title: Preparation and characterization of nanocapsules for colon-targeted drug delivery system.
abstract: BACKGROUND
  Nanoparticles for colon-specific drug delivery system are known for their specific accumulation in the inflamed tissue in the colon and may therefore allow a selective delivery to the site of inflammation for the treatment of inflammatory bowel disease (IBD).
  
  
  OBJECTIVE
  The objective of this study was to formulate and evaluate nanocapsules (NC), an oral system designed to achieve site-specific and instant drug release in colon for effective treatment of IBD.
  
  
  METHODS
  Prednisolone (PD), a typical glucocorticoid, has been widely used for the treatment of IBD. In this study, nanoprecipitation method was used to prepare polymeric NC of PD with pH responsive polymer Eudragit S100. The effect of several formulation variables such as surfactant, oil, and polymer on the PD-NC properties (average size, drug release rate, and drug entrapment) was investigated. In vitro drug release study was done by changing pH method and an in vivo study on rat was done to ascertain efficiency of PD-NC to release drug specifically in colon.
  
  
  CONCLUSIONS
  The optimized formulations lead to the preparation of PD-NC with a mean size of 567.87 nm, high encapsulation efficiency of 90.21%. In vitro studies reveal that NC releases the drug after 4.5-h lag time corresponding to time to reach colonic region, and in vivo studies show that NC release drug after 3-h lag time in rat corresponds to arrival in colon.
  
  
  CONCLUSIONS
  The above NC formulation of PD is the targeted drug to the colon and may provide effective way of treatment of colonic disease.
authors.affiliation: Department of Pharmaceutics, AISSMS College of Pharmacy, Pune, Maharashtra, India. sanjayjk@rediffmail.com
authors.forename: Sanjay J
authors.initials: SJ
authors.lastname: Kshirsagar
authors.forename: Mangesh R
authors.initials: MR
authors.lastname: Bhalekar
authors.forename: Jiten N
authors.initials: JN
authors.lastname: Patel
authors.forename: Santosh K
authors.initials: SK
authors.lastname: Mohapatra
authors.forename: Nitin S
authors.initials: NS
authors.lastname: Shewale
mesh_terms: D000818:Animals; D003106:Colon / Q000187:drug effects / Q000378:metabolism*; D016503:Drug Delivery Systems / Q000379:methods*; D005938:Glucocorticoids / Q000008:administration & dosage* / Q000737:chemistry / Q000493:pharmacokinetics; D015212:Inflammatory Bowel Diseases / Q000188:drug therapy; D053769:Nanocapsules / Q000737:chemistry* / Q000648:ultrastructure; D010316:Particle Size; D011109:Polymethacrylic Acids / Q000737:chemistry; D011239:Prednisolone / Q000008:administration & dosage* / Q000737:chemistry / Q000493:pharmacokinetics; D051381:Rats; D017208:Rats, Wistar; D012995:Solubility; D013501:Surface-Active Agents / Q000737:chemistry
chemical_list: D005938:Glucocorticoids; D053769:Nanocapsules; D011109:Polymethacrylic Acids; D013501:Surface-Active Agents; C038300:methylmethacrylate-methacrylic acid copolymer; D011239:Prednisolone