Review Article | Published:

Contrast agents for molecular photoacoustic imaging

Nature Methods volume 13, pages 639650 (2016) | Download Citation

Abstract

Photoacoustic imaging (PAI) is an emerging tool that bridges the traditional depth limits of ballistic optical imaging and the resolution limits of diffuse optical imaging. Using the acoustic waves generated in response to the absorption of pulsed laser light, it provides noninvasive images of absorbed optical energy density at depths of several centimeters with a resolution of 100 μm. This versatile and scalable imaging modality has now shown potential for molecular imaging, which enables visualization of biological processes with systemically introduced contrast agents. Understanding the relative merits of the vast range of contrast agents available, from small-molecule dyes to gold and carbon nanostructures to liposome encapsulations, is a considerable challenge. Here we critically review the physical, chemical and biochemical characteristics of the existing photoacoustic contrast agents, highlighting key applications and present challenges for molecular PAI.

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Acknowledgements

We thank J. Baumberg (Department of Physics, University of Cambridge) for helpful discussions on gold nanoparticle LSPR. This work was supported by CRUK (Career Establishment Award no. C47594/A16267 to J.W. and S.E.B., Core Funding C14303/A17197 to J.W. and S.E.B.), the European Commission (CIG FP7-PEOPLE-2013-CIG-630729 to J.W. and S.E.B.), the EPSRC-CRUK Cancer Imaging Centre in Cambridge and Manchester (C197/A16465 to J.W. and S.E.B.), King's College London and University College London Comprehensive Cancer Imaging Centre Cancer Research UK & Engineering and Physical Sciences Research Council, in association with the Medical Research Council and the Department of Health, UK (P.B.), and the European Union (project FAMOS FP7 ICT, contract 317744 to P.B.).

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  1. Department of Physics, University of Cambridge, Cambridge, UK.

    • Judith Weber
    •  & Sarah E Bohndiek
  2. Cancer Research UK Cambridge Institute, University of Cambridge, Cambridge, UK.

    • Judith Weber
    •  & Sarah E Bohndiek
  3. Department of Medical Physics and Biomedical Engineering, University College London, London, UK.

    • Paul C Beard

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The authors declare no competing financial interests.

Corresponding authors

Correspondence to Paul C Beard or Sarah E Bohndiek.

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https://doi.org/10.1038/nmeth.3929

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