Plane Wave Density Functional Theory Studies of the Structural and the Electronic Properties of Amino Acids Attached to Graphene Oxide via Peptide Bonding

We studied the electronic and the structural properties of amino acids (alanine, glycine, and histidine) attached to graphene oxide (GO) by peptide bonding, via plane wave pseudopotential total-energy calculations within the local spin density approximation (LSDA). The HOMO-LUMO gap, the Hirshfeld charges, and the equilibrium geometrical structures exhibit keen variations depending on the species of the attached amino acid. The GO-amino acid system appears to be a good candidate as a biosensor.