An investigation into the antimicrobial mechanisms of action of two contact lens biocides using electron microscopy

Contact lens care solution killing efficacy against Acanthamoeba castellanii by in vitro testing and live-imaging

“…A small number of studies have utilized electron microscopy to visualize the effects of contact lens solution biocides on Acanthamoeba. Codling et al [46] reported that trophozoites exposed to polyquaternium for three hours showed evidence of precipitation of cellular contents around the cell membrane and nuclear membrane. However, they did not observe any morphological alteration in myristamidopropyl dimethylamine exposed cells.…”

Increased Resistance of Contact Lens-Related Bacterial Biofilms to Antimicrobial Activity of Soft Contact Lens Care Solutions

“…54 The exact mechanisms by which these substances are lethal to microorganisms are unknown, but it is believed they induce cytoplasmic membrane damage in P. aeruginosa, S. marcescens, and S. aureus . 54, 55 …”

Broad Spectrum of Antibacterial Activity of a New Multipurpose Disinfecting Solution

“…32,34,35 ALDOX is reported to induce damage to the cytoplasmic membrane of fungi and bacteria. 31,32 The ISO 14729 standard is the method that contact lens disinfecting products must meet before market. The primary criteria of the standard require that the contact lens disinfection product must show greater than or equal to an average of a 3.0 log reduction at the minimum disinfection time against specified strains of bacteria of the stand-alone test described in the ISO standards for contact lens disinfecting solutions against the panel of recommended reference organisms, but also showed broad spectrum in vitro bactericidal activity against a range of clinical and environmental isolates.…”

“…POLYQUAD has mainly antibacterial activity, whereas ALDOX has predominantly antifungal and antiprotozoal activity. [31][32][33] POLYQUAD is a quaternary ammonium compound and is known to act on the bacterial cytoplasmic membrane and to cause coagulation of the cytoplasm. 32,34,35 ALDOX is reported to induce damage to the cytoplasmic membrane of fungi and bacteria.…”

“…[31][32][33] POLYQUAD is a quaternary ammonium compound and is known to act on the bacterial cytoplasmic membrane and to cause coagulation of the cytoplasm. 32,34,35 ALDOX is reported to induce damage to the cytoplasmic membrane of fungi and bacteria. 31,32 The ISO 14729 standard is the method that contact lens disinfecting products must meet before market.…”