administration related to NPH insulin after subcutaneous(SC) injection was 15.21%.Determination of insulin in oil phase was one important part of this work. We founded a suitable capillary electrophoresis method with high recovery of insulin and good repetition.