The Preparation Of Gel W/O/W Multiple Emulsion Loaded Insulin

Insulin is one of the most important drugs to cure diabetes. Presently, insulin is mostly given to patients by injection in clinic, and too much injection per day causes patients pain and some accompanying side effects. The problem can be solved by oral administration of insulin. But, insulin generally exhibits poor bioavailability on oral administration. The poor bioavailability has been attributed to the extensive hydrolysis of insulin by the proteolytic enzymes in the gastrointestinal (GI) tract and a poor membrane permeability because of high molecular weight. To overcome problems of absorption via the GI tract, various strategies, such as the use of absorption enhancers and protease inhibitors dosage form and chemical modification have been tried. Researchers hope insulin oral administration become possible by using the proper concealment and protection and absorption enhancer. Water-in-oil-in-water (W/O/W) multiple emulsions were thought to be an effective dosage form as an enteral carrier of insulin because they could protect insulin against proteolysis. In this paper , W/O/W multiple emulsion is investigated to loaded insulin and an original idea gel multiple emulsion is put forward.This paper investigates several oils, surfactants and their combinatorial relations, and the liquid Paraffin-water- Span 80&Abil EM 90- Tween80 are determined in the process of W/O/W multiple emulsion preparation. Through orthogonal experiment design and single parameter analysis, the optimal preparation method is determined. And a small mean size, homogeneous distribution and good stable W/O/W multiple emulsion loading insulin is prepared.Meanwhile, this paper probes into how the factors in the preparation influence the activity of the insulin using HPLC. The experimental results indicate that the insulin still keeps its activity under different circumstance as at different temperature in water and under magnetic stirring at speed of 3000rpm. As well the insulin does not lose its activity due to the effect of oil and surfactants. The experimental results indicate that the insulin encapsulation efficiency is 93.2% by using the gel multiple emulsion prepared.Through the studies on mixture of Konjac gum with Carrageenan, Xanthan gum, Sodium Alginate, Gelatin, arabic gum and Sodium Caseinate, a intensity synergistic effect of Konjac gum and Xanthan gum have been founded. The optimal proportion is that the complex Konjac Gum consisted of 20% Konjac gum and 80% Xanthan gum. And a gel multiple emulsion is prepared.The experimental results in vitro release indicate that W/O/W multiple emulsion can protect insulin against proteolytic enzymes in the gastrointestinal tract and it can release insulin in artificial intestinal juices. The gel multiple emulsion not only increase the stability of the system, but also behave the same function with the W/O/W multiple emulsion in the simulate gastrointestinal tract.Though the investigations above, a complex Konjac gum & Xanthan gum gel multiple emulsion is prepared. This system perform the stability character of the gel in shelf life, and perform the control release character of W/O/W multiple emulsion in the simulate gastrointestinal tract. This The conclusion provides good foundation for the future study.