Nitrated tyrosine adsorption on metal-doped graphene: A DFT study

The adsorption of nitrated tyrosine on the intrinsic and metal-doped graphene was studied by density functional theory in order to explore the possibility of using graphene-based biosensor to detect the protein tyrosine nitration (PTN). The configurations of (a) phenolic ring coordination and (b) nitro group coordination on the graphene were compared. It was found that nitrated tyrosine was physisorbed on the intrinsic graphene and favored coordinating with the intrinsic graphene by phenolic ring, while chemisorption was observed on Au, Cr and Ni-doped graphene with high binding energy. In contrast, the nitrated tyrosine favored coordinating with the metal-doped graphene through metal-nitro group configuration. The electronic density of states analysis showed strong orbital hybridization between the nitro group and metal-doped graphene. The calculation indicated that the metal-doped graphene was sensitive to the tyrosine nitration, thus suggesting the potential application of metal-doped graphene for PTN detection.