Chinese Journal of Applied Chemistry ›› 2020, Vol. 37 ›› Issue (2): 227-234.DOI: 10.11944/j.issn.1000-0518.2020.02.190226

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Preparation of Nitrogen-Doped Carbon Dots for Highly Sensitive Detection of Amoxicillin

GONG Hui,KANG Yu,ZHANG Rong,REN Guodong,HOU Xiaoyu,ZHANG Min,LI Lihong,LIU Wen,WANG Haojiang,DIAO Haipeng()   

  1. College of Basic Medical,Shanxi Medical University,Taiyuan 03001,China
  • Received:2019-08-23 Accepted:2019-11-05 Online:2020-02-01 Published:2020-02-06
  • Contact: DIAO Haipeng
  • Supported by:
    Supported by the National Natural Science Foundation of China(No.21705104), the Key Research and Development Projects of Shanxi Province(No.201703D321015-2), and the Youth Science Foundation of Shanxi Province(No.201701D221064)


In this paper, the nitrogen-doped carbon dots (NCDs) were synthesized using the natural material dendrobe as the raw material by one-step hydrothermal method. The synthesized carbon dots were characterized by transmission electron microscopy(TEM), X-ray photoelectron spectroscopy(XPS), Fourier transform infrared (FTIR) spectroscopy, ultraviolet-visible(UV-Vis) absorption spectroscopy and photoluminescence spectroscopy (PL). The experiment results show that NCDs are spherical or quasi-spherical, uniformly dispersed with the size ranges from 1 to 5 nm, which can emit strong blue fluorescence. The surface of the synthesized NCDs is rich in water-soluble groups such as COOH, OH and NH2. The optimal excitation and emission wavelengths of NCDs are 350 and 435 nm, respectively. Meanwhile, the fluorescence emission has good luminescence stability. The fluorescence quantum yield of the carbon dots is as high as 29.19%. The effects of different substances on the fluorescence of NCDs were measured in a buffer solution with pH=7.4. Under the same conditions, only amoxicillin is able to significantly quench the fluorescence of NCDs, indicating the synthesized NCDs can selectively interact with amoxicillin. A sensitive sensor was constructed for detecting amoxicillin by changing the fluorescence intensity of carbon dots. The linear detection range for amoxicillin is from 2.6 to 30 μmol/L and the detection limit is 0.15 μmol/L.

Key words: nitrogen-doped carbon dots, high fluorescence quantum yield, fluorescence quenching, amoxicillin