Oral Nano-Delivery Systems for Colon Targeting Therapy

Background: Targeting drug delivery is an attractive research area, as it enables localized treatment, improves the efficacy of therapeutics and reduces systemic toxicity. Colon targeting delivery is particularly beneficial to the treatment of colon diseases, such as inflammatory bowel disease and colon cancer, due to the improved local drug concentrations. The traditional strategies for colon targeting delivery include time-dependent and pH-dependent technologies, etc. In recent years, nanotechnology has emerged as a novel and efficient tool for targeting drug delivery. After oral administration, nano-based formulations are able to protect drug from the harsh gastrointestinal environment and selectively increase the drug concentration at the disease site. Various orally administered drug-loaded nano-systems for colon targeting delivery have been well documented and shown great potentials in colon disease therapy. Objective: In this work, we aim to provide a comprehensive understanding of the recent progress in the area of colon targeting delivery in combination with introduction of the pathophysiological changes of diseased colon sites and the obstacles for drug delivery.