Microchimica Acta

, 186:166 | Cite as

Nitrogen-doped carbon nanodots prepared from polyethylenimine for fluorometric determination of salivary uric acid

  • Wei-Cheng Wu
  • Hsin-Yi Tiffany Chen
  • Shih-Chi Lin
  • Hsin-Ying Chen
  • Fu-Rong Chen
  • Huan-Tsung ChangEmail author
  • Fan-Gang TsengEmail author
Original Paper


Stable and low-cost carbon dots (C-dots) were prepared from polyethylenimine (PEI) by a hydrothermal method. It is found that the fluorescence of the C-dots (best measured at excitation/emission wavelengths of 365/473 nm) is quenched by selective oxidation of surface PEI by periodate but recovers in the presence of uric acid (UA). It is assumed that this is due to the selective reduction of the nitrone groups to hydroxylamine groups by UA. The findings were used to design a fluorometric method for determination of UA that has a 2.3 nM detection limit. This is lower than that of reported fluorometric and enzymatic assays. The performance of the method has been validated by determination of UA in samples of human saliva. It is found that the results agree well with those obtained by a commercial UA assay.

Graphical abstract

Schematic presentation of the polyethylenimine (PEI) carbon nanodots (C-dots) as a fluorescent probe for uric acid. Their fluorescence is quenched by periodate (IO4) due to oxidative formation of nitrone groups, an subsequently restored due to reduction by uric acid (UA).


Antioxidant C-dots Hydrothermal synthesis Periodate Nitrone Uricase 



We would like to thanks the financial support from MOST, Taiwan by the project: 104-2221-E-007-072-MY3, 104-2321-B-007-003, 103-2321-B-007-004, 104-2113-M-002-008-MY3, 104-2923-M-002-006-MY3, 106-2622-M-002-001-CC2 and EXCELLENCE UNIVERSITY CENTER PROJECT FOR BIOMEDICAL TECHNOLOGY, NTHU, 2013-2016. This work was also financially supported by the Frontier Research Center on Fundamental and Applied Sciences of Matters, from The Featured Areas Research Center Program within the framework of the Higher Education Sprout Project by the Ministry of Education (MOE 107QR001I5), Taiwan.

Compliance with ethical standards

The author(s) declare that they have no competing interests.

Supplementary material

604_2019_3277_MOESM1_ESM.docx (781 kb)
ESM 1 (DOCX 780 kb)


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Copyright information

© Springer-Verlag GmbH Austria, part of Springer Nature 2019

Authors and Affiliations

  1. 1.Department of Engineering and System Science, Frontier Research Center on Fundamental and Applied Sciences of MattersNational Tsing Hua UniversityHsinchuTaiwan
  2. 2.Nano Science and Technology Program, Taiwan International Graduate ProgramAcademia SinicaTaipeiTaiwan
  3. 3.Department of ChemistryNational Taiwan UniversityTaipeiTaiwan
  4. 4.Department of ChemistryChung Yuan Christian UniversityTaoyuanTaiwan
  5. 5.Research Center for Applied SciencesAcademia SinicaTaipeiTaiwan

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