NIR-driven ROS generation by carbon nitride heterojunctions enables selective detection of copper ions in whole blood

In O₂-involved photoelectrochemical (PEC) biosensing, the generation of highly oxidizing superoxide radicals often triggers non-selective reactions with small molecules, severely compromising detection selectivity. To address this, carbon nitride heterojunctions were constructed to regulate reactive oxygen species (ROS) generation. By leveraging the inherent reducibility of photogenerated electrons, free of superoxide radical interference, highly selective near-infrared (NIR)-driven Cu²⁺ detection in whole blood was achieved, offering a new paradigm to mitigate ROS interference in an O₂-rich PEC biosensing system.