Colon specific chitosan microspheres for chronotherapy of chronic stable angina

▶ Discrete, spherical Eudragit S-100 coated chitosan microspheres were successfully prepared. ▶ Microspheres depicted appropriate release patterns in simulated GI fluids. ▶ Enhanced release characteristics in the presence of colonic microflora. ▶ Eudragit S-100 proved to be effective in preventing a premature release of diltiazem in upper GIT. ▶ Chitosan ensured a controlled release of drug in the colon.