Interaction of triclosan with eukaryotic membrane lipids

Publisher Website
Google Scholar
Abstract
The possibility that triclosan and PVM/MA (polyvinylmethyl ether/maleic acid) copolymer, additives to dentrifrices, could interact with eukaryotic membrane lipids was studied by two methods: first, by determining the pressure/molecular area isotherms at 37°C of glycerophospholipid monolayers, using the Langmuir technique; and second, by phase‐transition parameters in liposomes of the same lipids, using differential scanning calorimetry (DSC). Triclosan interacted, in a concentration‐independent manner, with monolayers of saturated phosphatidylcholines (PC; i.e. markers of the outer membrane leaflet of eukaryotic cells). Triclosan and PVM/MA copolymer mixtures were shown to clearly interact in a concentration‐dependent manner with PC. Triclosan was found to interact with liposomes of saturated and unsaturated phosphatidylcholines and phosphatidylserines (PS; i.e. markers of the inner membrane leaflet of eukaryotic cells), and saturated ethanolamines (PE; i.e. markers of the inner membrane leaflet of eukaryotic cells), resulting in a decrease of the lipid melting temperature (Tm). PVM/MA copolymer changed the Tm of PS, PC, and PE in different manners. By adding PVM/MA or triclosan–PVM/MA copolymer mixtures to 1‐stearoyl‐2‐oleoyl‐sn‐glycero‐3‐phosphoserine (SOPS) no lipid transitions were detected. A biphasic change of the PC transition temperature resulted when triclosan or triclosan PVM/MA copolymer mixtures were added, indicating domain formation and change of the lipid polymorphism.