FORMULATION AND EVALUATION OF COLON TARGETED DRUG DELIVERY SYSTEM OF BUSULFAN: USING COMBINATION OF pH AND TIME DEPENDANT SYSTEMS

In present work Colon targeting drug delivery system was developed for Busulfan an anticancer drug by using combination of delayed systems one is pH dependant and other is time dependant delayed system. Rapid release core tablet (RRCT) formulations were prepared using Busulfan drug with different disintegrating agents in different concentrations. The pre-compression and post-compression parameters of all formulations were determined and the values were found to be satisfactory. From the In-vitro dissolution studies, F6 formulation with 12% Hydroxy propyl cellulose (HPC) was the best formulation. For optimized RRCT formulation press coat was done by using Xanthum Gum and Ethyl Cellulose (EC) in different ratios. Press coated tablet delays the drug release up to 8 hours based on the nature and concentrations of the polymer. Each press coated tablet was coated using enteric solution made of HPMC phthalate, Myvacet and color dissolved in ethanol. Enteric press coated tablets (EPCT) were delayed drug release up to 2hrs in fed condition due to pH dependant delayed system. Based on dissolution studies of EPCT formulations, C3OPF formulation was optimized and showed delayed release pattern in a much customized manner. As a result of this study it may be concluded that the colon targeted drug delivery tablets using a combination of two polymers in optimized concentrations can be used to increase the delayed action of drug release to deliver the drug in a delayed manner. Key words: Colon, RRCT, HPC, Xanthum gum and EPCT