title: Chitosan nanoparticles amplify the ocular hypotensive effect of cateolol in rabbits.
abstract: OBJECTIVE
  To assess the potential of chitosan (CS) nanoparticles for ocular drug delivery by investigating their intraocular retention by γ-scintigraphy and intraocular pressure reduction.
  
  
  METHODS
  Carteolol (CRT) loaded CS-NPs were prepared by ionotropic gelation method. A four-factor three-level Box-Behnken design was employed to investigate the influence of independent variables on particle size, loading capacity and entrapment efficiency. Characterization was done for particle size, encapsulation efficiency, loading capacity and in vitro drug release and transcorneal permeation, histopathology and confocal microscopy, in vitro ocular tolerance. Intraocular retention was assessed by γ-scintigraphy, and intraocular pressure was measured by tonometer betamethasone induced glaucoma rabbits.
  
  
  CONCLUSIONS
  The optimized nanoparticles showed a particle size of 243 nm (PDI - 0.304±0.04) and drug loading 49.21±2.73% with entrapment efficiency of 69.57±3.54%. In vitro release studies showed a sustained release for 24h as compared to drug solution. Ex vivo studies showed good permeation with non-significant changes in cornea anatomy indicating its safe nature. γ-Scintigraphy study showed good spread and retention (<0.05) in precorneal area as compared to the aqueous CRT solution and prolonged reduction in intraocular pressure (P<0.001).
  
  
  CONCLUSIONS
  These results indicate that CS nanoparticles are promising vehicles of CRT for ocular drug delivery.
authors: Department of Pharmaceutics, Faculty of Pharmacy, Jamia Hamdard, New Delhi 62, India.
authors: Ameeduzzafar
authors: Department of Pharmaceutics, Faculty of Pharmacy, Jamia Hamdard, New Delhi 62, India.
authors: Javed
authors: J
authors: Ali
authors: Department of Nuclear Medicine Institute of Nuclear Medicine and Allied Sciences, New Delhi, India.
authors: Aseem
authors: A
authors: Bhatnagar
authors: Department of Nuclear Medicine Institute of Nuclear Medicine and Allied Sciences, New Delhi, India.
authors: Neeraj
authors: N
authors: Kumar
authors: Department of Pharmaceutics, Faculty of Pharmacy, Jamia Hamdard, New Delhi 62, India. Electronic address: alipharm@gmail.com.
authors: Asgar
authors: A
authors: Ali
mesh_terms: D000268:Adhesiveness; D000818:Animals; D002354:Carteolol / Q000737:chemistry / Q000494:pharmacology* / Q000627:therapeutic use; D048271:Chitosan / Q000737:chemistry* / Q000378:metabolism; D003315:Cornea / Q000378:metabolism; D004337:Drug Carriers / Q000737:chemistry* / Q000378:metabolism; D005901:Glaucoma / Q000000981:diagnostic imaging / Q000188:drug therapy* / Q000473:pathology / Q000503:physiopathology*; D006873:Hydroquinones / Q000737:chemistry / Q000494:pharmacology* / Q000627:therapeutic use; D007429:Intraocular Pressure / Q000187:drug effects*; D009092:Mucous Membrane / Q000378:metabolism; D053758:Nanoparticles; D010316:Particle Size; D010539:Permeability; D011817:Rabbits; D011877:Radionuclide Imaging
chemical_list: D004337:Drug Carriers; D006873:Hydroquinones; D002354:Carteolol; D048271:Chitosan; C031927:hydroquinone
keywords: Box–Behnken; Gamma scintigraphy; Intraocular pressure