While membrane proteins are not generally amenable to crystallisation they are very stable within hydrophobic environments. The production of hydrophobic layers at interfaces via lipids or modified alkanes provides an environment that is readily produced on planar silicon surfaces, is stable and mimics some of the properties of the cell membrane. One may attempt either to insert membrane proteins into preformed layers, codeposit with the membrane mimic or form a membrane mimic around the predeposited protein. We have taken the latter approach with two porins, OmpA and OmpF. This presentation will focus on our Neutron Reflectometry (NR) studies of the OmpA system where we have used magnetic contrast to enhance the information content of the scattering data. OmpA is a monomeric beta barrel membrane protein which we have engineered firstly to include a single cysteine residue enabling binding to gold surfaces with controlled orientation and secondly a ZZ domain from Staphylococcus aureus has been incorporated to give an accessible antibody binding site. We use NR to in situ follow the development of the surface structure at each step of the process from OmpA deposition, membrane mimic deposition, IgG binding and then antigen binding to the IgG. The figure shows a cartoon representative of the complex at an intermediate stage of complexation with the incoming and reflected neutron beam indicated.