Real-Time Monitoring of Interactions between Solid-Supported Lipid Vesicle Layers and Short- and Medium-Chain Length Alcohols: Ethanol and 1-Pentanol

Abstract

Lipid bilayers represent the interface between the cell and its environment, serving as model systems for the study of various biological processes. For instance, the addition of small molecules such as alcohols is a well-known process that modulates lipid bilayer properties, being considered as a reference for general anesthetic molecules. A plethora of experimental and simulation studies have focused on alcohol’s effect on lipid bilayers. Nevertheless, most studies have focused on lipid membranes formed in the presence of alcohols, while the effect of n-alcohols on preformed lipid membranes has received much less research interest. Here, we monitor the real-time interaction of short-chain alcohols with solid-supported vesicles of dipalmitoylphosphatidylcholine (DPPC) using quartz crystal microbalance with dissipation monitoring (QCM-D) as a label-free method. Results indicate that the addition of ethanol at different concentrations induces changes in the bilayer organization but preserves the stability of the supported vesicle layer. In turn, the addition of 1-pentanol induces not only changes in the bilayer organization, but also promotes vesicle rupture and inhomogeneous lipid layers at very high concentrations.

Unraveling How Ethanol-Induced Conformational Changes Affect BSA Protein Adsorption onto Silica Surfaces

“…Note that the Δ f and Δ D shifts due to step 1 are caused by changes in the viscosity and density of the bulk solution, and not protein adsorption itself. It is thus important to compare Δ f and Δ D shifts only when the initial and final values were recorded in the same bulk solution. , For this reason, the results of protein adsorption in the water–ethanol mixtures (relative to the water–ethanol baseline without protein, before and after water–ethanol mixture washing) were evaluated along with the final adsorbate properties after aqueous buffer washing (relative to the initial baseline values in aqueous buffer).…”

Membrane Interactivity of Capsaicin Antagonized by Capsazepine

“…Capsaicin has an amphiphilic structure ( Figure 1 ), which may enable capsaicin to act on lipid bilayers. In addition to specific binding to target proteins, amphiphiles, including drugs and phytochemicals, can interact with lipid bilayers to affect membrane fluidity, permeability, elasticity and curvature [ 7 , 8 ], and membrane lipid phase transition and lipid bilayer thickness [ 8 , 9 ]. Such membrane interactions modulate the functions of membrane-embedded channels through protein conformational changes [ 10 ], mechanistically contributing to the pharmacological effects of amphiphilic anesthetics, analgesics, anti-inflammatory drugs and others [ 11 , 12 , 13 ].…”