SERS and theoretical studies of arginine

Arginine amino acid (Arg) has been vibrationally studied through its infrared, Raman and surface-enhanced Raman scattering (SERS) spectra, and theoretical calculations. Net charge is used to predict the possibility to obtain the SERS spectrum of Arg in colloidal solution. The interpretation of the SERS spectral data suggests that the Arg–Ag nanoparticles interaction in a colloidal solution and in the case of the Arg coated by Ag is mainly verified through the guanidinium moiety. Theoretical calculations performed by using extended Hückel theory method for a model of Arg interacting with an Ag cluster support the observed SERS experimental result.