Radiometals in Imaging and Therapy: Highlighting Two Decades of Research

Abstract

The present article highlights the important progress made in the last two decades in the fields of molecular imaging and radionuclide therapy. Advancements in radiometal-based positron emission tomography, single photon emission computerized tomography, and radionuclide therapy are illustrated in terms of their production routes and ease of radiolabeling. Applications in clinical diagnostic and radionuclide therapy are considered, including human studies under clinical trials; their current stages of clinical translations and findings are summarized. Because the metalloid astatine is used for imaging and radionuclide therapy, it is included in this review. In regard to radionuclide therapy, both beta-minus (β−) and alpha (α)-emitting radionuclides are discussed by highlighting their production routes, targeted radiopharmaceuticals, and current clinical translation stage.

Immuno-PET for Glioma Imaging: An Update

“…Notably, certain radionuclides traditionally used in clinical practice, such as 68 Ga and 18 F, have a too-short physical half-life, rendering them unsuitable for delayed imaging. In contrast, 89 Zr has shown more promising results due to its longer physical half-life [59]. In this context, it is crucial to emphasize that specific radiochemical approaches merit exploration to facilitate the labeling of mAbs with [ 68 Ga] or [ 18 F], particularly those involving in vivo bio-orthogonal reactions [60].…”

Towards the Stable Binding of Mercury: Synthesis and Functionalization of Dibenzyldiazabicyclononane Scaffolds

“…Bifunctional chelators are mostly considered for radiometals, which are able to encapsulate the radiometal by forming a complex and to provide a link to the tumor target vector molecule. [1][2][3][4] In contrast to other metals, organomercury compounds have a mandatory high water tolerance combined with the highest bond dissociation energies for Hg-C Ar -bonds. [32] However, acyclic organomercurials suffer from a significant hydrolysis.…”

“…The design of encapsulating systems based on chelating macromolecules to form stable radiometal conjugates continues to be an important part of radiopharmaceutical development for both diagnostic and therapeutic applications in nuclear medicine. [1][2][3][4] A critical aspect of radiometal-based radiopharmaceuticals is their stability in vivo. Unwanted release of the radiometal ion should be minimal in order to prevent offtarget accumulation in vivo.…”

177Lu-Labeled Iron Oxide Nanoparticles Functionalized with Doxorubicin and Bevacizumab as Nanobrachytherapy Agents against Breast Cancer

“…Although 177 Lu is still considered a “novel” non-conventional radionuclide, there is increasing interest in including it in cancer treatment in the next few years [ 1 ]. The effectiveness of 177 Lu radiopharmaceuticals has also been proven by the fact that Lutathera ® and, more recently, Pluvicto ® have been approved for the treatment of somatostatin-positive neuroendocrine and prostate tumors, respectively [ 2 ]. Most importantly, the beta particles emitted have a maximum energy of 497 keV, allowing for ideal penetration of soft tissue.…”