title: The counterbalanced effect of size and surface properties of chitosan-coated poly(isobutylcyanoacrylate) nanoparticles on mucoadhesion due to pluronic F68 addition.
abstract: OBJECTIVE
  To evaluate of the effect of size and surface characteristics of poly(isobutylcyanoacrylate) nanoparticles coated with pluronic F68 and thiolated chitosan on mucoadhesion.
  
  
  METHODS
  Nanoparticles were obtained by radical emulsion polymerization in presence of different amounts of F68 (0-4%w/v). Mucoadhesion was ex vivo evaluated by applying nanoparticle suspension on rat intestinal mucosa and quantifying the amount of attached nanoparticles after incubation.
  
  
  RESULTS
  F68 unimers added in the polymerization medium allowed decreasing nanoparticle size from 251 to 83 nm, but resulted in nanoparticle surface modification. The amount of thiolated chitosan onto nanoparticle surface was decreased resulting in lower thiol groups and zeta potential. Consequently, the decrease of nanoparticle hydrodynamic diameter resulted in eight-fold-increase of the number of nanoparticles attached to the mucosa but a significant decrease of the weight of attached nanoparticles was observed. This unexpected result was due to a decrease of the amount of chitosan and thiolated chitosan available to interact with mucus upon addition of F68 in the polymerization medium.
  
  
  CONCLUSIONS
  Addition of F68 should not be recommended to improve the amount of mucoadherent nanoparticles. Further studies could allow understanding if the low amount of small size nanoparticles could be able to improve oral bioavailability.
authors.affiliation: Université Paris-Sud, UMR CNRS 8612, Faculté de Pharmacie, 5, Rue J.B. Clément, 92296, Châtenay-Malabry, France.
authors.forename: Bénédicte
authors.initials: B
authors.lastname: Petit
authors.forename: Kawthar
authors.initials: K
authors.lastname: Bouchemal
authors.forename: Christine
authors.initials: C
authors.lastname: Vauthier
authors.forename: Madeleine
authors.initials: M
authors.lastname: Djabourov
authors.forename: Gilles
authors.initials: G
authors.lastname: Ponchel
mesh_terms: D000818:Animals; D002015:Bucrylate / Q000737:chemistry* / Q000494:pharmacology*; D048271:Chitosan / Q000737:chemistry*; D004655:Emulsions / Q000737:chemistry / Q000494:pharmacology; D007413:Intestinal Mucosa / Q000187:drug effects* / Q000378:metabolism; D008297:Male; D008855:Microscopy, Electron, Scanning / Q000379:methods; D053758:Nanoparticles / Q000737:chemistry*; D010316:Particle Size; D020442:Poloxamer / Q000737:chemistry* / Q000494:pharmacology*; D058105:Polymerization; D051381:Rats; D017208:Rats, Wistar; D013499:Surface Properties; D013501:Surface-Active Agents / Q000737:chemistry / Q000494:pharmacology; D014014:Tissue Adhesives / Q000737:chemistry / Q000494:pharmacology
chemical_list: D004655:Emulsions; D013501:Surface-Active Agents; D014014:Tissue Adhesives; D020442:Poloxamer; D002015:Bucrylate; D048271:Chitosan