Applications of Chitosan Microspheres as Drug Delivery Vehicles

Abstract

The main goal of pharmacotherapy for any condition is to achieve and maintain the intended curative quantity of the therapeutic agent in the bloodstream or at the desired site during the whole course of treatment. Conventional drug dosage forms frequently cause inescapable changes in drug concentration, which have the negative effects of insufficient or excessive dose, frequent administration, and poor patient adherence. In this regard, various medication delivery and targeting methods are being developed to address these issues and improve overall drug bioavailability. Polymers, micelles, microcapsules, liposomes, and lipoproteins are a few examples of such drug carrier systems. The delivery of drugs is affected differently by each polymer carrier. Typically, synthetic polymers are expensive, persistent, and non-bio-compatible. Natural polymers like chitin and chitosan do not present these problems. A naturally occurring polymer called chitosan (CS) is frequently used in medicinal applications because of its affordability, biodegradability, biocompatibility, non-toxic makeup, and capacity to cling to mucosal surfaces. Because of its cationic characteristics , CS can interact with polyanions to produce polyelectrolyte complexes. CS has thus shown to be particularly useful in improving the dissolving of insoluble medicines and in multiparticulate drug delivery. Chitosan has emerged as a prospective natural polymer for the formulation of microspheres and microcapsules. Ionotropic gelation, spray drying, emulsion phase separation, simple coacervation, and complex coacervation are some of the techniques used in chitosan microencapsulation. This chapter will primarily concentrate on the synthesis and characterization of chitosan microspheres, as well as their use in novel drug delivery systems.