title: In vitro and in vivo evaluation of novel ciprofloxacin-releasing silicone hydrogel contact lenses.
abstract: OBJECTIVE
  The purpose of this study was to evaluate ciprofloxacin-releasing silicone hydrogel contact lens materials in vitro and in vivo for the treatment of microbial keratitis.
  
  
  METHODS
  Model silicone hydrogel contact lens materials were manufactured using a molecular imprinting technique to modify ciprofloxacin release kinetics. Various contact lens properties, including light transmission and surface wettability, were determined, and the in vitro ciprofloxacin release kinetics elucidated using fluorescence spectrophotometry. The materials then were evaluated for their ability to inhibit Pseudomonas aeruginosa growth in vitro and in an in vivo rabbit model of microbial keratitis.
  
  
  RESULTS
  Synthesized lenses had similar material properties to commercial contact lens materials. There was a decrease in light transmission in the shorter wavelengths due to incorporation of the antibiotic, but over 80% light transmission between 400 and 700 nm. Modified materials released for more than 8 hours, significantly longer than unmodified controls (P < 0.05). In vivo, there was no statistically significant difference between the number of colony-forming units (CFU) recovered from corneas treated with eye drops and those treated with one of two modified contact lenses (P > 0.05), which is significantly less than corneas treated with unmodified control lenses or those that received no treatment at all (P < 0.05).
  
  
  CONCLUSIONS
  These novel contact lenses designed for the extended release of ciprofloxacin may be beneficial to supplement or augment future treatments of sight-threatening microbial keratitis.
authors.affiliation: Centre for Contact Lens Research, School of Optometry & Vision Science, University of Waterloo, Waterloo, Ontario, Canada.
authors.forename: Alex
authors.initials: A
authors.lastname: Hui
authors.affiliation: School of Optometry and Vision Science, University of New South Wales, Sydney, New South Wales, Australia.
authors.forename: Mark
authors.initials: M
authors.lastname: Willcox
authors.affiliation: Centre for Contact Lens Research, School of Optometry & Vision Science, University of Waterloo, Waterloo, Ontario, Canada.
authors.forename: Lyndon
authors.initials: L
authors.lastname: Jones
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000493:pharmacokinetics / Q000627:therapeutic use; D002939:Ciprofloxacin / Q000493:pharmacokinetics* / Q000627:therapeutic use; D020099:Coated Materials, Biocompatible; D003262:Contact Lenses, Extended-Wear; D003315:Cornea / Q000187:drug effects / Q000378:metabolism* / Q000473:pathology; D003692:Delayed-Action Preparations / Q000493:pharmacokinetics / Q000627:therapeutic use; D004195:Disease Models, Animal; D004867:Equipment Design; D015818:Eye Infections, Bacterial / Q000175:diagnosis / Q000188:drug therapy* / Q000382:microbiology; D006801:Humans; D007634:Keratitis / Q000175:diagnosis / Q000188:drug therapy* / Q000382:microbiology; D011552:Pseudomonas Infections / Q000175:diagnosis / Q000382:microbiology / Q000628:therapy*; D011550:Pseudomonas aeruginosa / Q000302:isolation & purification; D011817:Rabbits; D012826:Silicone Elastomers; D013050:Spectrometry, Fluorescence
chemical_list: D000900:Anti-Bacterial Agents; D020099:Coated Materials, Biocompatible; D003692:Delayed-Action Preparations; D012826:Silicone Elastomers; D002939:Ciprofloxacin
keywords: ciprofloxacin; contact lens; drug delivery; microbial keratitis; molecular imprinting