sodium-dodecyl-sulfate and octenidine

New antifungal agents are needed to treat life-threatening fungal infections, particularly with the development of resistance. Surface-active antifungals have the advantages of minimizing host toxicity and the emergence of drug resistance. We have developed a time-dependent drug exposure assay that allows us to rapidly investigate the mechanism of surface-active antifungal drug action. The assay uses a multidrug pump-deficient strain of Saccharomyces cerevisiae and the potentiometric dye 3,3'-dipropylthiacarbocyanine iodide [diS-C₃(3)] and can assess whether cells are depolarized, hyperpolarized, or permeabilized by drug exposure. In this work, we investigated the mechanisms of action of five surface-active compounds: SDS, nystatin, amphotericin B, octenidine dihydrochloride, and benzalkonium chloride. The diS-C₃(3) time-dependent drug exposure assay can be used to identify the mechanisms of action of a wide range of drugs. It is a fast and cost-effective method for screening drugs to determine their lowest effective concentrations.

Topics: Amphotericin B; Antifungal Agents; Benzalkonium Compounds; Cell Membrane Permeability; Imines; Kinetics; Microbial Sensitivity Tests; Nystatin; Pyridines; Saccharomyces cerevisiae; Sodium Dodecyl Sulfate; Spectrometry, Fluorescence; Surface-Active Agents