Formulation, Optimization, and in vitro Characterization of Curcumin Loaded Liposomes for Colonic Delivery

Background: Curcumin has been extensively employed in the treatment of several diseases in traditional medicine, including cancer.The main obstacles that avert its approval as a therapeutic moiety are its low aqueous solubility and low in vivo bioavailability. Liposomes have been recognized as effective carrier systems owing to their ability to solubilize hydrophobic molecules and to change their pharmacokinetic attributes. This study was intended at developing Eudragit S 100 coated alginate beads bearing curcumin loaded liposomes for colonic delivery. Methods: The liposomes were prepared by the film casting method. The optimization of various formulation and process variables was done by Box-Behnken design using DesignExpert® Software.Three variables i.e.HSPC:Chol molar ratio (X1 ),curcumin concentration (X2 ),and sonication time (X3 ) were selected as independent variables and entrapment efficiency of curcumin, polydispersity index, and vesicle size were selected as dependent variables. Results: The optimized liposomes had an average particle size of 109. 8 ± 1.4 nm, polydispersity index 0.218 ± 1.2, zeta potential +19.30 ± 2.46 mV, and with entrapment efficiency 70.16 ± 1.6 %. These liposomes were entrapped in eudragit coated beads and these beads were characterized for their size, swelling index and in vitro drug release.The in vitro drug release depicted that no release was observed till 6 hrs and a sustained and significant drug release was noted after 6.5 hr. Conclusion: The stability studies indicated that liposomes were stable at 4°C depicting little aggregation of the vesicles. The research suggested that curcumin-loaded liposomes bearing eudragit coated calcium alginate beads can be effectively used for colonic delivery.