Interaction Forces of a Supported DOPC Bilayer in the Presence of the General Anaesthetic Halothane — An Atomic Force Microscopy Study

Abstract

In this study atomic force microscopy (AFM) was used to study the effect of halothane on a supported dioleoylphosphatidylcholine (DOPC) bilayer under conditions of high anaesthetic loading. In a previous study we demonstrated that bilayer restructuring occurs as a result of halothane incorporation. Force measurements using AFM indicate an initial decrease in adhesive forces and compressibility between the bilayer and AFM tip, followed by an increase in adhesion properties as a function of incubation time. This effect is attributed to the location and dynamic redistribution of halothane within the bilayer.

Atomic Force Microscopy: Interaction Forces Measured in Phospholipid Monolayers, Bilayers and Cell Membranes

“…Slowly cooling the system back showed that the two higher-temperature transitions at 42-52 and 53-60 • C are reversible and that the bilayer can be restored to its initial thickness [61]. A DOPC bilayer, which exists in a fluid phase at room temperature, when heated shows thickness reduction as well as an increase in surface coverage [62], but no domain formation. Previous studies have established the L β -L α phase transition temperature for DPPC at 41 • C [63].…”