Highly selective and sensitive detection of amaranth by using carbon dots-based nanosensor

• Published in: RSC advances 2019-08, Vol.9 (45), p.26315-2632
• Main Authors: Liu, Lizhen, Mi, Zhi, Li, Haihong, Li, Caiqing, Hu, Qin, Feng, Feng
• Format: Article
• Language: English
• Subjects: Amaranth; Carbon dots; Chemistry; Energy transfer; Fluorescence; Glycine; Nanosensors; Raw materials
• ISSN: 2046-2069; 2046-2069
• DOI: 10.1039/c9ra04494a

In this work, a novel fluorescence nanosensor for selective and sensitive determination of amaranth was constructed using carbon dots (C-dots). Water soluble C-dots with strong fluorescence were obtained by a simple microwave-assisted method using urea and glycine as raw materials. It was found that amaranth can efficiently and sensitively quench the C-dots fluorescence by the inner filter effect (IFE) and non-radiative energy transfer (NRET) mechanisms. The fluorescence quenching efficiency ( F 0 / F ) was strongly correlated with the concentration of amaranth in the 0.2-30 μM range. The detection limit (LOD) is 0.021 μM. There was no significant change in the fluorescence intensity of C-dots when other potentially interfering substances were present in the system. Our C-dots-based nanosensor was successfully utilized for the analysis of amaranth in drinks and showed rapid, sensitive and accurate responses. It indicates that the novel C-dots-based nanosensor has great potential in amaranth detection for real-life applications. Illustration of the synthesis of C-dots and the determination of amaranth based on the fluorescence quenching of C-dots.