One-pot synthesis of nitrogen-doped carbon dots for sensing of Co2+ and tetracycline antibiotics, biological imaging, and fluorescent inks

• Published in: Journal of nanoparticle research : an interdisciplinary forum for nanoscale science and technology 2022-02, Vol.24 (2), Article 44
• Main Authors: Cheng, Sijie, Zhang, Junqiu, Liu, Yaoming, Wang, Yingte, Xiao, Yanteng, Zhang, Yong
• Format: Article
• Language: English
• Subjects: Acetic acid; Aloe; Antibiotics; Biocompatibility; Carbon; Carbon dioxide; Carbon dots; Characterization and Evaluation of Materials; Chemistry and Materials Science; Chlortetracycline; Cobalt; Environmental monitoring; Ethylenediamine; Ethylenediaminetetraacetic acids; Excitation; Fluorescent indicators; Food safety; Inks; Inorganic Chemistry; Lasers; Materials Science; Medical imaging; Nanoparticles; Nanotechnology; Nitrogen; Optical Devices; Optics; Photonics; Physical Chemistry; Research Paper; Synthesis; Water analysis; Water sampling; Wavelength
• ISSN: 1388-0764; 1572-896X
• DOI: 10.1007/s11051-022-05398-3

Novel fluorescent nitrogen-doped carbon dots (N-CDs) derived from aloe vera and ethylenediamine were synthesized. The synthesized N-CDs emit bright blue fluorescence (λem = 450 nm) when the excitation wavelength is 370 nm. Owing to the obvious response to Co 2+ /tetracycline antibiotics (TCs), N-CDs can be designed as a “signal-off” fluorescent probe for sensitive detection of Co 2+ in water samples and TCs (taking chlortetracycline (CTC) as an example) in water/milk samples with linear ranges of 1.48–243 μM and 0.49–257 μM. The limit of detection (LOD) of Co 2+ and CTC are 39.3 nM and 17.7 nM (3σ/m). The recoveries of Co 2+ and CTC were 94.00–104.46% and 94.00–105.33%, respectively, which are in an acceptable range. Taking into consideration the masking effect of ethylenediaminetetraacetic acid (EDTA) to Co 2+ , the selective detection of CTC can be realized. Furthermore, owing to the outstanding biocompatibility and optical performance, N-CDs have also been applied in biological imaging and fluorescent ink. In conclusion, the prepared N-CDs are expected to be widely used in environmental monitoring, food safety, and disease diagnosis. Graphical abstract A simple hydrothermal method was designed to synthesize novel fluorescent nitrogen-doped carbon dots (N-CDs) derived from aloe vera and ethylenediamine. The synthesized N-CDs exhibit outstanding solubility, stability and preeminent biocompatibility. The optical excitation and emission wavelength of N-CDs are 370 nm and 450 nm. Interestingly, the prepared N-CDs showed obviously response to Co 2+ and tetracycline antibiotics (TCs), which can be utilized as a “signal-off” fluorescent probe for sensitive detection of Co 2+ in water samples and CTC in water/milk samples with linear ranges of 1.48-243 μM and 0.49-257 μM. The limits of detection (LOD) are 39.3 nM and 17.7 nM. Owing to the outstanding biocompatibility and optical performance, N-CDs have also been used in biological imaging and fluorescent ink.