Metal-Free P, N Co-Doped Carbon Nanozyme Array for Catecholamine Sensing

Discriminating catecholamines with both rapidity and precision poses a significant analytical challenge. A nanozyme-based sensor array addresses this challenge via machine-learning-deconvoluted cross-reactive response patterns. Herein, we developed metal-free P, N co-doped carbon nanozymes and constructed a colorimetric sensor array based on three pyrolysis temperatures, which generates unique fingerprint responses for distinct epinephrine (Ep), norepinephrine (NE), and dopamine (DA). The metal-free nature of the P, N co-doped carbon nanozymes offers superior biocompatibility, low toxicity, and good stability, rendering them highly attractive for catecholamine sensing in complex biological matrices. Moreover, the tunable electronic structure enabled by heteroatom doping provides cross-reactive recognition sites essential for array-based discrimination.