In this work we have created a new family of lanthanide-based molecular imaging agents that can be used for multiplex imaging in the second near-infrared window (NIR-II, 1000-1700 nm). NIR-II light is particularly interesting for non-invasive, real-time imaging and diagnosis of living organisms, as it is unaffected by the native fluorescence of biological tissues and fluids, and can penetrate through them. In addition, multiplex imaging enables the simultaneous, real-time visualization of several biological markers for even more precise diagnosis of diseases and a deeper understanding of biological processes. This new family of molecular imaging agents is based on an innovative design and combines the exceptional advantages of “metallacrowns” to emit NIR-II light with those of ruthenium complexes, which exhibit strong absorption in the visible range and effectively sensitize lanthanides. Using NIR-II imaging experiments, we have been able to demonstrate that four bands from three different lanthanides can be distinguished unambiguously due to their minimal overlap, while exhibiting sufficient intensity to be detected through a tissue-mimicking phantom.

Enabling Visible Light Sensitization of YbIII, NdIII and ErIII in Dimeric LnIII/GaIII Metallacrowns through Functionalization with RuII Complexes for NIR-II Multiplex Imaging
Codruţa C. Bădescu-Singureanu, Dr. Anton S. Nizovtsev, Prof. Dr. Vincent L. Pecoraro, Prof. Dr. Stéphane Petoud, Dr. Svetlana V. Eliseeva
Angewandte Chemie International Edition 2024
https://doi-org.inc.bib.cnrs.fr/10.1002/anie.202416101

This article was reported by CNRS Chimie on its website.