title: Design of eudragit RL nanoparticles by nanoemulsion method as carriers for ophthalmic drug delivery of ketotifen fumarate.
abstract: OBJECTIVE
  Ketotifen fumarate (KF) is a selective and noncompetitive histamine antagonist (H1-receptor) that is used topically in the treatment of allergic conditions of rhinitis and conjunctivitis. The aim of this study was to formulate and improve an ophthalmic delivery system of KF. Ocular nanoparticles were prepared with the objective of reducing the frequency of administration and obtaining controlled release to improve the anti-inflammatory drug delivery.
  
  
  METHODS
  In the present study, ocular KF loaded Eudragit RL 100 nanoparticles were prepared using O/W solvent diffusion method. The nanoparticles were evaluated for particle size, entrapment efficiency, surface morphology, X-ray diffraction (XRD), Fourier transform spectroscopy (FTIR), and differential scanning calorimetry (DSC). In vitro release and permeation studies were also carried out on nanoparticles.
  
  
  RESULTS
  An average size range of 182 to 314.30 nm in diameter was obtained and encapsulation efficiency up to 95.0% was observed for all the formulations. Drug release for all formulations after 24 hr was between 65.51% and 88.82% indicating effective controlled release property of KF. The mechanism of drug release for best formulation was found to be fickian diffusion mechanism. KF nanoparticles containing high polymer concentration (1:15) presented a faster drug release and a higher drug penetration; on the contrary, nanoparticles containing low polymer concentration (1:7.5) were able to give a more sustained release of the drug and thus a slower KF permeation through the cornea.
  
  
  CONCLUSIONS
  The study revealed that KF NPs were capable of releasing the drug for a prolonged period of time and increasing the ocular bioavailability.
authors.affiliation: Drug Applied Research Center, Tabriz University of Medical Sciences, Tabriz, Iran; Student Research Committee, Tabriz University of Medical Sciences, Tabriz, Iran.
authors.forename: Saieede
authors.initials: S
authors.lastname: Soltani
authors.affiliation: Liver and Gastrointestinal Diseases Research Center, Tabriz University of Medical Sciences, Tabriz, Iran; Department of Pharmaceutics, Faculty of Pharmacy, Tabriz University of Medical Sciences, Tabriz, Iran.
authors.forename: Parvin
authors.initials: P
authors.lastname: Zakeri-Milani
authors.affiliation: Department of Pharmaceutics, Faculty of Pharmacy, Tabriz University of Medical Sciences, Tabriz, Iran.
authors.forename: Mohammad
authors.initials: M
authors.lastname: Barzegar-Jalali
authors.affiliation: Drug Applied Research Center, Tabriz University of Medical Sciences, Tabriz, Iran; Department of Pharmaceutics, Faculty of Pharmacy, Tabriz University of Medical Sciences, Tabriz, Iran.
authors.forename: Mitra
authors.initials: M
authors.lastname: Jelvehgari
keywords: Eudragit RL 100; Ketotifen fumarate; Nanoparticle; Ocular