MXene/Au@Co bimetallic enzyme EC-SPR microfluidic sensing platform for on-chip in situ monitoring of H₂O₂ in living cells

In situ dynamic monitoring of living cells plays a crucial role in early tumor identification and disease treatment. Here, we developed an electrochemical surface plasmon resonance (SPR) microfluidic analysis system for monitoring of hydrogen peroxide (H₂O₂) release from cells on the gold sensing surface. The as-prepared sensor employs a MXene-based Au@Co bimetallic nanostructure, which simultaneously exhibits excellent optical properties and continuous catalytic efficacy. The outstanding electronic structure and high specific surface area significantly enhance the target recognition ability and promote rapid reaction. Its kinetics is well described by the Langmuir model. The system can achieve a low detection limit of 0.021 μM and high sensitivity for H₂O₂, and can effectively distinguish cancer cells from normal cells. This research brings new breakthroughs in the monitoring of H₂O₂ within living cells, offering potential applications in targeted cancer therapy and diagnostics. It paves new avenues for delving into the underlying mechanisms involved.