Neutron Reflectivity as Method to Study in‐Situ Adsorption of Phospholipid Layers to Solid‐Liquid Interfaces

Abstract

The design and structure of biomimetic films along a planar surface is of tremendous interest for the development of biocompatible interfaces, the construction of biosensors based on membrane receptors, and as biophysical model systems for studying the interaction of biomolecules with membrane surfaces. A basic step in the design of such systems is the preparation of phospholipid molecules in the form of planar bilayers along adequate interfaces to mimic the interface of a biological membrane.

Thermal stability, mechanical properties and water content of bacterial protein layers recrystallized on polyelectrolyte multilayers

“…The thickness and the SLD of the bare polyelectrolyte multilayer cushion are typical for the studied system. 24 The fitting of the reflectivity curve of the recrystallized S-protein layer was possible using a two-layer model. The first layer represents the polyelectrolyte multilayer cushion, while the second one takes into account the S-protein layer.…”

“…20 More recently, QCM-D has been combined with (i) ellipsometry and atomic force microscopy to follow lipid vesicle deposition on mica, 21 (ii) optical waveguide lightmode spectroscopy to investigate the density, the refractive index and the structure of adsorbed native and denatured proteins layers, 22 and (iii) surface plasmon resonance to show that the water mass sensed by the quartz microbalance not only originates from water entrapped within supramolecular assemblies and from water dynamically entrapped between adsorbed biomacromolecules. 23 Neutron reflectometry has been used to monitor the in situ adsorption of phospholipid layers at the solid liquid interface 24 and has been combined with atomic force microscopy to study the affinity of polyelectrolytes to the bacterial surface layer. 25 In this work we have combined quartz microbalance with dissipation monitoring, atomic force microscopy and neutron reflectometry to investigate the recrystallization and structure of bacterial cell surface layers (SbpA proteins from Bacillus sphaericus CCM2177) on an anionic-terminated polyelectrolyte multilayer (PEM) cushion.…”

Bilayer Edges Catalyze Supported Lipid Bilayer Formation

“…Understanding the mechanism is crucial to increasing SLB use and has motivated a variety of studies. SLB formation has been observed at the single vesicle level, using fluorescence microscopy (17,18) and atomic force microscopy (AFM) (12,15,16,19,20), as well as in bulk, using quartz crystal microbalance with dissipation (QCM-D) (10,15,(21)(22)(23)(24), surface plasmon resonance (22,23), ellipsometry (13,15,25), and x-ray (26) and neutron (27) reflectivity.…”

Native supported membranes on planar polymer supports and micro-particle supports

“…Specular X-ray/neutron reflectivity is a powerful tool to determine the thickness, roughness, and scattering length density of the layers buried under water ( Fig. 2a and b) (Gutberlet et al, 2004;Majewski et al, 1998;Rehfeldt et al, 2006). Especially, the scattering length density reflects the volume fraction (and thus the chemical potential) of water in polymer supports, as well as the density of polymer chains in the direction particular to the surface.…”