title: Release of Fluconazole from Contact Lenses Using a Novel In Vitro Eye Model.
abstract: OBJECTIVE
  Rapid drug release followed by a plateau phase is a common observation with drug delivery from contact lenses (CLs) when evaluated in a vial. The aim of this study was to compare the release of fluconazole from seven commercially available daily disposable CLs using a conventional vial-based method with a novel in vitro eye model.
  
  
  METHODS
  An eye model was created using two 3-dimensional printed molds, which were filled with polydimethylsiloxane to obtain an inexpensive model that would mimic the eyeball and eyelid. The model was integrated with a microfluidic syringe pump, and the flow-through was collected in a 12-well microliter plate. Four commercial daily disposable conventional hydrogels (nelfilcon A, omafilcon A, etafilcon A, ocufilcon B) and three silicone hydrogels (somofilcon A, narafilcon A, delefilcon A) were evaluated. These CLs were incubated with fluconazole for 24 h. The drug release was measured in a vial containing 4.8 mL of phosphate-buffered saline and in the polydimethylsiloxane eye model with a 4.8-mL tear flow across 24 h.
  
  
  RESULTS
  Overall, conventional hydrogel CLs had a higher uptake and release of fluconazole than silicone hydrogel CLs (p < 0.05). A higher drug release was observed in the vial condition compared with the eye model (p < 0.001). In the vial system, the drugs were rapidly released from the CL within the first 2 h, followed by a plateau phase. In contrast, drug release in the eye model under low tear volume was sustained and did not reach a plateau across 24 h (p < 0.05).
  
  
  CONCLUSIONS
  Rapid drug release results from using a vial as the release system. Under low tear volume at physiological tear flow, commercial CLs can maintain a sustained drug release profile for up to 24 h. However, eyes with fungal keratitis may have increased tearing, which would significantly accelerate drug release.
authors.affiliation: *MSc †BSc ‡PhD, BSOptom, MSc, FAAO §PhD, FCOptom, FAAO Centre for Contact Lens Research, School of Optometry and Vision Science, Waterloo, Ontario, Canada (C-MP, LNS, LWJ); Department of Mechanics, Material Science and Engineering, Wroclaw University of Technology, Wroclaw, Poland (MB); and Medella Health, Kitchener, Ontario, Canada (HG).
authors.forename: Chau-Minh
authors.initials: CM
authors.lastname: Phan
authors.forename: Magdalena
authors.initials: M
authors.lastname: Bajgrowicz
authors.forename: Huayi
authors.initials: H
authors.lastname: Gao
authors.forename: Lakshman N
authors.initials: LN
authors.lastname: Subbaraman
authors.forename: Lyndon W
authors.initials: LW
authors.lastname: Jones
mesh_terms: D000935:Antifungal Agents / Q000008:administration & dosage / Q000493:pharmacokinetics*; D003263:Contact Lenses, Hydrophilic; D004209:Disposable Equipment; D016503:Drug Delivery Systems; D015821:Eye Infections, Fungal / Q000188:drug therapy; D015725:Fluconazole / Q000008:administration & dosage / Q000493:pharmacokinetics*; D006801:Humans; D020136:Hydrogel, Polyethylene Glycol Dimethacrylate; D008954:Models, Biological; D012826:Silicone Elastomers; D013056:Spectrophotometry, Ultraviolet
chemical_list: D000935:Antifungal Agents; D012826:Silicone Elastomers; D020136:Hydrogel, Polyethylene Glycol Dimethacrylate; D015725:Fluconazole