Induced structural changes of a supported planar bilayer after exposure to halothane — A real-time atomic force microscopy study

Abstract

Atomic force microscopy (AFM) was used to study the effect of the general anesthetic halothane on a supported DOPC phospholipid bilayer, under conditions of high anaesthetic loading. The presence of the anaesthetic in the lipid-induced restructuring of the supported bilayer, erosion of the bilayer from the mica surface, and the formation of lipid aggregates. Addition of halothane to lipid vesicles prior to adsorption on the mica surface inhibited the lysis of adsorbed vesicles and thus no planar bilayer formation was observed.Key words: lipid bilayer restructuring, atomic force microscopy, halothane, anesthesis.

Role of Unsaturated Lipid and Ergosterol in Ethanol Tolerance of Model Yeast Biomembranes

“…Inclusion of the unsaturated lipid provides a model system that, in comparison to our previous studies (21,23), more closely resembles a real yeast plasma membrane, which contains a large number of unsaturated lipid species (35). AFM has been widely used to study the effects of ethanol (23,24,33,36) and other anesthetics (32,37,38) on model supported membranes, as it provides high-resolution details of both the morphology and the membrane thickness. However, the discrepancy in the amounts of ethanol (5-10 times higher), long incubation periods, and reheating after bilayer formation required to induce interdigitation in supported versus unsupported membranes of a single saturated lipid, due to the interaction with the support, presented a barrier for this type of ethanol study (23,33,36).…”

AFM Studies of the Effect of Temperature and Electric Field on the Structure of a DMPC−Cholesterol Bilayer Supported on a Au(111) Electrode Surface

“…Phospholipid bilayers supported on planar solid surfaces serve as popular models of biomimetic membranes to study protein adsorption, peptide−membrane interactions, ion transport, lateral membrane inhomogeneities, phase transitions, and mechanical membrane properties. − Such supported bilayer membranes (s-BLMs) can be formed at surfaces of a variety of materials including glass, silicon, silicon nitride, quartz, and mica, using chiefly either a combination of Langmuir−Blodgett and Langmuir−Schaefer (LB-LS) deposition , or vesicle fusion. ,− Lipid bilayers can also be tethered via functionalization to a gold surface to serve as platforms for biosensors . s-BLMs may also be directly deposited (formed by either the vesicle fusion or LB-LS methods) onto an electrode to study the effect of the static electric field on the membrane structure and stability.…”

STM Studies of Fusion of Cholesterol Suspensions and Mixed 1,2-Dimyristoyl-sn-glycero-3-phosphocholine (DMPC)/Cholesterol Vesicles onto a Au(111) Electrode Surface

“…Because of its simplicity, this is a very popular method of SPB formation. The mechanism of spreading vesicles at glass, quartz, mica, and mercury has been investigated intensively. – These studies determined that at hydrophilic surfaces the mechanism of vesicle spreading involves several consecutive steps such as vesicle adsorption, rupture, fusion, and movements of fragments of the bilayer at the solid surface by sliding or rolling by a tank-tread like motion. ,, It has also been established that the kinetics of vesicle fusion is controlled by mass transport, temperature, size, and composition of vesicles, nature of the solid surface, and the presence of ions in solution. For a recent review see Richter et al…”