Poly(ethylene glycol) and hydroxy functionalized alkane phosphate mixed self-assembled monolayers to control nonspecific adsorption of proteins on titanium oxide surfaces.

The spontaneous formation of alkane phosphate self-assembled monolayers (SAMs) on titanium oxide was chosen as a tool to tailor the surface physicochemical properties in terms of nonspecific adsorption of proteins. For this aim, poly(ethylene glycol)-modified (PEG) alkane phosphate was codeposited with OH-terminated alkane phosphates. X-ray photoelectron spectroscopy and ellipsometry of the resulting mixed SAMs indicate that the PEG density can be controlled by varying the mole fraction of PEG-terminated phosphates in the solutions used during the deposition process, leading to surfaces with different degrees of protein resistance.