FORMULATION AND EVALUATION OF COLON TARGETED CURCUMIN MICROSPHERES USING NATURAL POLYMERS

Abstract

Curcumin is used to treat colon cancer, but it has very poor absorption in upper part of GIT. As a part of drug delivery, colon offers near neutral pH, reduced digestive enzymetic activity, a long transit time and increased responsiveness to absorption enhancers. The aim of present study is to identify suitable polymer (guar gum or xanthan gum) based microspheres promising in-vitro mouth-to-colon release profile. Curcumin loaded microspheres were prepared by ionic cross linking technique using calcium chloride. Three formulations with each polymer (sodium alginate: guar gum / sodium alginate: xanthan gum) using different concentrations were formulated by ionic cross linking technique. Microspheres were subjected to evaluation by studying parameters like percentage yield, particle size, IR spectroscopy, TLC, SEM, percentage entrapment efficiency and in-vitro release profile. In-vitro drug release study was performed using simulated gastric fluid and simulated intestinal fliud for 8 hrs. Natural or modified polysaccharides (guar gum, xanthan gum, locust gum, dextrans, starch, amylose, pectins) degraded by the human colonic flora, have thus been investigated as colonic drug delivery carriers. 0.75 percent polymer containing formulation showed retarded release at the end of 8 hrs. All the batches in first two hours showed very negligible release, then it showed increase in drug release up to 8 hours. Xanthan gum microspheres showed more retarded release than guar gum microspheres. The microspheres are spherical in shape and having rough surface.