Chapter 9 - Ionotropically gelled alginate particles in sustained drug release

Abstract

Since the past few decades, the preparation of polymeric particles as multiple-unit sustained drug releasing carriers like beads, microparticles, and nanoparticles, via the ionotropic gelation technique, is being expanded as a fashionable biopolymer research, especially in the biomedical areas including drug delivery applications. Ionotropically gelled different biopolymeric particles are synthesized employing one or more than one ionic natured polymer(s). Most of the reported ionotropically gelled drug releasing systems was composed of anioinic polymers like sodium alginate, low methoxy pectin, gellan gum, and sodium carboxymethyl cellulose and cationic polymer like chitosan. Among these, alginates have extensively utilized for the preparation of biopolymeric beads, microparticles, nanoparticles, etc. via the ionotropic gelation employing various trivalent as well as divalent metal cations (e.g., Al3+, Fe3+, Ca2+, Cu2+, Zn2+, Cd2+, Ba2+, Pb2+). A variety of drug candidates have successfully been encapsulated within ionotropically gelled alginate-based particles and thereby, these drug encapsulated particles have been demonstrated diverse profiles of drug releasing in sustained manner over a longer period. The current chapter deals with a useful discussion on various ionotropically gelled alginate-based particles for sustained drug releasing.