We report for the first time the use of two live-cell imaging agents from the group of luminescent transition metal complexes (IRAZOLVE-MITO and REZOLVE-ER) as cathodoluminescent probes. This first experimental demonstration shows the application of both probes for the identification of cellular structures at the nanoscale and near the native state directly in the cryo-scanning electron microscope. This approach can potentially be applied to correlative and multimodal approaches and used to target specific regions within vitrified samples at low electron beam energies.

CRYTUR Spol S R O Turnov 511 01 Czech Republic

Faculty of Science Charles University Prague Prague 128 00 Czech Republic

Faculty of Science University of South Bohemia České Budějovice 37005 Czech Republic

Institute of Parasitology Biology Centre CAS České Budějovice 37005 Czech Republic

Institute of Scientific Instruments CAS Brno 612 000 Czech Republic

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