A carbon dot-based fluorometric probe for oxytetracycline detection utilizing a Förster resonance energy transfer mechanism

A carbon dot (CD)-based fluorometric probe for oxytetracycline (OTC) detection utilizing a Förster resonance energy transfer (FRET) mechanism was firstly developed. Upon addition of OTC, the blue fluorescence of the CDs peaked at 405 nm was quickly quenched, with a new fluorescence peaked at 505 nm attributed to OTC was observed within 30 s. A visual fluorescent color change of the CDs solution from blue to green was discerned under a 365 nm UV light irradiation. The CDs displayed a high sensitivity and selectivity toward OTC with a low detection limit of 0.41 μM. Furthermore, the probe was applied to detect OTC in water, milk, and pork samples with a satisfied recovery.