DEVELOPMENT, FABRICATION, AND ELECTROCHEMICAL CHARACTERIZATION OF SCREEN-PRINTED CARBON ELECTRODES: A COMPREHENSIVE STUDY ON REPEATABILITY AND PERFORMANCE OPTIMIZATION

Abstract

Screen-printed carbon electrodes (SPCEs) have shown great promise as electrochemical sensing and analytical platforms because of their cost effectiveness, disposability and compatibility with hand-held instrumentation. This work reveals an in-depth investigation of the development, fabrication, optimization, and repeatability analysis of the screen-printed carbon electrodes fabricated using a controlled screen-printing process on different substrates. A systematic procedure was followed to characterize the electrochemical behavior of SPCEs using several electrochemical techniques such as cyclic voltammetry (CV), differential pulse voltammetry (DPV) and square wave voltammetry (SWV). The study involved material choices, developing ink formulation, substrate preparation, optimization of electrode geometry, and to evaluate intraelectrode and inter-electrode repeatability, strict protocols of electrochemical testing were carried out. Results show that optimized SPCEs have good electrochemical performance including low charge transfer resistance, high peak current executing and good reproducibility in several batches. The batch-to-batch consistency of the developed electrodes was evaluated and the results showed that the co-efficient of variation (CV) in peak current measurements obtained from 10 replicate electrodes was below 8%. Electrochemical impedance spectroscopy (EIS) analysis has shown well defined semicircular plots related to the diffusion limited mechanism of electron transfer. The potential for these screen-printed electrodes in point-of-care applications for diagnostics, environmental monitoring and electrochemical sensing applications in the laboratory is discussed. This work defines high standards of quality control and performance benchmarking requirements for SPCE fabrication which will lead to the development of projections of electroanalytical methodologies in research and industrial research.