Copper‐nanostructure‐modified laser‐scribed electrodes based on graphitic carbon for electrochemical detection of dopamine and glucose

Abstract

Abstract BACKGROUND Carbon‐based nanostructures have been attracting major interest in many research fields, including chemical and biological sensing, because of their unique structural dimensions and excellent physical, chemical and mechanical properties. A recently developed laser scribing approach allows design and fabrication of flexible, graphitic carbon‐based substrates for (bio‐)electrochemical applications, as it provides highly robust and low‐cost sensing platforms. RESULTS Here we demonstrate the fabrication of a highly reproducible laser‐scribed graphitic electrode (LSE) on a polyimide (Kapton) film using a simple, do‐it‐yourself laser engraving system equipped with a 405 nm wavelength laser. Copper nanostructures were deposited onto an electrode surface via the electrodeposition process. The developed three‐dimensional graphitic electrodes modified by nano copper/copper oxide species (LSE‐Cu) were used for the detection of dopamine and glucose. Electrochemical studies of LSE‐Cu showed that in the presence of nano‐copper there is an apparent shift of the oxidation peaks of dopamine and ascorbic acid, allowing determination of dopamine without an interference effect, with an excellent sensitivity of 1321.54 μA L mmol −1 cm −2 . Furthermore, the LSE‐Cu sensor exhibited highly satisfying analytical performance towards glucose electro‐oxidation, with a reproducibility of 5.47% (RSD %). CONCLUSION We have demonstrated a simple design, fabrication and passivation route for the preparation of LSEs performing as biosensors. Such a cost‐effective and design‐flexible system is highly suitable for developing a biosensing platform towards various target analytes and further miniaturization of the electrode. © 2020 Society of Chemical Industry