The Use of Natural Polymers in Formation of Polyelectrolyte Complexation

In recent years, great advances have been made towards the development of various techniques for novel drug delivery systems. These techniques focus on the rate of drug delivery, duration of action and site of action. One of such technique in fabricating novel drug delivery system is the use of polymers in development of in-situ drug delivery systems. Polymers used as carriers have revolutionized over the years. The formation of a polymer complex with other oppositely charged polymers resulted in the formation of polyelectrolyte complexes, which possess unique physicochemical properties with high biocompatibility. The polyelectrolyte's themselves are characterized as cationic, anionic and non-ionic according to the nature of the functional group present at the polymer chain, type of macromolecules formed and interaction forces existing between the complex formed. Additionally, these natural complexes avoid the use of chemical agents for cross linking of polymeric chains, thereby limiting toxicity. Due to their sustain and convenient way to deliver highly water soluble drugs they could target therapeutically active moiety to the site of action, and for these reasons they have led to various applications in the biomedical sector, in pharmaceutical and nano biotechnology industries. Thereby the use of polymers in in-situ drug delivery offers many benefits because of their sustained and prolonged drug delivery action when compared with other conventional drug delivery systems. The present review focuses on the use of natural Polymers in polyelectrolyte complexes as a drug delivery technology.