Design and development of transdermal drug delivery system.

In the course of development of microspheres preparation techniques, the encapsulation of hydrophilic drugs with high entrapment efficiency has been a problem, as the commonly used technique like single emulsification technique and w/o/w double emulsification technique show low entrapment of the hydrophilic drugs. The problem is overcome by using by using w/o/o double emulsification technique, several modifications have been done in this technique one of most widely and effective technique in w/o/o double emulsification is the solvent diffusion technique. In this brief review comparison of w/o/o double emulsification technique with other methods and details about the w/o/o double emulsification technique and the drugs encapsulated using this technique will be discussed.