Advances in Colon-targeted Drug Delivery Systems: Innovative Strategies for Treating Colonic Disorders and Prospects for the Future

Colon-specific targeting delivery systems have drawn a great deal of attention because they represent potential vehicles for treating colonic disorders like diverticulitis, colitis, salmonellosis, Crohn's disease, etc. with less systemic adverse effects as well as for the better oral delivery of many therapeutics that are prone to enzymatic and acidic deterioration in the upper GI tract. Smart polymeric delivery systems in particular have been investigated as "intelligent" delivery systems capable of releasing entrapped pharmaceuticals at the proper time & site of action in response to certain physiological stimuli. The creation of novel polymers & crosslinkers with improved biodegradability and biocompatibility would expand and enhance applications now in use. The development of polymeric systems could result in more precise and programmable drug delivery/therapies. In addition, newer advancements have led to the development of numerous ground-breaking techniques for directing a medication molecule to the colon. This review highlighted formulation techniques pH-dependent, time-dependent, enzyme sensitive, magnetically dependent, ligand-receptor mediated, and microflora-activated systems. Moreover, several methods have been put forth that make use of the innovative idea of such delivery systems, and mechanisms in which the release of drugs is regulated by pH and time as well as pH and the colon's bacteria.