Der Pharmacia Lettre
Ram Chand Dhakar, Sheo Datta Maurya, Bhanu PS Sagar, Sonia Bhagat, Sunil Kumar Prajapati, Chand Prakash Jain
Novel drug delivery systems have several advantages over conventional multi dose therapy.
Much research effort in developing novel drug delivery system has been focused on controlled
release and sustained release dosage forms. Now considerable efforts are being made to deliver
the drug in such a manner so as to get optimum benefits. There are various approaches in
delivering a therapeutic substance to the target site in a sustained controlled release fashion.
One such approach is using microspheres as carriers for drugs. Microspheres received much
attention not only for prolonged release, but also for targeting of anticancer drugs to the tumor.
Microencapsulation is used to modify and delayed drug release form pharmaceutical dosage
forms. Microspheres efficiently utilized in controlled delivery of many drugs but wastage of drug
due to low drug entrapment efficiency is the major drawback of such microparticulate system.
Well designed microspheres can overcome such problems by enhancing the loading efficiency of
a particular drug and minimizing the wastage of drug. It is the reliable means to increase the
loading efficiency, if optimize the formulation as well as process variables. This will only
possible by understanding the effect of various variables which affect the drug entrapment
efficiency of these microspheres. The intent of the paper is to highlight the various variables
which influence the drug entrapment efficiency along with method of preparation and
characterization of microspheres.