Preparation and Characterization of Curcumin and Epigallocatechin gallate co-loaded polymeric microspheres for Colonic delivery

Abstract

Curcumin (CURC) is a natural polyphenolic compound obtained from Curcuma longa which shows preventive and therapeutic actions against cancer. Epigallocatechin gallate (EGCG) is a potent phytomolecule obtained from Camellia sinensis, with wide biological activity. The therapeutic effect is limited, owing to poor stability and limited membrane permeability across the intestine. The aim of this study was to develop and evaluate colon-targeted microspheres of CURC and EGCG, using natural polymers. W/O emulsion crosslinking technique was used to prepare microspheres of CURC and EGCG using interpenetrating network (IPN) of Chitosan (CS) and Gum acacia (GA) and glutaraldehyde was used as a crosslinking agent. Prepared microspheres were filled in capsules coated with Eudragit S100. The prepared microspheres were evaluated in vitro for preformulation studies, encapsulation efficiency, micromeritic properties, dissolution studies and stability studies. FTIR and DSC studies had proved that the drug and polymers are compatible. The good flow property of microspheres showed that the microspheres are not aggregated. SEM micrographs of microspheres show a rough and folded surface morphology. The microspheres are spherical and uniform in shape. Formulations showed good encapsulation efficiency. Formulation F1 to F6 showed sustained release of drug for 10 h. The in-vitro drug release of batches was best explained by Higuchi models showing anomalous diffusion mechanism. The coated batch showed better release results. The optimized formulation for a period of 3 month at 40±2°/75 ± 5% RH showed no significant changes. The current approach was helpful to develop polysaccharide based microspheres of CURC and EGCG to enhance colonic drug delivery.