title: Topical drug delivery using chitosan nano- and microparticles.
abstract: BACKGROUND
  Topical drug delivery offers important benefits for improving the therapeutic effect and reducing systemic side effects of the administered compounds. In addition, utilization of biopolymeric material-based systems can play a key role in developing new topical dosage forms and their applications. This review describes the advances that have been made, new strategies and as well as possible challenges of particular systems of chitosan used in topical drug delivery, including challenging innovations in topical usage of these systems that can make significant impact on clinical practice.
  
  
  METHODS
  The main area covered is hypothesis that particulate carriers based on chitosan and its derivatives can penetrate the topical barriers from the body. For this reason, the novel studies described emphasize the fact that chitosan-based particular systems are popular that can be tailor-made according to in vitro and in vivo characterization. Such parameters, which are known to influence their in vivo performance, can be modulated by adjusting the formulation conditions of the chitosan-based particular systems for topical application.
  
  
  CONCLUSIONS
  The topical application of drugs with particulate systems comprising a natural polymer, chitosan, is one of the most popular drug delivery routes. The aim of topical use of chitosan particles is to improve the drug bioavailability by prolonging the residence time of drugs applied topically or by enhancing the passing of drugs through the epithelial cells by opening the tight junctions between epithelial cells and also to reduce the side effects of the drugs.
authors: Marmara University, Faculty of Pharmacy, Department of Pharmaceutical Biotechnology, 34668, Istanbul, Turkey. adsezer@marmara.edu.tr
authors: Ali Demir
authors: AD
authors: Sezer
authors: Erdal
authors: E
authors: Cevher
mesh_terms: D000287:Administration, Topical; D000818:Animals; D001672:Biocompatible Materials / Q000008:administration & dosage*; D001682:Biological Availability; D002626:Chemistry, Pharmaceutical; D048271:Chitosan / Q000008:administration & dosage*; D016503:Drug Delivery Systems; D006801:Humans; D053758:Nanoparticles
chemical_list: D001672:Biocompatible Materials; D048271:Chitosan