Nano Research

, Volume 10, Issue 9, pp 3113–3123 | Cite as

Two-photon-excited near-infrared emissive carbon dots as multifunctional agents for fluorescence imaging and photothermal therapy

  • Minhuan Lan
  • Shaojing Zhao
  • Zhenyu Zhang
  • Li Yan
  • Liang Guo
  • Guangle Niu
  • Jinfeng Zhang
  • Junfang Zhao
  • Hongyan Zhang
  • Pengfei Wang
  • Guangyu Zhu
  • Chun-Sing Lee
  • Wenjun Zhang
Research Article


C dots (CDs) have shown great potential in bioimaging and phototherapy. However, it is challenging to manipulate their fluorescent properties and therapeutic efficacy to satisfy the requirements for clinic applications. In this study, we prepared S, Se-codoped CDs via a hydrothermal method and demonstrated that the doping resulted in excitation wavelength-independent near-infrared (NIR) emissions of the CDs, with peaks at 731 and 820 nm. Significantly, the CDs exhibited a photothermal conversion efficiency of ~58.2%, which is the highest reported value for C nanostructures and is comparable to that of Au nanostructures. Moreover, the CDs had a large two-photon absorption cross section (~30,045 GM), which allowed NIR emissions and the photothermal conversion of the CDs through the two-photon excitation (TPE) mechanism. In vitro and in vivo tests suggested that CDs can function as new multifunctional phototheranostic agents for the TPE fluorescence imaging and photothermal therapy of cancer cells.


carbon dots phototheranostic agent two-photon excitation NIR emission photothermal conversion 


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This work was supported by the General Research Fund of Hong Kong (No. 11338516), and the National Natural Science Foundation of China (Nos. 51572269 and 51672230).

Supplementary material

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Two-photon-excited near-infrared emissive carbon dots as multifunctional agents for fluorescence imaging and photothermal therapy


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Copyright information

© Tsinghua University Press and Springer-Verlag Berlin Heidelberg 2017

Authors and Affiliations

  • Minhuan Lan
    • 1
  • Shaojing Zhao
    • 1
  • Zhenyu Zhang
    • 1
  • Li Yan
    • 1
  • Liang Guo
    • 2
  • Guangle Niu
    • 2
  • Jinfeng Zhang
    • 1
  • Junfang Zhao
    • 2
  • Hongyan Zhang
    • 2
  • Pengfei Wang
    • 2
    • 3
  • Guangyu Zhu
    • 4
  • Chun-Sing Lee
    • 1
  • Wenjun Zhang
    • 1
  1. 1.Center of Super-Diamond and Advanced Films (COSDAF), Department of Physics and Materials ScienceCity University of Hong KongHong KongChina
  2. 2.Key Laboratory of Photochemical Conversion and Optoelectronic Materials, Technical Institute of Physics and ChemistryChinese Academy of SciencesBeijingChina
  3. 3.School of Future TechnologyUniversity of Chinese Academy of SciencesBeijingChina
  4. 4.Department of Biology and ChemistryCity University of Hong KongHong KongChina

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