title: Bacterial adhesion to unworn and worn silicone hydrogel lenses.
abstract: OBJECTIVE
  The objective of this study was to determine the bacterial adhesion to various silicone hydrogel lens materials and to determine whether lens wear modulated adhesion.
  
  
  METHODS
  Bacterial adhesion (total and viable cells) of Staphylococcus aureus (31, 38, and ATCC 6538) and Pseudomonas aeruginosa (6294, 6206, and GSU-3) to 10 commercially available different unworn and worn silicone hydrogel lenses was measured. Results of adhesion were correlated to polymer and surface properties of contact lenses.
  
  
  RESULTS
  S. aureus adhesion to unworn lenses ranged from 2.8 × 10 to 4.4 × 10 colony forming units per lens. The highest adhesion was to lotrafilcon A lenses, and the lowest adhesion was to asmofilcon A lenses. P. aeruginosa adhesion to unworn lenses ranged from 8.9 × 10 to 3.2 × 10 colony forming units per lens. The highest adhesion was to comfilcon A lenses, and the lowest adhesion was to asmofilcon A and balafilcon A lenses. Lens wear altered bacterial adhesion, but the effect was specific to lens and strain type. Adhesion of bacteria, regardless of genera/species or lens wear, was generally correlated with the hydrophobicity of the lens; the less hydrophobic the lens surface, the greater the adhesion.
  
  
  CONCLUSIONS
  P. aeruginosa adhered in higher numbers to lenses in comparison with S. aureus strains, regardless of the lens type or lens wear. The effect of lens wear was specific to strain and lens. Hydrophobicity of the silicone hydrogel lens surface influenced the adhesion of bacterial cells.
authors: Brien Holden Vision Institute, University of New South Wales, Sydney, New South Wales, Australia.
authors: Ajay Kumar
authors: AK
authors: Vijay
authors: Hua
authors: H
authors: Zhu
authors: Jerome
authors: J
authors: Ozkan
authors: Duojia
authors: D
authors: Wu
authors: Simin
authors: S
authors: Masoudi
authors: Rani
authors: R
authors: Bandara
authors: Roya N
authors: RN
authors: Borazjani
authors: Mark D P
authors: MD
authors: Willcox
mesh_terms: D000328:Adult; D001422:Bacterial Adhesion / Q000502:physiology*; D015169:Colony Count, Microbial; D003263:Contact Lenses, Hydrophilic / Q000382:microbiology*; D005260:Female; D006801:Humans; D008297:Male; D012826:Silicone Elastomers; D013212:Staphylococcus epidermidis / Q000502:physiology*; D013499:Surface Properties
chemical_list: D012826:Silicone Elastomers