ZFIN ID: ZDB-PUB-201219-6
Fast In Vivo Imaging of SHG Nanoprobes with Multiphoton Light-Sheet Microscopy
Malkinson, G., Mahou, P., Chaudan, É., Gacoin, T., Sonay, A.Y., Pantazis, P., Beaurepaire, E., Supatto, W.
Date: 2020
Source: ACS photonics   7: 1036-1049 (Journal)
Registered Authors: Pantazis, Periklis (Laki)
Keywords: none
MeSH Terms: none
PubMed: 33335947 Full text @ ACS Photonics
Two-photon light-sheet microscopy (2P-SPIM) provides a unique combination of advantages for fast and deep fluorescence imaging in live tissues. Detecting coherent signals such as second-harmonic generation (SHG) in 2P-SPIM in addition to fluorescence would open further imaging opportunities. However, light-sheet microscopy involves an orthogonal configuration of illumination and detection that questions the ability to detect coherent signals. Indeed, coherent scattering from micron-sized structures occurs predominantly along the illumination beam. By contrast, point-like sources such as SHG nanocrystals can efficiently scatter light in multiple directions and be detected using the orthogonal geometry of a light-sheet microscope. This study investigates the suitability of SHG light-sheet microscopy (SHG-SPIM) for fast imaging of SHG nanoprobes. Parameters that govern the detection efficiency of KTiOPO4 and BaTiO3 nanocrystals using SHG-SPIM are investigated theoretically and experimentally. The effects of incident polarization, detection numerical aperture, nanocrystal rotational motion, and second-order susceptibility tensor symmetries on the detectability of SHG nanoprobes in this specific geometry are clarified. Guidelines for optimizing SHG-SPIM imaging are established, enabling fast in vivo light-sheet imaging combining SHG and two-photon excited fluorescence. Finally, microangiography was achieved in live zebrafish embryos by SHG imaging at up to 180 frames per second and single-particle tracking of SHG nanoprobes in the blood flow.