Authors
Abstract
A simple, cost-effective, sensitive and highly selective method for the detection of caffeine has been developed at graphene modified carbon paste electrodes (GME). We synthesis of graphene oxide (GO) derived from bituminous coal by improved modified Hummers method. The synthesized graphene were characterized by UV-Visible Spectroscopy, FT-IR and Raman Spectroscopy, X-ray Diffraction Studies, Field Emission Scanning Electron Microscopy (FE-SEM) and High Resolution Transmission Electron Microscopy (HR-TEM). An electrochemical behavior of caffeine at the coal derived from graphene modified electrode was investigated by cyclic voltammetry (CV) and chronoamperometry (CA). By way of a result, graphene modified electrode (GME) showed good electrocatalytic activity towards the oxidation of caffeine. Under the optimized tentative conditions, caffeine was sensed in the concentration range from 0.2 to120 µmol L -1 with a detection limit of 90 nm molL -1 at a signal-to-noise ratio = 3. Hence, the graphene modified electrode (GME) could be used for the determination of caffeine in soft-drinks samples with high sensitivity and good selectivity. In this chronoamperometry shows a high catalytic currents are desirable for applications such as use in sensors.
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