title: An investigation into the antimicrobial mechanisms of action of two contact lens biocides using electron microscopy.
abstract: Polyquaternium-1 (PQ-1) and myristamidopropyl dimethylamine (MAPD) are biocides used commercially in a contact lens disinfecting solutions. Electron microscopy was used to provide further evidence on the mechanism(s) of action of these agents against a wide range of ocular pathogens including bacteria, fungi and protozoa. Both PQ-1 and MAPD caused multiple forms of damage to the organisms tested, evidenced by structural alterations, blebbing, leakage and cell destruction. The extent of damage and the selectivity against specific type of microorganisms was consistent with the antimicrobial activity of these agents. Although electron microscopy is a powerful tool, it has its limitations when used to examine the mode of action of biocides. Indeed, there was no evidence of gross structural alteration to Acanthamoeba castellani or Aspergillus fumigatus following treatment.
authors.affiliation: Welsh School of Pharmacy, Cardiff University, King Edward VII Avenue, Cardiff CF10 3XF, UK.
authors.forename: Caroline E
authors.initials: CE
authors.lastname: Codling
authors.forename: Anthony C
authors.initials: AC
authors.lastname: Hann
authors.forename: Jean-Yves
authors.initials: JY
authors.lastname: Maillard
authors.forename: A Denver
authors.initials: AD
authors.lastname: Russell
mesh_terms: D048248:Acanthamoeba castellanii / Q000187:drug effects / Q000648:ultrastructure; D000818:Animals; D002176:Candida albicans / Q000187:drug effects / Q000648:ultrastructure; D015169:Colony Count, Microbial; D018639:Contact Lens Solutions / Q000494:pharmacology*; D003261:Contact Lenses / Q000382:microbiology / Q000469:parasitology; D004203:Disinfection / Q000379:methods*; D066298:In Vitro Techniques; D046529:Microscopy, Electron, Transmission; D011108:Polymers / Q000494:pharmacology*; D011437:Propylamines / Q000494:pharmacology*; D011550:Pseudomonas aeruginosa / Q000187:drug effects / Q000648:ultrastructure; D012706:Serratia marcescens / Q000187:drug effects / Q000648:ultrastructure
chemical_list: D018639:Contact Lens Solutions; D011108:Polymers; D011437:Propylamines; C058655:polyquaternium 1; C401661:myristamidopropyl dimethylamine