The gram-negative bacterial membrane is of extreme medical importance. The two main lipid components of the outer membrane are lipopolysaccharides (LPS's) and DOPE. We will produce floating supported bilayers (FSB) with an asymmetric outer bilayer; the inner leaflet - DOPE, and the outer leaflet LPS. Prior to the neutron reflection studies as a function of temperature and salt concentration the FSBs will have been characterised by Impedance Spectroscopy. The antibacterial toxin colicin N will be allowed to interact with the bilayer to determine the extent of penetration into the extended LPS headgroup region. This work forms an important baseline for our future studies which will focus on extending the headgroup size of the LPS and our aims to incorporate membrane proteins into this mimic.