Here, we present ideas for electrochemical sensing based on rGO-Co₃O₄-Pt nanocomposite that was designed, characterized, and integrated onto a printed electrochemical strip for the detection of H₂O₂. As an important biomarker of oxidative stress, H₂O₂ is used to diagnose and keep an eye on many different diseases, as well as new threats connected to oxidative stress caused by DOX, especially in the heart. We then proceeded to test whether we could detect this oxidative stress by square wave voltammetry (SWV) detection in our device, as illustrated in Scheme 1. We monitored oxidative stress in real-time in both in vitro cell lines and in vivo mice models. This demonstrated a remarkably accurate ability to detect oxidative stress, surpassing the standard MTT method in confirming the benefits of the experiment. Systematic experiments in both animal models and in vitro setups validate all attributes of the device for continuous monitoring of oxidative stress changes. This cutting-edge technology opens new frontiers for early disease detection and personalized health monitoring.