Mo2CTx MXene-based non-enzymatic electrochemical sensor for selective detection of hydrogen peroxide in colorectal cancer cells

Abstract

Accurate and real-time monitoring of hydrogen peroxide (H₂O₂) in biological environments is critical for understanding redox-regulated processes associated with cancer progression. In this study, we developed, for the first time, a novel non-enzymatic electrochemical sensor based on two-dimensional molybdenum carbide MXene (Mo₂CT_x) for the selective detection of H₂O₂, with particular importance in human cancer cell applications. The synthesized Mo₂CT_x MXene was broadly characterized to confirm its layered morphology, surface terminations, and structural integrity. When coated onto a glassy carbon electrode (GCE), the MXene-modified glassy carbon electrode (MX-GCE) exhibited excellent electrocatalytic activity toward H₂O₂ reduction at a low operating potential of −0.45 V. The MX-GCE demonstrated a linear response range from 0.49 to 78.3 µM with a low detection limit of 1.02 µM and a rapid response time of ∼2 s. Interference analysis indicated that the MX-GCE exhibited high selectivity for H₂O₂ in the presence of common biological interferents. The practical applicability of the sensor was validated through real sample analysis by monitoring of extracellular H₂O₂ generated by cancer cells upon ascorbic acid induced stimulation. These results established that the Mo₂CT_x MXene modified electrode could be used as a stable and effective sensing platform for H₂O₂ detection in complex biological environments. This new sensor will be useful for oxidative stress monitoring and cancer diagnostics.