title: Chitosan-based hydrogels for nasal drug delivery: from inserts to nanoparticles.
abstract: BACKGROUND
  Chitosan represents a multifunctional polymer, featuring both mucoadhesive and permeation-enhancing properties and therefore is a widely studied excipient for mucosal drug delivery. As regards nasal administration, chitosans have been used for the preparation of gels, solid inserts, powders and nanoparticles in which a three-dimensional network can be recognized.
  
  
  METHODS
  This review provides a discussion of the different nasal dosage forms based on chitosan hydrogels. In the first section intranasal delivery is discuss as a useful tool for non-invasive administration of drugs intended for local or systemic treatments. Then chitosan-based hydrogels are described with a focus on their mucoadhesive and permeation-enhancing ability as well as their capacity of controlled drug release. Finally, a detailed discussion regarding several examples of the different nasal dosage forms is reported, including considerations on in vitro, ex vivo and in vivo studies.
  
  
  RESULTS
  Summary and discussion of recent data on the different pharmaceutical forms based on chitosan hydrogels could be of interest to researchers dealing with nasal drug delivery.
  
  
  CONCLUSIONS
  The aim of this review is to stimulate further investigations in order to achieve the collection of harmonized data and concrete clinical perspectives.
authors.affiliation: Bologna University, Faculty of Pharmacy, Via S Donato 19/2, 40127 Bologna, Italy. barbara.luppi@unibo.it
authors.forename: Barbara
authors.initials: B
authors.lastname: Luppi
authors.forename: Federica
authors.initials: F
authors.lastname: Bigucci
authors.forename: Teresa
authors.initials: T
authors.lastname: Cerchiara
authors.forename: Vittorio
authors.initials: V
authors.lastname: Zecchi
mesh_terms: D000281:Administration, Intranasal; D048271:Chitosan / Q000737:chemistry; D004304:Dosage Forms; D004337:Drug Carriers; D020100:Hydrogels; D015394:Molecular Structure; D008970:Molecular Weight; D053758:Nanoparticles
chemical_list: D004304:Dosage Forms; D004337:Drug Carriers; D020100:Hydrogels; D048271:Chitosan