title: A drug-eluting contact lens.
abstract: OBJECTIVE
  To formulate and characterize a drug-eluting contact lens designed to provide extended, controlled release of a drug.
  
  
  METHODS
  Prototype contact lenses were created by coating PLGA (poly[lactic-co-glycolic acid]) films containing test compounds with pHEMA (poly[hydroxyethyl methacrylate]) by ultraviolet light polymerization. The films, containing encapsulated fluorescein or ciprofloxacin, were characterized by scanning electron microscopy. Release studies were conducted in phosphate-buffered saline at 37 degrees C with continuous shaking. Ciprofloxacin eluted from the contact lens was studied in an antimicrobial assay to verify antimicrobial effectiveness.
  
  
  RESULTS
  After a brief and minimal initial burst, the prototype contact lenses demonstrated controlled release of the molecules studied, with zero-order release kinetics under infinite sink conditions for over 4 weeks. The rate of drug release was controlled by changing either the ratio of drug to PLGA or the molecular mass of the PLGA used. Both the PLGA and the pHEMA affected release kinetics. Ciprofloxacin released from the contact lenses inhibited ciprofloxacin-sensitive Staphylococcus aureus at all time-points tested.
  
  
  CONCLUSIONS
  A prototype contact lens for sustained drug release consisting of a thin drug-PLGA film coated with pHEMA could be used as a platform for ocular drug delivery with widespread therapeutic applications.
authors.affiliation: Department of Ophthalmology, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, Massachusetts 02115, USA.
authors.forename: Joseph B
authors.initials: JB
authors.lastname: Ciolino
authors.forename: Todd R
authors.initials: TR
authors.lastname: Hoare
authors.forename: Naomi G
authors.initials: NG
authors.lastname: Iwata
authors.forename: Irmgard
authors.initials: I
authors.lastname: Behlau
authors.forename: Claes H
authors.initials: CH
authors.lastname: Dohlman
authors.forename: Robert
authors.initials: R
authors.lastname: Langer
authors.forename: Daniel S
authors.initials: DS
authors.lastname: Kohane
mesh_terms: D000890:Anti-Infective Agents / Q000008:administration & dosage*; D001672:Biocompatible Materials; D002939:Ciprofloxacin / Q000008:administration & dosage*; D003263:Contact Lenses, Hydrophilic; D016503:Drug Delivery Systems; D019793:Fluorescein / Q000008:administration & dosage*; D019344:Lactic Acid / Q000737:chemistry; D008855:Microscopy, Electron, Scanning; D011100:Polyglycolic Acid / Q000737:chemistry; D011102:Polyhydroxyethyl Methacrylate / Q000737:chemistry; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D013211:Staphylococcus aureus / Q000187:drug effects*
chemical_list: D000890:Anti-Infective Agents; D001672:Biocompatible Materials; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011102:Polyhydroxyethyl Methacrylate; D011100:Polyglycolic Acid; D019344:Lactic Acid; D002939:Ciprofloxacin; D019793:Fluorescein