We have previously solved the structure by SANS of the complex between the outer membrane protein F of E coi and the toxin colicin N which is a large antibiotic protein. This was achieved in a mixture of deuterated and hydrogenated SDS. We believe that this the best approach to solving membrane protein complexes e.g. to render all membrane / detergent components invisible by accurate contrast matching. We are continuing this study using neutral detergents (Octyl glucopyranoside) and the next step is to use nanodisc techniques to capture small lipid bilayers and create conditions where these too are invisible across a wide range of D20 concentrations. Here we wish to use a mixture of hydrogenous and deuterated nanodisc proteins and phospholipids to observe the outer membrane protein F alone and in complex with the colicin N toxin. Detergent solubilised OMPF will be compared directly.