title: Plasma surface modification of rigid contact lenses decreases bacterial adhesion.
abstract: OBJECTIVE
  Contact lens safety is an important topic in clinical studies. Corneal infections usually occur because of the use of bacteria-carrying contact lenses. The current study investigated the impact of plasma surface modification on bacterial adherence to rigid contact lenses made of fluorosilicone acrylate materials.
  
  
  METHODS
  Boston XO and XO2 contact lenses were modified using plasma technology (XO-P and XO2-P groups). Untreated lenses were used as controls. Plasma-treated and control lenses were incubated in solutions containing Staphylococcus aureus or Pseudomonas aeruginosa. MTT colorimetry, colony-forming unit counting method, and scanning electron microscopy were used to measure bacterial adhesion.
  
  
  RESULTS
  MTT colorimetry measurements showed that the optical density (OD) values of XO-P and XO2-P were significantly lower than those of XO and XO2, respectively, after incubation with S. aureus (P < 0.01). The OD value of XO-P was also much lower than that of XO after incubation with P. aeruginosa (P < 0.01). Colony-forming unit counting revealed that a significantly lower number of bacterial colonies attached to the XO-P versus XO lenses and to the XO2-P versus XO2 lenses incubated with S. aureus (P < 0.01). Fewer bacterial colonies attached to the XO-P versus XO lenses incubated with P. aeruginosa (P < 0.01). Further, scanning electron microscopy suggested different bacterial adhesion morphology on plasma-treated versus control lenses.
  
  
  CONCLUSIONS
  Plasma surface modification can significantly decrease bacterial adhesion to fluorosilicone acrylate contact lenses. This study provides important evidence of a unique benefit of plasma technology in contact lens surface modification.
authors.affiliation: Department of Ophthalmology, The First Affiliated Hospital of Soochow University, Suzhou, China.
authors.forename: Yingming
authors.initials: Y
authors.lastname: Wang
authors.forename: Xuefeng
authors.initials: X
authors.lastname: Qian
authors.forename: Xiaofeng
authors.initials: X
authors.lastname: Zhang
authors.forename: Wei
authors.initials: W
authors.lastname: Xia
authors.forename: Lei
authors.initials: L
authors.lastname: Zhong
authors.forename: Zhengtai
authors.initials: Z
authors.lastname: Sun
authors.forename: Jing
authors.initials: J
authors.lastname: Xia
mesh_terms: D001422:Bacterial Adhesion; D015169:Colony Count, Microbial; D003261:Contact Lenses / Q000382:microbiology*; D008855:Microscopy, Electron, Scanning; D011108:Polymers; D011550:Pseudomonas aeruginosa / Q000502:physiology*; D013211:Staphylococcus aureus / Q000502:physiology*; D013499:Surface Properties
chemical_list: D011108:Polymers