In this study we will perform neutron reflectometry experiments on surfaces coated with thermoresponsive polymer oligo (ethylene glycol) methacrylates, whose biocompatibility (i.e. the ability of surfaces to resist the adsorption of cells or proteins) depends on the temperature. Biocompatibility is of crucial importance in biotechnology and biomedical application. Water is thought to have a relevant role to the inertness of a surface, but cannot be clearly understood unless more detailed information on the water structure within the coating will be obtained. Our study will take advantage of the thermoresoponsive properties of the polymer, in order to follow the evolution of the polymer structure and of the water profile from lower temperatures, where the polymer is biocompatible, to higher temperatures where biocompatibility is lost.