Novel N-doped carbon dots derived from citric acid and urea: fluorescent sensing for determination of metronidazole and cytotoxicity studies
Haiyan Qi, Lixin Qiu, Xiaohong Zhang, Tonghui Yi, Jing Jing, Rokayya Sami, Sitah Alanazi, Zahrah Alqahtani, Mahmood D. Aljabri, Mohammed M. Rahman
Abstract
Blue emitting nitrogen-doped carbon dots were synthesized using citric acid and urea through the hydrothermal method, and the fluorescence quantum yield was 35.08%. We discovered that N-CDs featured excellent robust fluorescence stability and chemical resistance. For metronidazole detection, our N-CDs exhibited quick response time, high selectivity and sensitivity, and low cytotoxicity. Specifically, our N-CDs could detect metronidazole in the linear range of 0-179 μM, and the LOD was 0.25 μM. Furthermore, metronidazole efficaciously quenches the fluorescence of N-CDs, possibly owing to the inner filter effect. Lastly, we have employed our N-CDs to detect metronidazole in commercial metronidazole tablets with high accuracy. Overall, the newly prepared fluorescence sensor, N-CDs, demonstrated a huge potential to detect metronidazole in a simple, efficient, sensitive, and rapid manner.