Ratiometric fluorescence sensor based on carbon quantum dots for hydrocortisone detection in food samples

Due to the prime self-calibration capability, dual emission fluorescence sensor can be utilized to accurately detect target analytes. Herein, the hydrothermal strategy was employed to construct dual emission carbon quantum dots (D-CQDs) via cyanazine and carbamazepine as materials. Interestingly, D-CQDs displayed two fluorescence emission peaks at 418 and 441 nm. Meanwhile, some excellent features could be observed, such as strong fluorescence, good water-solubility, and photo-stability. The as-developed D-CQDs could be successfully applied to detect sensitively and selectively hydrocortisone (HYD). Under the optimal sensing conditions, a working curve was developed between ln(F₀/F) and HYD amounts. The linear range was 0-140 μM with detection limit of 0.029 μM. The sensing mechanism was assigned to static quenching effect (SQE). Moreover, this promising platform was used successfully to determine HYD in food samples with satisfied recoveries of 93.37-103.87 %. The greenness assessments indicated that this platform possessed excellent ecological friendliness and sustainability.