A portable and versatile rGO-Co₃O₄-Pt nanocomposite-based electrochemical sensor for ex vivo and in vivo cardiac oxidative stress monitoring

The excessive production of reactive oxygen species (ROS) disrupts redox homeostasis, contributing to the development of cardiovascular diseases. Among ROS, hydrogen peroxide (H₂O₂) serves as a key mediator of oxidative signaling and a critical biomarker of cellular oxidative damage due to its relative stability and signaling relevance. However, current detection strategies for ROS and H₂O₂ often lack the necessary sensitivity, selectivity, and real-time responsiveness, underscoring the urgent need for advanced sensing platforms to support precision cardiovascular medicine. The research introduces a ROS detection based on reduced graphene oxide-cobalt oxide-platinum (rGO-Co₃O₄-Pt) nanocomposites for biological sample analysis. The nanocomposite platform enables H₂O₂ detection down to 160 nM, with linearity up to 2.50 μM. The platform showed acceptable analytical performance in terms of sensitivity, repeatability, and selectivity, which enabled both ex vivo and in vivo H₂O₂ monitoring. The method was validated in doxorubicin (DOX)-induced cardiotoxicity models using HL-1 cells and C57BL/6J mice, showing strong correlation with MTT-based ROS assays. The rGO-Co₃O₄-Pt nanocomposite improves portable analytical devices for real-world pharmacological applications. The technology enables real-time therapeutic monitoring while optimizing individualized dosing and expanding its applications to cancer treatment and diabetes management and neurological disorders.