Conventional and novel approaches for colon specific drug delivery: a review

Abstract

Lot of research is undergoing in colon specific drug delivery as this drug delivery route is not only useful for targeting the drugs required in the treatment of diseases associated with colon, but also as a potential site for the local and systemic delivery of peptide and proteins and other therapeutic drugs. Precise colon drug delivery requires the triggering mechanism in the delivery system that can respond only to the physiological conditions specific to the colon. The primary conventional approaches used to obtain colon-specific delivery were based on prodrugs, pH and timedependent systems or microflora activated systems and achieved limited success. However, recently continuous efforts have been taken on designing colon-specific delivery systems with improved site specificity and versatile drug release kinetics to accomplish different therapeutic needs. The focus of this review is to provide detailed insight into the conventional as well as recent approaches used to target the therapeutic agents specifically to the colon