title: Development of Ocular Delivery System for Glaucoma Therapy Using Natural Hydrogel as Film Forming Agent and Release Modifier.
abstract: BACKGROUND
  Glaucoma is characterized by increased intraocular pressure, which results in damage to the optic nerve. The existing therapy with conventional eye drops is inefficient due to nasolachrymal drainage, resulting in a reduced corneal residence of the drug.
  
  
  OBJECTIVE
  The objective was to develop controlled-release ocular films of timolol maleate using natural hydrogel from Tamarindus indica seeds as a sustaining and film-forming agent, to overcome the problems associated with eye drops.
  
  
  METHODS
  The hydrogel was isolated using hot aqueous extraction followed by precipitation with ethanol. Six batches of ocular films were prepared and evaluated for drug content, weight variation, thickness, diameter and in vitro release profile. The ideal batch of the films was subjected to stability, pharmacodynamic and ocular safety studies.
  
  
  RESULTS
  The yield of the hydrogel was 58.29%. The thickness of the ocular films was in the range of 0.17 to 0.25 mm and the weight of the films was found to increase with the increase in polymer content. The drug release from the films was found to be controlled over a period of 8 h. The films were found to be stable and were able to reduce the intraocular pressure for 24 h in a more efficient manner than the eye drops. The films were found to be practically non-irritating to the eye.
  
  
  CONCLUSIONS
  It can be concluded that the hydrogel from tamarind seeds can be used as a film-forming and release-controlling agent for the development of an ocular drug delivery system for the effective therapy of glaucoma.
authors.affiliation: Amity Institute of Pharmacy, Amity University, Noida, Uttar Pradesh, India.
authors.forename: Giriraj T
authors.initials: GT
authors.lastname: Kulkarni
authors.affiliation: Meerut Institute of Engineering and Technology, Meerut, Uttar Pradesh, India.
authors.forename: Nitin
authors.initials: N
authors.lastname: Sethi
authors.affiliation: Laureate Institute of Pharmacy, Kathog, Kangra Dist., Himachal Pradesh, India.
authors.forename: Rajendra
authors.initials: R
authors.lastname: Awasthi
authors.affiliation: CSIR - Central Drug Research Institute, Lucknow, Uttar Pradesh, India.
authors.forename: Vivek Kumar
authors.initials: VK
authors.lastname: Pawar
authors.affiliation: Meerut Institute of Engineering and Technology, Meerut, Uttar Pradesh, India.
authors.forename: Vineet
authors.initials: V
authors.lastname: Pahuja
mesh_terms: D000818:Animals; D003692:Delayed-Action Preparations; D005123:Eye / Q000187:drug effects* / Q000503:physiopathology; D005260:Female; D005901:Glaucoma / Q000188:drug therapy* / Q000503:physiopathology; D020100:Hydrogels; D007429:Intraocular Pressure / Q000187:drug effects; D008297:Male; D011817:Rabbits; D012639:Seeds / Q000737:chemistry; D029861:Tamarindus / Q000737:chemistry; D013999:Timolol / Q000008:administration & dosage* / Q000627:therapeutic use; D016896:Treatment Outcome
chemical_list: D003692:Delayed-Action Preparations; D020100:Hydrogels; D013999:Timolol
keywords: ocular safety; pharmacodynamics; polysaccharide; tamarind seed; timolol maleate