Lanthanide Complexes in Molecular Magnetic Resonance Imaging and Theranostics

Abstract

Lanthanide complexes have attracted much attention in the biomedical field, and today various imaging applications make use of their versatile magnetic and luminescence properties. In this minireview, we give insight into the mechanistic aspects that allow modulation of the relaxation or chemical exchange saturation transfer (CEST) features, and thus the magnetic resonance imaging (MRI) efficiency of paramagnetic lanthanide chelates in order to create agents that are capable of providing an MRI response as a function of a specific biomarker. We focus on the detection of neurotransmitters, enzymatic activities, and amyloid peptides. We also describe two selected theranostic strategies: 1) a novel approach directed at monitoring drug release from liponanoparticles and 2) molecular or nanoparticle probes for the MRI visualization of photosensitizer delivery in photodynamic therapy.

Nanomedicine Particles Associated With Chemical Exchange Saturation Transfer Contrast Agents in Biomedical Applications

“…Because nanotheranostics is highly interdisciplinary, involving fields including biomedicine, imaging, chemistry, pharmaceutical sciences, and nanotechnology, its development has been relatively slow compared to that of single diagnostic or medicinal agents (Figure 2) (Lammers et al, 2011). Nonetheless, metal-based nanotheranostic agents have been successfully used in pre-clinical and clinical research (Lacerda and Toth, 2017). For example, drug-loaded superparamagnetic NPs and Gd-or Mn-conjugated nanomedicine enable monitoring not only drug delivery but also drug release by observing the change in T 1 and T 2 /T * 2 relaxation times after the drugs were released (Choi et al, 2011;Liu et al, 2019;Ruan et al, 2019).…”

Silber‐ und Bronze‐Medaillen des CNRS 2018

“…Toth und ihre Gruppe entwerfen, synthetisieren und charakterisieren Metallkomplex‐Sonden für den kernspintomographischen Nachweis von Enzymaktivitäten, Neurotransmittern und Amyloidpeptiden sowie theranostische Substanzen. Sie berichtete in Chemistry—A European Journal über das relaxomatrische Verhalten von Koordinationspolymeren mit Gadolinium(III)‐Chelateinheiten, und ihr Kurzaufsatz über Lanthanoidkomplexe in Bildgebung und Theranostik war Titelbildbeitrag von ChemMedChem …”

CNRS Silver and Bronze Medals 2018

“…Toth and her group are interested in the design, synthesis, and characterization of probes based on metal complexes for applications in magnetic resonance imaging, including the detection of enzymatic activities, neurotransmitters, or amyloid peptides, as well as theranostic agents. She has reported in Chemistry—A European Journal on the relaxomatric behavior of coordination polymers containing gadolinium(III) chelates, and her Minireview on lanthanide complexes for imaging and theranostics was featured on a cover of ChemMedChem …”