Role of regional absorption and gastrointestinal motility on variability in oral absorption of a model drug

Orally Administrated Olsalazine-Loaded Multilayer Pectin/Chitosan/Alginate Composite Microspheres for Ulcerative Colitis Treatment

“…Compared with enema, oral administration with non-invasive and higher convenience is a preferred choice in chronic gastrointestinal diseases. , However, as the colon is located at the end of the digestive tract, the drug has to undergo gastric acid breakdown and enzyme degradation secreted by the small intestinal flora to reach the colon. − In addition, the rapid removal of drug caused by diarrhea and the massive absorption caused by systematic exposure diminish the drug bioavailability . Thus, it is particularly vital to manufacture a drug carrier for colitis that can shrink in stomach acid and avoid degradation by intestinal flora. ,, …”

Fabrication of gelatin Bi2S3 capsules as a highly sensitive X-ray contrast agent for gastrointestinal motility assessment in vivo

“…16 The use of the rst radiopaque agent most likely dates back to 1896, when BaSO 4 was used to study gastrointestinal motility of animals 17 and various morphologies of BaSO 4 agents have been developed to meet the requirement of different diseases during the past decades. [18][19][20][21] Currently, for gastrointestinal motility assessment in clinic, the patients orally take 2 capsules (containing 20 BaSO 4 rods) aer breakfast on the day of examination. Then the whole gut transit time was evaluated through observing the change of the position and the number of BaSO 4 rods at different time points by Xray imaging.…”