Chitosan and Its Microparticles as Carriers in Drug Delivery Systems: An Overview

The development of a new drug molecule is an expensive and time consuming effort. Improving the safety efficacy ratio of old drugs has been attempted by different methods focused on each individual drug therapy, dose specification and therapeutic drug monitoring. Controlled rate delivery, slow delivery and targeted delivery are other very promising methods which have been pursued intensively. Methods for increasing bioavailability, diminishing side-effects, promoting targeted delivery and treating conditions such as blood-brain barrier disorders, are the main topics in novel drug delivery explorations. Choosing a suitable polymer is one of the most important aspects in development of a drug delivery system. In the last three decades, avast number of biomedical applications have been reported for a chitin derivative, known as chitosan. In this overview the properties of this polymer, as a natural compound, which are the main criteria for its extensive application in different areas of biomedicine are described, specifically in relation to synthesis of chitosan microparticles applied in novel drug delivery.