Preparation of an enteric-soluble solid-state emulsion using oily drugs

To improve the patient's compliance and enhance the stability of oily drugs in the gastric fluid, an enteric-soluble solid-state emulsion (ESE), was developed. The ESE was prepared by spreading liquid o/w-emulsions on a flat glass and drying at the oven maintained at 40 °C. Aerosil 200 was applied as solid carrier and emulsifier. And Eudragit® L30D-55 was used as enteric coating material. The influence of various preparation parameters on the residual volatile oil and the release behavior was investigated. Droplet size distribution of the primary emulsions and the emulsion after reconstitution of zedoary turmeric oil (ZTO) ESE in the phosphate buffer were also measured. When ZTO ESE was immersed into phosphate buffer (pH 6.8), the stable emulsion was formed in 20 min, but the release was obviously suppressed when it was exposed to the gastric fluid. It was concluded that preparation of enteric-soluble solid-state emulsion by the present method for oral oily drug was feasible.