VOLTAMMETRIC DETERMINATION OF RUPATADINE AT GRAPHENE MODIFIED GLASSY CARBON ELECTRODE

Electrochemical behavior of rupatadine, an anti- allergic drug was studied at graphene modified glassy carbon electrode in Britton-Robinson buffer (pH 6.5) by square wave voltammetry (frequency, 50 Hz; amplitude, 0.02 V; step potential, 0.005 V) and cyclic voltammetry (scan rates, 20- 100 mV/s) techniques. Cyclic voltammetry revealed the oxidation of rupatadine corresponding to N-dealkylation which is the major metabolic pathway of rupatadine in human body. Atomic force microscopy, scanning electron microscopy and electrochemical impedance spectroscopy were used to study the surface characteristics of the fabricated sensor. The electrode dynamic parameters were investigated and the oxidation mechanism was proposed. Lower limit of detection and quantification were achieved with the modified sensor as compared to the bare sensor due to enhancement in electron transfer process at the surface of modified sensor owing to greater electroactive surface area. The limit of detection was found to be 56.78 ng/ml and limit of quantification, 172.06 ng/ml at graphene modified glassy carbon electrode.