Fluorometric detection of quinolones via AIE and FRET with terbium-doped carbon dots and copper nanoclusters

• Published in: Food chemistry 2025-02, Vol.465 (Pt 2), p.142076, Article 142076
• Main Authors: Ali, Ramadan, Alshaman, Reem, Albalawi, Abdullah S., Alsharif, Osama M., Hakami, Osama A., Alharthi, Hamzah Hussain, Jumah, Faisal F., Al-Qarni, Abdulrhman M., Albalawi, Naif S., Alashjaee, Meshari Saud, Aljohani, Faisal S., Alghuzawi, Abdulaziz M., Al-Atwi, Muath H., Alharbi, Abdullah H., El-Wekil, Mohamed M.
• Format: Article
• Language: English
• Subjects: Animals; Anti-Bacterial Agents - analysis; Anti-Bacterial Agents - chemistry; Blue and red emissions; Carbon - chemistry; Ciprofloxacin - analysis; Ciprofloxacin - chemistry; Copper - analysis; Copper - chemistry; Fluorescence detection; Fluorescence Resonance Energy Transfer; Fluorometry - methods; Humans; Metal Nanoparticles - chemistry; Milk - chemistry; Milk analysis; Quantum Dots - chemistry; Quinolones - analysis; Quinolones - chemistry; Ratiometric detection; Terbium - chemistry; Urine analysis
• ISSN: 0308-8146; 1873-7072; 1873-7072
• DOI: 10.1016/j.foodchem.2024.142076

Terbium and nitrogen co-doped carbon dots (Tb@N-CDs), combined with α-lipoic acid-functionalized copper nanoclusters (LA@CuNCs), were proposed for the ratiometric detection of quinolone (QA) antibiotics. In this system, Tb@N-CDs facilitate the aggregation of LA@CuNCs, enhancing its fluorescence emission at 670 nm via aggregation-induced emission enhancement (AIEE). Meanwhile, the fluorescence emission of Tb@N-CDs at 460 nm diminishes due to Förster resonance energy transfer (FRET). Upon the introduction of QA, the binding between Tb3+ ions and N-CDs weakens, disrupting both AIEE and FRET processes. This disruption results in a reduction in fluorescence emission at 670 nm and a concurrent increase at 460 nm. The fluorescence response ratio (F460/F670) increases with higher concentrations of ciprofloxacin (CFX), demonstrating a linear range from 0.008 to 120 μmol L−1 and LOD of 1.6 nmol L−1. The method successfully detected CFX in milk and urine samples, achieving recoveries between 97.7 % and 103.8 %, RSD of less than 3.79 %. •A novel fluorescent hybrid was proposed for sensing of quinolones.•The fluorescent probe is LA@CuNCs/Tb@N-CDs.•Tb@N-CDs enhanced the fluorescence of LA@CuNCs via AIE effect.•The fluorescence emission of Tb@N-CDs was decreased due to FRET.•Addition of quinolones hindered the AIE and FRET between Tb@N-CDs and LA@CuNCs.