title: Intraocular biodistribution of intravitreal injected chitosan/gelatin nanoparticles.
abstract: The aim of this study was to evaluate intraocular biodistribution of a fluorescent polymeric nanosystem composed of chitosan and gelatin after intravitreal administration in rat eyes. The nanoparticles based on chitosan and gelatin were synthesized using a reverse emulsion-double cross-linking technique (ionic and covalent) and their structural characteristics are presented. Two units of 1% suspension of fluorescein-labeled nanoparticles in saline solution were injected intravitreal in rat eyes. The histological cross-sections obtained at 24 and 72 hours were analyzed by confocal microscopy and compared to a similar number of control cross-sections. The scanning electron microscopy of the nanoparticles obtained by double cross-linking in reverse emulsion technique revealed spherical, smooth, highly porous particles with no tendency to form aggregates. The chitosan-fluorescein conjugate was present in all the ocular tissues both at 24 and at 72 hours. The nanoparticles were present in the retina in a larger quantity and persisted longer than in the other ocular tissues. They were mainly fixed paravascular. The double cross-linking in reverse emulsion technique was efficient in synthesizing a biocompatible polymeric nanosystem. The in vivo study of intraocular biodistribution of fluorescein-labeled nanoparticles revealed their affinity for the retina after intravitreal administration.
authors.affiliation: Discipline of Anatomy and Embryology, Morphofunctional Department, "Grigore T. Popa" University of Medicine and Pharmacy, Iassy, Romania; dr_anca_sava@yahoo.com.
authors.forename: Andreea Dana
authors.initials: AD
authors.lastname: Moraru
authors.forename: Marcel
authors.initials: M
authors.lastname: Costuleanu
authors.forename: Anca
authors.initials: A
authors.lastname: Sava
authors.forename: DănuŢ
authors.initials: D
authors.lastname: Costin
authors.forename: Cătălina
authors.initials: C
authors.lastname: Peptu
authors.forename: Marcel
authors.initials: M
authors.lastname: Popa
authors.forename: Dorin
authors.initials: D
authors.lastname: Chiseliţă
mesh_terms: D000818:Animals; D002417:Cattle; D048271:Chitosan / Q000008:administration & dosage* / Q000494:pharmacology*; D005123:Eye; D005453:Fluorescence; D005780:Gelatin / Q000008:administration & dosage* / Q000494:pharmacology*; D058449:Intravitreal Injections; D053758:Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D011108:Polymers / Q000737:chemistry; D017208:Rats, Wistar; D014018:Tissue Distribution / Q000187:drug effects
chemical_list: D011108:Polymers; D005780:Gelatin; D048271:Chitosan