Reprogramming electron transfer at single-atom Pt sites to break the interference barrier in uric acid detection

Uric acid (UA) serves as a key biomarker for gout, cardiovascular disease, and kidney dysfunction, yet conventional detection methods relying on H 2 O 2 generation suffer from signal instability and interference from reductive species. Here, we report a uricase-like platinum-nitrogen-carbon nanozyme (Pt-N-C-NH 3 ) that redirects UA oxidation from a two-electron pathway toward a four-electron pathway. By decreasing graphitic nitrogen content, the local electronic microenvironment of platinum sites is modulated, which is associated with a lower calculated free-energy change for the rate-determining absorbed oxygen to absorbed hydroxyl transformation from 1.25 to 0.62 electron volts and thereby promoting oxygen reduction to water. Integrated into a microneedle sensing platform, UA is converted to allantoin for chemiluminescent readout. The sensor exhibits a wide linear range of 50.00 to 1000.00 μM and a detection limit of 15.86 μM, while maintaining 97.57% signal stability against reductive interferents. This work demonstrates that atomic-level coordination engineering enables programmable control over reaction pathways in artificial enzyme systems, thereby facilitating robust biosensing in complex biological environments.