Abstract：
A novel ratiometric fluorescence probe was developed for the determination of azithromycin (AZM) and sulfide ions based on the differential modulation of red emissive carbon dots (R-N@CDs) and blue emissive carbon dots (B-NS@CDs). The addition of sulfide anion selectively quenched the red emission of R-N@CDs while the blue emission of B-NS@CDs unaffected. Upon subsequent introduction of AZM to this R-N@CDs@sulfide system, the quenched red fluorescence was restored. Comprehensive characterization of the CDs was performed using UV-Vis, fluorescence, FTIR spectroscopy, XPS, and TEM. The proposed method exhibited excellent sensitivity and selectivity, with limits of detection of 0.33 µM for AZM and 0.21 µM for sulfide. Notably, this approach enabled direct detection of sulfide without requiring prior modulation of the CDs with metal ions, as is common in other reported methods. The ratiometric probe was successfully applied for the determination of AZM in biological fluids and sulfide in environmental water samples with high selectivity. This work presents the first fluorometric method for the detection of AZM in biological fluids.
摘要：
基于红色发射碳点（R-N@CD）和蓝色发射碳点（B-NS@CD）的差分调制，开发了一种新型比率荧光探针，用于测定阿奇霉素（AZM）和硫化物离子。硫化物阴离子的添加选择性地猝灭了R-N@CD的红色发射，而B-NS@CD的蓝色发射不受影响。在随后将AZM引入该R-N@CD@硫化物系统后，猝灭的红色荧光恢复。使用UV-Vis对CD进行了全面表征，荧光，FTIR光谱,XPS,和TEM。该方法具有良好的灵敏度和选择性,AZM的检出限为0.33µM，硫化物的检出限为0.21µM。值得注意的是,这种方法能够直接检测硫化物，而不需要预先用金属离子调制CD，这在其他报道的方法中很常见。该比例探针已成功用于生物流体中的AZM和环境水样中的硫化物的高选择性测定。这项工作提出了第一个用于检测生物流体中AZM的荧光法。
