Synergistic antenna-effect-driven multi-channel ratiometric wearable sensor for visual on-site detection and accurate discrimination of fluoroquinolone analogs.

The misuse and overuse of fluoroquinolone antibiotics (FQs) pose a global threat, driving the need for effective detection methods. This study developed a multi-channel ratiometric sensor by integrating cadmium telluride quantum dots (CdTe QDs) and terbium-based coordination polymers for the detection and discrimination of FQs. The addition of enrofloxacin (ENR) triggers an antenna effect, enhancing green Tb(III) emission and reducing red CdTe QDs fluorescence, resulting in a distinct color change. Furthermore, a point-of-care testing system, comprising a smartphone detector and a wearable fingertip sensor, was constructed for rapid and real-time ENR detection, achieving high sensitivity with detection limits of 4.7 nM and 13.1 nM for spectrometer- and paper-based sensors, respectively. The practical applicability was demonstrated through satisfactory recoveries (91.7 %-110.7 %) in food samples, confirming its anti-interference capability. Finally, by expanding this platform into an array format, the sensor successfully differentiated ENR analogs, highlighting its broad potential for contaminant monitoring.