Design, development and optimization of colon targeted drug delivery system for Crohnís disease

Abstract

The aim of the present investigation was to develop double coated systems comprising of pH independent (EudragitÆ RS 100) and pH dependent coatings (EudragitÆ S 100) of polymethacrylates for delivery of metronidazole exclusively to the colon. The central composite design was used to optimize independent variables X1 (coating level of EudragitÆ RS 100) and X2 (coating level of EudragitÆ S 100) and study their effect on dependent variables Y300 (% drug released in the 5th h) and Y480 (% drug released in the 8th h). The results of interactive statistical second order model revealed that lower levels of X1 and higher levels of X2 favor the preparation of colon targeted tablets.