Two-photon lanthanide bioprobes

For one decade we combined the intrinsic advantage of two-photon microscopy (NIR excitation, 3D resolution) with the unique photophysical properties of lanthanide (sharp bands, long lifetime) for bioimaging purposes.

In this context we reported several first proof-of concept experiments

• Two-photon cell imaging using a Ln complex (J.Am.Chem.Soc. 2008, 130, 1532)
• Two-photon multiplexing (Dalton Trans. 2015, 44, 4918)
• Two-photon time gated imaging (PSLIM) and lifetime imaging (TSLIM)
• Two-photon FRET experiment (Chem. Sci. 2014, 5, 3475)

Legend

In this context we developed tri-azacyclononane based complexes that appear to be extremely luminescent:

• In the case of Yb, we demonstrated the feasibility of in-depth imaging of strongly scattering thick tissue by two-photon scanning microscopy in an unprecedented NIR-to-NIR configuration, by the design of a macrocyclic ytterbium complex functionalized by a two-photon antenna (Angew. Chem. Int. Ed. 2012, 51, 6622).
• In the case of Eu, we reported in collaboration with Parker’s group ans CISbio Company the brightest Eu complex. (Chem. Commun. 2013, 49, 1600)
• In the case of Sm, we described the first Sm bioprobe for two-photon imaging (Chem. Eur. J. 2015, 21, 17757).

This project will continue in several directions.

1. Extension of game of Ln-based two photon bioprobes in order to develop a two-photon multiplexing imaging;
2. Functional two-photon bioprobes.

Collaboration with Drs A. Duperray, A. Grichine (Institute A. Bonniot, Grenoble), S. Brasselet (Institute Fresnel Marseille), G. Muller (San Jose University), Pr. Parker (Durham University, UK), Drs. L. Lamarque and J. Zwier (Cisbio), Dr. L. Guy (Axis 2).