ABSTRACT
Many therapeutically active agents are limited in their clinical use because of the obscure delivery processes and methods for the specific sites of action, but there are many offpatent safe drugs whose usefulness and strength would be extended by a new type of formulation. Further, the efforts to develop delivery systems would be much less than those involved in developing a new drug [1]. Therefore, there have been continuous attempts to develop new delivery methods and to design special carriers that would uniquely guide drugs specific to target cells and tissues as well.
