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A phosphorescent probe for in vivo imaging in the second near-infrared window


In the second near-infrared spectral window (NIR-II; with wavelengths of 1,000–1,700 nm), in vivo fluorescence imaging can take advantage of reduced tissue autofluorescence and lower light absorption and scattering by tissue. Here, we report the development and in vivo application of a NIR-II phosphorescent probe that has lifetimes of hundreds of microseconds and a Stokes shift of 430 nm. The probe is made of glutathione-capped copper–indium–selenium nanotubes, and in acidic environments (pH 5.5–6.5) switches from displaying fluorescence to phosphorescence. In xenograft models of osteosarcoma and breast cancer, intravenous or intratumoral injections of the probe enabled phosphorescence imaging at signal-to-background ratios, spatial resolutions and sensitivities higher than NIR-II fluorescence imaging with polymer-stabilized copper–indium–sulfide nanorods. Phosphorescence imaging may offer superior imaging performance for a range of biomedical uses.

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Fig. 1: Characterizations of CISe nanotubes.
Fig. 2: Photophysical properties of CISe nanotubes.
Fig. 3: Possible mechanism of the generation of NIR-II phosphorescence.
Fig. 4: In vivo biosafety evaluation of CISe nanotubes.
Fig. 5: Ultrahigh tumour-specific imaging by NIR-II phosphorescence.
Fig. 6: Superior penetration depth and resolution of NIR-II phosphorescence imaging.

Data availability

The main data supporting the results of this study are available within the paper and its Supplementary Information. The raw and analysed datasets are available in Figshare at (ref. 29). Source data are provided with this paper.


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This work was supported by the National Natural Science Foundation of China (51803161, 51533007 and 61622117), National Key Research and Development Program of China (2017YFA0205200), Office of Science Biological and Environmental Research Program, US Department of Energy (DE-SC0008397) and National Cancer Institute Centers of Cancer Nanotechnology Excellence grant CCNE-TR U54 CA119367.

Author information




Z.C., B.C. and T.S. conceived of and designed the study, supervised the project and wrote the manuscript. B.C. performed all of the experiments. Z.H. and J.T. assisted with the design of the study and analysed the data. R.L. and H.L. assisted with the biosafety evaluation. D.L. and C.Q. helped with the animal imaging. Y.R. assisted with the in vitro studies. X.S. contributed to structural analysis by TEM. All authors discussed the results and commented on the manuscript.

Corresponding authors

Correspondence to Zhenhua Hu, Taolei Sun or Zhen Cheng.

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Competing interests

The authors declare no competing interests.

Additional information

Peer review information Nature Biomedical Engineering thanks Zhen Chao Dong and the other, anonymous, reviewer(s) for their contribution to the peer review of this work. Peer reviewer reports are available.

Publisher’s note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Supplementary information

Supplementary Information

Supplementary Methods, Discussion, Figs. 1–33, Tables 1–3, References and captions for Supplementary Videos 1–4.

Reporting Summary

Video 1

In vivo video-rate NIR-II intensity imaging of a nude mouse bearing 143B tumours, in lateral position at 24 h post-injection of CISe nanotubes.

Video 2

In vivo video-rate NIR-II intensity imaging of a nude mouse bearing 143B tumours, in supine position at 24 h post-injection of CISe nanotubes.

Video 3

In vivo video-rate NIR-II intensity imaging of a nude mouse bearing 143B tumours, in lateral position at 24 h post-injection of PEG-CIS nanorods.

Video 4

In vivo video-rate NIR-II intensity imaging of a nude mouse bearing 143B tumours, in supine position at 24 h post-injection of PEG-CIS nanorods.

Peer Review File

Source data

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Source Data Fig. 3

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Source Data Fig. 5

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Source Data Fig. 6

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Chang, B., Li, D., Ren, Y. et al. A phosphorescent probe for in vivo imaging in the second near-infrared window. Nat Biomed Eng (2021).

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