Influence of formulation parameters on encapsulation and release characteristics of curcumin loaded in chitosan-based drug delivery carriers

Drugs derived from plants with excellent chemotherapeutic effectiveness and relatively low toxicity may fail to scale through the phyto-drug discovery channel due to lack of appropriate drug delivery systems. These phytoceuticals need compatible carriers that will improve their stability, bioavailability and enhance their effectiveness. In this study, chitosan-based drug delivery carriers (DDCs) containing curcumin as phyto-drug model were prepared either via ionotropic gelation with tripolyphosphate or polyelectrolyte complexation with alginate. Influence of formulation parameters was evaluated using encapsulation and release characteristics as response indices. Crosslinking time, pH of chitosan solution and concentration of curcumin, alginate or tripolyphosphate significantly influenced the encapsulation efficiency, rate of curcumin release and mean release time (MRT) in simulated gastric fluid (SGF). Roughly spherical chitosan-based micro-beads with copious pores within the matrix and of improved encapsulation efficiency (82–93%) were prepared using optimized set of formulation parameters. Incorporation of alginate into the chitosan DDC reduced erosion of curcumin by 30% and extended MRT by 180 min in SGF without net delineating change in release profiles of curcumin in simulated physiological saline and intestinal fluids. Time-dependent in vitro study showed that radical scavenging activity ratio of curcumin was enhanced via encapsulation in chitosan-based DDCs.