Jornal de Técnicas Analíticas e Bioanalíticas

Abstrato

Graphene and Polyaniline Composite Modified Glassy Carbon Electrode for Electrochemical Determination of Doripenem and Meropenem Metabolites

Sreedhar NY, Sivaprasad M, Swarupa Ch, Dhananjayulu M and Jayapal MR

The theme of this study was the preparation, characterization, and application of a polyaniline (PAN) and graphene composite modified glassy carbon electrode (PAN/Gr/GCE) for the voltammetric determination of doripenem (DPM) and meropenem metabolites (MPM) in human urine and serum samples. The morphological study of the PAN/ Gr/GCE composite was examined by scanning electron microscopy (SEM) and cyclic voltammetry (CV). The electrochemical behaviour of DPM and MPM at the PAN/Gr/GCE were investigated using cyclic voltammetry in Ag/ AgCl/KCl supporting electrolyte at pH 2.0-10.0 in phosphate buffer solution. The linear dependence of current versus concentration was reached in a wide concentration range from 2.5×10^-7 M to 3.5×10^-4 M using cyclic voltammetry and differential pulse voltammetric methods. In acidic media a non-reversible diffusion controlled reduction involving two protons and two electrons occurs at carbon and nitrogen double bond (C=N) in the metabolites. The best electroanalytical performances of this composite electrode were achieved with the detection limits 3.6×10^-9 M and 1.75×10^-9 M for DPM and MPM respectively. The simplicity of preparation, high sensitivity and stability of this composite electrode should open novel avenues and applications for fabricating robust sensors for detection of DPM and MPM in human urine and serum samples.