Neutron Reflectivity Study on Bio-molecules using Bio-mimetic Membranes

Abstract

X-ray and neutron reflectometry are powerful techniques for observing depth profiles of surfaces and interfaces on the scale from nanometers to sub-micrometers in a non-destructive manner. In particular, neutrons can penetrate materials, distinguish isotopes, and have magnetic spin moment. This enables us to observe protein structure, especially for the interaction with phospholipid bilayers, with special techniques. In this review, we introduce two protein studies using neutron reflectometry: one is the cholera toxin CTAB₅ in contact with a Langmuir monolayer of phospholipid/ganglioside mixture, and the other is the Escherichia coli outer membrane protein OmpF supported on a gold surface with a thiolipid/phospholipid bilayer.