Determination of doxorubicin by reduced graphene oxide/gold/polypyrrole modified glassy carbon electrode: A new preparation strategy

In this paper, an electrochemical sensor was developed based on the reduced graphene oxide (rGO)/gold (Au) nanoparticles/polypyrrole (PPy)/nanocomposite modified glassy carbon electrode (GCE) for determination of doxorubicin (DOX). To do this, pyrrole monomer was in-situ polymerized on the surface of rGO/Au modified electrode. The characterization results indicated on incorporation of Au and PPy among the rGO layers enhanced the conductivity and electron transfer properties of electrode. Respect to electrochemical properties and characterization analyses, the Au and pyrrole concentrations in the producing procedure were optimized. Electrochemical investigations revealed that a process involving the same number of protons and electrons during the electrooxidation reaction was taken place. The optimum pH was determined as 5.5. Also, electrochemical reaction followed by a homogenous chemical reaction and it was a surface-controlled quasi-reversible process. The modified electrodes exhibited a high sensitivity of 185 μA mM−1 and low detection limit of 0.02 μM with a wide linear range of 0.02 μM–25 mM. Additionally, the sensor exhibited excellent reproducibility and stability properties.