The air/water interface works as the simplest model for screening protein adsorption. Many previous studies have been made to examine protein adsorption at this interface. However, relatively few studies have been made using neutron reflection, but yet it is the only technique that can reveal the adsorbed amount and layer thickness from which information about conformational orientation, volume fraction, deformation and possible unfolding could be inferred. It is thus the best technique to help understand why adsorption could lead to structural damage thereby undermining bioactivity. In this work, we propose to follow the dynamic adsorption of 3 model antibodies with controlled sequential modifications. The data will help us understand how sequential modifications affect the dynamic packing of the surface layers and the subsequent implications to structural instability.