2022

Cellular detection of a mitochondria targeted brominated vinyl triphenylamine optical probe (TP-Br) by X-ray fluorescence microscopy.

Sounderya Nagarajan, Florent Poyer, Laura Fourmois, Delphine Naud-Martin, Kadda Medjoubi, Andrea Somogyi, Gabrielle Schanne, Lucas Henry, Nicolas Delsuc, Clotilde Policar, Helene C Bertrand, Florence Mahuteau-Betzer (2022 Jan 25)

Chemistry (Weinheim an der Bergstrasse, Germany) : Accepted Article : DOI : 10.1002/chem.202104424

Triphenylamine (TP) derivatives such as two-branch cationic vinylbenzimidazolium triphenylamine  TP-2Bzim are promising turn-on fluorescent probes suitable for two-photon imaging, labelling mitochondria in live cells. Here, we designed two TP-2Bzim derivatives as bimodal probes suitable for X-ray fluorescence imaging. The conjugation of the TP core with a rhenium tricarbonyl moiety in the TP-RePyta probe altered the localisation in live cells from mitochondria to lysosomes. The introduction of bromine on the TP core generated the TP-Br probe retaining good photophysical properties and mitochondria labeling in live cells. The influence of calcium channels in the uptake of TP-Br was studied. Synchrotron Radiation X-ray Fluorescence (SXRF) imaging of bromine enabled the detection of TP-Br and suggested a negligible presence of the probe in an unbound state in the incubated cells, a crucial point in the development of these probes. This study paves the way towards the development of TP probes as specific organelle stainers suitable for SXRF imaging.