title: Impact of contact lens materials on multipurpose contact lens solution disinfection activity against Fusarium solani.
abstract: OBJECTIVE
  To investigate the effects of eight different soft contact lenses on disinfection efficacy of a multipurpose solution (MPS) containing polyhexamethylene biguanide (PHMB) against Fusarium solani.
  
  
  METHODS
  Six silicone hydrogel lenses (galyfilcon A, senofilcon A, comfilcon A, enfilcon A, balafilcon A, and lotrifilcon B) and two conventional hydrogel lenses (polymacon and etafilcon A) were placed in polypropylene lens cases filled with MPS containing 0.0001% PHMB and soaked for 6, 12, 24, 72, and 168 hours. After each interval, depleted MPS from lens cases were removed and assayed for activity against F. solani according to International Organization for Standardization (ISO) 14729 stand-alone procedure. A portion was aliquoted for chemical analysis.
  
  
  RESULTS
  Soaking etafilcon A, balafilcon A, and polymacon lenses for 6 hours reduced the concentration of PHMB in MPS by more than half the stated labeled concentration, with concentrations below the limit of detection for etafilcon A-depleted and balafilcon A-depleted solutions after 12 and 72 hours of soaking, respectively. Except for comfilcon A-depleted solutions, all others failed to consistently obtain one log reduction of F. solani. The solutions soaked with etafilcon A, balafilcon A, and polymacon lenses for 24 hours or more lost all or almost all fungicidal activity against F. solani.
  
  
  CONCLUSIONS
  Over time, the disinfectant uptake by some lenses can significantly reduce the PHMB concentration and the fungicidal activity of the MPS against F. solani. Current ISO methodology does not address the reduction in microbiocidal efficacy when lenses are soaked in MPS. The ISO committee should consider adding "soaking experiments" to quantify the effect that contact lens materials have on the performance of MPSs.
authors.affiliation: Winchester Engineering and Analytical Center, Winchester, MA, USA.
authors.forename: Charles R
authors.initials: CR
authors.lastname: Clavet
authors.forename: Maria P
authors.initials: MP
authors.lastname: Chaput
authors.forename: Matthew D
authors.initials: MD
authors.lastname: Silverman
authors.forename: Megan
authors.initials: M
authors.lastname: Striplin
authors.forename: Megan E
authors.initials: ME
authors.lastname: Shoff
authors.forename: Anne D
authors.initials: AD
authors.lastname: Lucas
authors.forename: Victoria M
authors.initials: VM
authors.lastname: Hitchins
authors.forename: Malvina B
authors.initials: MB
authors.lastname: Eydelman
mesh_terms: D001645:Biguanides / Q000032:analysis; D015169:Colony Count, Microbial; D018639:Contact Lens Solutions / Q000032:analysis / Q000494:pharmacology*; D003263:Contact Lenses, Hydrophilic / Q000382:microbiology*; D004202:Disinfectants / Q000032:analysis / Q000494:pharmacology; D015821:Eye Infections, Fungal / Q000517:prevention & control; D060585:Fusariosis / Q000517:prevention & control; D005670:Fusarium / Q000187:drug effects* / Q000302:isolation & purification
chemical_list: D001645:Biguanides; D018639:Contact Lens Solutions; D004202:Disinfectants; C031233:polihexanide