Statement of Purpose: Antifouling is one of the most important characteristics required for materials intended for biomedical applications. In can lead to the reducing protein adsorption and subsequent bacterial adhesion or platelet adhesion. It is hypothesized that the nonfouling ability is tightly correlated with a hydration layer near the surface which forms a physical and energetic barrier to prevent protein adsorption on the surface. So far, there are three hydrophilic materials, 2-hydroxyethyl methacrylate (HEMA), oligo (ethylene glycol) (OEG) or poly (ethylene glycol) (PEG) and zwitterionic polymers have been suggested to be resistant to protein adsorption in different testing settings. But the failure in protein adsorption testing in physiological relevant conditions (e.g. undiluted human blood serum or plasma) for the polyHEMA and likely decomposition of PEG and OEG groups by the oxygen and transition metal ions found in most biochemically relevant solutions have rendered the zwitterionic materials to be the choice for preparing the nonfouling surface layer.