Oral nanotechnological approaches for colon-specific drug delivery

This chapter discusses the main anatomophysiological challenges faced by orally administered delivery systems, and presents the colon anatomophysiological features and their influence on the advantages and limitations of colon delivery. It reviews the different parameters involved in colon-specific drug delivery by nanoparticles (NPs) and describes the different nanotechnological approaches and their application in specific health problems. The chapter provides the most common strategies for colon-specific drug delivery, namely by means of pH-sensitive polymer NPs, microbial-triggered-release NPs, and time-controlled-drug-release NPs. Generally, the drug candidates for colon-specific delivery are those intended to have local therapeutic effect, such as in the case of inflammatory bowel disease, colon cancer, irritable bowel syndrome, colonic dysmotility, parasitic diseases, diverticulitis, and diarrhea. NP-based drug delivery systems are useful tools to overcome problems, avoiding or minimizing the release of drug in the stomach and small intestine and targeting the drug release at the colon.