Single-precursor-derived carbon and nitrogen co-doped CuO nanozymes for colorimetric detection of tetracycline

). Tetracycline (TC) suppresses this process, resulting in a decreased color signal. Based on this effect, a colorimetric and smartphone-assisted method was developed for TC detection, showing a linear range of 1-40 µM with detection limits of 0.15 µM and 0.38 µM. This work provides a simple and effective strategy for nanozyme-based sensing.