title: Feasibility of capsule endoscopy for direct imaging of drug delivery systems in the fasted upper-gastrointestinal tract.
abstract: OBJECTIVE
  To develop a minimally-invasive method for direct visualization of drug delivery systems in the human stomach and to compare the obtained results with an established in vitro model. The method should provide the capsule rupture, dispersion characteristics, and knowledge regarding the surrounding physiological environment in the stomach.
  
  
  METHODS
  A capsule endoscopic method was developed. The disintegration time, dispersion characteristics and the impact of the physiological environment on different lipid based delivery systems in different gelatin capsules in the fasted stomach of nine healthy volunteers were visualized. Biorelevant dissolution studies using a USP II apparatus and a droplet size analysis of the released SNEDDS were performed.
  
  
  RESULTS
  Visualization of the behavior of both hard and soft gelatin capsules formulations was possible. The disintegration and dispersion of EP oil in a soft capsule and SNEDDS in a hard shell capsule were visualized. The in vitro release rates were different from the in vivo release rates of the soft capsule due to volume, fluid composition and motility differences but not for the hard capsule containing SNEDDS.
  
  
  CONCLUSIONS
  A minimally-invasive capsule endoscopic method was developed for direct visualizing of drug delivery systems in the human stomach and maybe later, in the duodenum.
authors.affiliation: Department of Pharmacy, University of Copenhagen, Copenhagen, Denmark.
authors.forename: Pernille Barbre
authors.initials: PB
authors.lastname: Pedersen
authors.forename: Daniel
authors.initials: D
authors.lastname: Bar-Shalom
authors.forename: Stefania
authors.initials: S
authors.lastname: Baldursdottir
authors.forename: Peter
authors.initials: P
authors.lastname: Vilmann
authors.forename: Anette
authors.initials: A
authors.lastname: Müllertz
mesh_terms: D000284:Administration, Oral; D000328:Adult; D053704:Capsule Endoscopy / Q000379:methods*; D002214:Capsules; D016503:Drug Delivery Systems / Q000379:methods*; D005215:Fasting / Q000378:metabolism*; D005240:Feasibility Studies; D005260:Female; D006801:Humans; D008041:Linoleic Acids / Q000008:administration & dosage / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D031665:Oenothera biennis; D010938:Plant Oils / Q000008:administration & dosage / Q000378:metabolism*; D041742:Upper Gastrointestinal Tract / Q000187:drug effects / Q000378:metabolism*; D055815:Young Adult; D017965:gamma-Linolenic Acid / Q000008:administration & dosage / Q000378:metabolism*
chemical_list: D002214:Capsules; D008041:Linoleic Acids; D010938:Plant Oils; C028498:evening primrose oil; D017965:gamma-Linolenic Acid