In-situ functionalization of aniline oligomer onto layered graphene sheet and study of its application on electrochemical detection of ascorbic acidin food samples

Aniline oligomers are considered as one of the electron transfer mediators for the electrochemical oxidation of ascorbic acid. The electrochemical oxidation of ascorbic acid was investigated using aniline oligomerfunctionalized polymer modified electrode. In the present investigation, we demonstrated a novel methodology for the in-situ modification of aniline oligomer onto the layered graphene sheet by using diazonium salt form as precursor molecule. An enhanced electrocatalytic current was obtained for the oxidation of ascorbic acid using aniline pentamer-functionalized reduced graphene oxide (APrGO). Detailed studies have been carried out to study the surface modified rGO by FTIR spectroscopy. A linear relationship between peak current against the concentration of ascorbic acid was observed within the ranges from 1$\mu$M to 10$\mu$M. The detection limit was measured at signal/noise (S/N) of 3. The present method can be utilized for the electrochemical detection of ascorbic acid present in food products like fruit juices.