Self-emulsification

Oral route has been considered as most convenient route but restricted to only hydrophilic compounds having GI stability and greater dissolution. The delivery of lipophilic compounds has been area of interest since most of the drugs under discovery shows limited bioavailability. Self-emulsifying delivery systems (SMEDDS) has drawn a greater attention in the formulation of poorly soluble compounds where increase in the absorption and permeation of the drug has observed. The self-emulsification which occurs in the case of SMEDDS has shown a potential advantage over conventional emulsion due to the fine globules formed upon dilution. The recent trends such as dry emulsion, s-SMEDDS, SNEDDS thoroughly investigated. This article, attempts to present the overview of the SMEDDS along with its formulation, application and characterization.

  The aim of this work was to develop a stable self micro emulsifying drug delivery system (SMEDDS) of herbal extract and evaluating its in vitro potential. The solubility of herbal extract was determined in various vehicles. Pseudoternary phase diagrams were used to evaluate the micro emulsification existence area. Release rate of herbal extract was investigated using a dissolution method. SMEDDS were characterized for clarity, precipitation and particle size distribution. Formulation development and screening was done based on results of solubility & from phase diagram. The optimized formulation used for in vitro dissolution was composed of herbal extract (30 %), Cremophor RH 40 (40 %), Plurol Oleique (30%). The SMEDDS formulation showed complete release in 10 min. as compared with the plain extract and conventional marketed formulation. SMEDDS subjected to various were conditions of storage as per ICH guidelines for 3 months. SMEDDS successfully withstood the stability testing. It has been found that dissolution profile of herbal extract from SMEDDS was much improved. SMEDDS appeared to be an interesting approach to improve solubility, and ultimately bioavailability Key words: SMEDDS; herbal extract; Pseudo-ternary Phase diagram; Self-emulsification