Characterization and Reproducibility Assessment of Commercial Screen-Printed Carbon Electrodes

Screen-printed carbon electrodes (SPCEs) are widely used in electrochemical and electroanalytical applications due to their low cost, disposability, compatibility with portable instrumentation, and favorable material properties such as high surface area and tunable surface chemistry [1,2]. These attributes, combined with the possibility of surface functionalization and incorporation of nanostructured carbon materials, make SPCEs highly attractive for sensitive and selective sensing platforms, ranging from environmental monitoring to biomedical analysis [3,4]. Despite their widespread commercial availability and apparent standardization, SPCEs from different manufacturers, or even different batches from the same manufacturer, can exhibit significant variability in electrochemical performance, which may critically influence reproducibility and reliability of measurements [2,5]. For this reason, a systematic characterization is essential to assess to what extent these electrodes can be considered “equivalent” or interchangeable in practical applications. In this study, a range of commercially available SPCEs were systematically compared. Electrochemical characterization was carried out using cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) to evaluate key parameters such as electroactive surface area, electron transfer kinetics, background currents, and signal stability, using the ferri/ferrocyanide redox couple as a benchmark [3,4]. The assessment focused particularly on electrode-to-electrode reproducibility, batch-to-batch variability, and signal dispersion across multiple units from different commercial sources, highlighting differences that can be significant even among devices with nominally similar specifications [1,5]. Minimal attention was given to morphological and compositional analysis to support the electrochemical data. The results aim to provide practical benchmarking criteria for selecting SPCEs, helping researchers and practitioners to balance the advantageous electrochemical properties and inherent selectivity of these electrodes with reproducibility requirements, thus supporting more reliable measurements in electrochemical and biosensing applications [5,6]. As a complementary and non-binding extension, preliminary investigations on surface modification, including electropolymerization, may be conducted to further explore surface-dependent performance differences and potential improvements in selectivity. [1] Crapnell, R. D., & Banks, C. E, ChemElectroChem, 2024, 11. [2] Andreeva, R., Tsanev, A., Avdeev, G., Stoychev, D., Metals, 2025, 15. [3] Taleat, Z., Khoshroo, A., Mazloum-Ardakani, M., Microchimica Acta, 2014, 181, 865-891. [4] Barton, J., García, M.B.G., Santos, D.H. et al., Microchim Acta, 2016, 183, 503–517. [5] Lihua Zhao, Hongliang Han, Zhanfang Ma, Biosensors and Bioelectronics, 2018, 101, 304-310. [6] Subramaniam, S. R., Abidin, Z. Z., Issa, M. A., Harun, N. H., & Pudza, M. Y., Water, Air, and Soil Pollution, 2025, 236(14)