One‐Second Surface Graphenization Strategy for Highly Sensitive Valrubicin Electrochemical Sensor

Abstract

AbstractWe report a novel one‐second strategy for the surface treatment of conventional graphite electrodes for the electrochemical detection of valrubicin, a potent chemotherapeutic agent used intravesically for the treatment of bladder cancer. The surface graphenization process enhances the surface area of the electrode and introduces surface defects and strain that increase its electrocatalytic activity and provides fast charge transfer pathways for an efficient redox process with excellent stability due to the direct connection with the core graphite electrode. The surface graphenized electrode is characterized using electron microscopy and Raman spectroscopy, and its electrochemical properties are studied using cyclic voltammetry and electrochemical impedance spectroscopy. A voltammetric method is developed for valrubicin detection using the surface graphenized electrode, optimized, and the electrochemical reduction mechanism is elucidated. A calibration curve is established with a wide linear range of 0.02–3 μM and a low limit of detection of 26.9 nM. Excellent reproducibility and stability are displayed and the clinical validity is demonstrated by analyzing valrubicin in human serum, achieving a high recovery of ≈90 %. The high performance and excellent sensitivity of the developed electrode show the significant impact of the surface graphenization strategy for further application in electrochemical sensing.