Evaluation of chelating agents based on pyridine-azacrown compounds HPATA, PATAM, and HPATPA for Ga and Lu.

In this article, we present the synthesis and characterization of three macrocyclic chelators, HPATA, PATAM, and HPATPA, based on a pyridine-azacrown compound. Their complexation with Ga and Lu has been thoroughly investigated using MALDI TOF MS, H NMR spectroscopy, radiolabeling studies, and experiments in vitro with fetal bovine serum and a 1000-fold molar excess of HEDTA. Our studies have shown that the chelators HPATA and HPATPA form complexes at room temperature with both radionuclides (RCY > 80 % and > 90 % for complexes with HPATA and HPATPA after 30 min, respectively).

Double-Armed 18- and 21-Membered Macrocycles as Potential Chelators for Lead and Bismuth Radiopharmaceuticals.

With increasing clinical applications and interest in targeted alpha therapy, there is growing interest in developing alternative chelating agents for [Pb]Pb and [Bi]Bi that exhibit rapid radiolabeling kinetics and kinetic inertness. Herein we report the synthesis and detailed investigation of diacetate and dipicolinate 18- and 21-membered macrocyclic chelators BADA-18, BADA-21, BADPA-18, and BADPA-21 for the complexation of Pb and Bi ions with potential use in the preparation of radiopharmaceuticals. The formation of mononuclear complexes was established by using ESI-mass spectrometry, and their stability constants were determined by potentiometric titration.

Assessing the biocompatibility and stability of CeO nanoparticle conjugates with azacrowns for use as radiopharmaceuticals.

The application of nanoparticles is promising for the purposes of nuclear medicine due to the possibilities of using them as vectors and transporters of radionuclides. In this study, we have successfully synthesised conjugates of CeO nanoparticles and azacrown ligands. Then, the radiolabelling conditions with radionuclides Zn, Sc and Bi were selected and the kinetic stability of the complexes in biologically significant media was evaluated.

Synthesis of new acyclic chelators H4aPyta and H6aPyha and their complexes with Cu, Ga, Y, and Bi.

In this article, we present the synthesis and characterization of new acyclic pyridine-containing polyaminocarboxylate ligands H4aPyta and H6aPyha, which differ in structural rigidity and the number of chelating groups. Their abilities to form complexes with Cu, Ga, Y, and Bi cations, as well as the stability of the complexes, were evaluated by potentiometric titration method, radiolabeling with the corresponding radionuclides, studies, mass spectrometry, and HPLC. The structures of the resulting complexes were determined using NMR spectroscopy and DFT calculations.

Novel candidate theranostic radiopharmaceutical based on strontium hexaferrite nanoparticles conjugated with azacrown ligand.

In this article, we report to the best of our knowledge the first modification of NPs with ligands for combined radiopharmaceuticals. Nanoparticles with suitable magnetic properties can be used both for diagnostics as a contrast for MRI and for therapy, including the insufficiently studied magneto-mechanical therapy. Strontium hexaferrite is one of the few hard-magnetic materials for which stable biocompatible colloidal solutions can be obtained.

CeO-Azacrown Conjugate as a Nanoplatform for Combined Radiopharmaceuticals.

This study is one of the first attempts to assess CeO nanoparticles as a nanoplatform for radiopharmaceuticals with radionuclides. The process of functionalization using a bifunctional azacrown ligand is described, and the resulting conjugates are characterized by IR and Raman spectroscopy. Their complexes with Bi show a high stability in medically relevant media, thus encouraging the further study of these conjugates in vivo as potential combined radiopharmaceuticals.