Neutron and X-Ray reflectivity studies at solid-liquid interfaces: the interaction of a peptide with model membranes

A neutron reflectivity structural study of model biological membranes in th e gel phase interacting with a 16 amino-acid peptide is presented. Membrane s were prepared with the Langmuir-Schaeffer technique and measurements were done at the solid/liquid interface. Details of the structure at the interf ace were obtained at 1 Angstrom resolution. While with neutral lipids no sp ecific interaction is detected, in presence of negative charges in the memb rane the peptide interacts mainly with the lipid headgroups. The complement arity of neutron and synchrotron radiation measurements is mentioned. (C) 2 000 Elsevier Science B.V. All rights reserved.