Abstract
Hydrogen peroxide (H(2)O(2)) is a signaling molecule that has the capacity to control a variety of biological processes in organisms. Cancer cells release more H(2)O(2) during abnormal tumor growth. There has been a considerable amount of interest in utilizing H(2)O(2) as a biomarker for the diagnosis of cancer tissue. In this study, an electrochemical sensor for H(2)O(2) was constructed based on 3D reduced graphene oxide (rGO), MXene (Ti(3)C(2)), and multi-walled carbon nanotubes (MWCNTs) composite. Three-dimensional (3D) rGO-Ti(3)C(2)-MWCNTs sensor showed good linearity for H(2)O(2) in the ranges of 1-60 μM and 60 μM-9.77 mM at a working potential of -0.25 V, with sensitivities of 235.2 µA mM(-1) cm(-2) and 103.8 µA mM(-1) cm(-2), respectively, and a detection limit of 0.3 µM (S/N = 3). The sensor exhibited long-term stability, good repeatability, and outstanding immunity to interference. In addition, the modified electrode was employed to detect real-time H(2)O(2) release from cancer cells and cancer tissue ex vivo.