title: Transparent nanostructured photochromic UV-blocking soft contact lenses.
abstract: We aim to develop transparent UV-blocking photochromic soft contact lenses via polymerization of a bicontinuous nanoemulsion.
  
  
  
  Transparent nanostructured polymers were prepared by incorporating a polymerizable surfactant and thermal initiator together with water, monomers, UV blockers and photochromic dyes. The polymers were characterized using oxygen permeometer, tensile tester, electron microscope, UV spectrophotometer, corneal cell culture and testing in rabbits.
  
  
  
  The polymers have good oxygen permeability, water content, stiffness, strength and UV-blocking ability comparable to commercial UV-blocking soft contact lenses. Their response to UV light is comparable to photochromic spectacle lenses, particularly in reverse transition from colored to colorless state. They are nontoxic and nonleaching.
  
  
  
  Our photochromic UV-blocking contact lenses provide a novel alternative to photochromic spectacles.
authors.affiliation: Institute of Bioengineering & Nanotechnology, 31 Biopolis Way, The Nanos, Singapore 138669, Singapore.
authors.forename: Y Shona
authors.initials: YS
authors.lastname: Pek
authors.affiliation: Institute of Bioengineering & Nanotechnology, 31 Biopolis Way, The Nanos, Singapore 138669, Singapore.
authors.forename: Hong
authors.initials: H
authors.lastname: Wu
authors.affiliation: Institute of Bioengineering & Nanotechnology, 31 Biopolis Way, The Nanos, Singapore 138669, Singapore.
authors.forename: Edwin Py
authors.initials: EP
authors.lastname: Chow
authors.affiliation: Institute of Bioengineering & Nanotechnology, 31 Biopolis Way, The Nanos, Singapore 138669, Singapore.
authors.forename: Jackie Y
authors.initials: JY
authors.lastname: Ying
mesh_terms: D000818:Animals; D002460:Cell Line; D004396:Coloring Agents / Q000737:chemistry; D003263:Contact Lenses, Hydrophilic; D003315:Cornea / Q000166:cytology; D004655:Emulsions / Q000737:chemistry; D006801:Humans; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure; D010100:Oxygen / Q000737:chemistry; D010539:Permeability; D011108:Polymers / Q000737:chemistry*; D011817:Rabbits; D014466:Ultraviolet Rays
chemical_list: D004396:Coloring Agents; D004655:Emulsions; D011108:Polymers; D010100:Oxygen
keywords: contact lenses; nanoemulsions; nanostructures; photochromic materials