Following our previous study of adsorption of Fc, Fab and the constituent mAb COE-3, we continue to explore how two bioengineered mAbs adsorb at the oil/water interface by neutron reflection. Inter is preferred because we have built technical capability on this instrument. COE-7 and COE-8 have enlarged Fab and Fc domains and reduced globular stability. Our specific aims are to (a) determine the actual thickness and volume fraction of and (b) the effect of pH on the interfacial distribution. The results will enable us to compare their extent of distributions into the oil region with other globular proteins at the interface. We can then answer if all the globular proteins unfold and produce characteristic segment distributions into the oil region.