Comparative Electrochemical Performance of Screen Printed Carbon, Gold and Graphene Electrodes

A comparative analysis of the electrochemical performance of screen printed carbon (SPCE), gold (SPGE), and graphene (SPGrE) electrodes is presented before integration into electrochemical biosensors. The electrodes were systematically examined based on key electrochemical parameters, including charge transfer kinetics, electrochemical reproducibility, and stability, considering [Fe(CN)6]<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3−/4−</sup> as a typical redox analyte using cyclic voltammetry (CV), differential pulse voltammetry (DPV), and electrochemical impedance spectroscopy (EIS). Results indicate that all the bare screen printed electrodes (SPEs) demonstrate significant irreproducibility (>10% of RSD) with poor stability of the electroactive surface. The graphene electrodes exhibit superior electrocatalytic properties with higher interfacial charge transfer rate constant (2.30x10<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-6</sup> cms<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-1</sup>) compared to the SPCE (1.40x10<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-6</sup> cms<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-1</sup>) and SPGE (1.72x10<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-6</sup> cms<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-1</sup>) surfaces. The findings provide valuable insights into the relative merits and drawbacks of SPEs, guiding the selection of suitable electrode materials for diverse biosensing applications.