FORMULATION AND INVITRO EVALUATION OF METRONIDAZOLE TABLETS FOR COLON TARGETTED DRUG DELIVERY SYSTEM Yalla Karunakar Reddy1 , G. S.Valluri2 , K. Kishore3 , Dr.G.Vijaya Kumar*

In the present research work sustained release matrix formulation of Metronidazole targeted to colon by using various polymers developed. To achieve pH-independent drug release of Metronidazole, pH modifying agents (buffering agents) were used. Colon targeted tablets were prepared in two steps. Initially core tablets were prepared and then the tablets were coated by using different pH dependent polymers. Ethyl cellulose, Eudragit L100 and S100 were used as enteric coating polymers. The precompression blend of all formulations was subjected to various flow property tests and all the formulations were passed the tests. The tablets were coated by using polymers and the coated tablets were subjected to various evaluation techniques. The tablets were passed all the tests. Among all the formulations F3 formulation was found to be optimized as it was retarded the drug release up to 12 hours and showed maximum of 98.69% drug release. It followed zero order kinetics mechanism. Key Words: Metronidazole, Colon targeted tablets.