Development of Mn Labeled Trastuzumab for Extended Time Point PET Imaging of HER2.

Purpose: Due to their long circulation time in the blood, monoclonal antibodies (mAbs) such as trastuzumab, are usually radiolabeled with long-lived positron emitters for the development of agents for Positron Emission Tomography (PET) imaging. Manganese-52 (Mn, t = 5.6 d, β  = 29.

Improving the In Vivo Stability of [Mn]Mn(II) Complexes with 18-Membered Macrocyclic Chelators for PET Imaging.

We report the [Mn/Mn]Mn(II) complexes of the macrocyclic chelators PYAN [3,6,10,13-tetraaza-1,8(2,6)-dipyridinacyclotetradecaphane] and CHXPYAN [(4,4,10,10)-3,5,9,11-tetraaza-1,7(2,6)-dipyridina-4,10(1,2)-dicyclohexanacyclododecaphane]. The X-ray crystal structures of Mn-PYAN and Mn-CHXPYAN evidence distorted octahedral geometries through coordination of the nitrogen atoms of the macrocycles. Cyclic voltammetry studies evidence reversible processes due to the Mn(II)/Mn(III) pair, indicating that the complexes are resistant to oxidation.

Production and separation of Be for use in an ion source.

Beryllium-7 (Be) was created by proton irradiation of natural (B) and enriched (B) boron targets. The targets were dissolved in nitric acid, and the Be was separated from the bulk boron target material by cation-exchange chromatography. An average recovery of (99.

Titanium-45 (Ti) Radiochemistry and Applications in Molecular Imaging.

Molecular imaging is an important part of modern medicine which enables the non-invasive identification and characterization of diseases. With the advancement of radiochemistry and scanner technology, nuclear medicine is providing insight into efficient treatment options for individual patients. Titanium-45 (Ti) is a lesser-explored radionuclide that is garnering increasing interest for the development of positron emission tomography (PET) radiopharmaceuticals.

Evaluation of a novel hexadentate 1,2-hydroxypyridinone-based acyclic chelate, HOPO-O-C4, for Sc/Sc, Ga, and Ti radiopharmaceuticals.

Introduction: Chelators play a crucial role in the development of metal-based radiopharmaceuticals, and with the continued interest in Ga and increasing availability of new radiometals such as Sc/Sc and Ti, there is a growing demand for tailored chelators that can form stable complexes with these metals. This work reports the synthesis and characterization of a hexadentate tris-1,2-hydroxypyridonone chelator HOPO-O-C4 and its in vitro and in vivo evaluation with the above mentioned radiometals.

Methods: To investigate the affinity of HOPO-O-C4, macroscopic studies were performed with Sc, and Ga followed by DFT structural optimization of the Sc, Ga and Ti complexes.

Radiochemistry and In Vivo Imaging of [Ti]Ti-THP-PSMA.

Titanium-45 (Ti) is a radionuclide with excellent physical characteristics for use in positron emission tomography (PET) imaging, including a moderate half-life (3.08 h), decay by positron emission (85%), and a low mean positron energy of 0.439 MeV.

Chelation chemistry of manganese-52 for PET imaging applications.

Introduction: Due to its decay and chemical properties, interest in manganese-52 has increased for development of long-lived PET radiopharmaceuticals. Its long half-life of 5.6 days, low average positron energy (242 keV), and sufficient positron decay branching ratio make it suitable for radiolabeling macromolecules for investigating slow biological processes.

Optimized Methods for the Production of High-Purity Pb Using Electroplated Thallium Targets.

Pb is a surrogate imaging match for Pb. This elementally matched pair is emerging as a suitable pair for imaging and targeted radionuclide therapy in cancer care. Because of the half-life (51.

Sc-HOPO: A Potential Construct for Use in Radioscandium-Based Radiopharmaceuticals.

Three isotopes of scandium─Sc, Sc, and Sc─have attracted increasing attention as potential candidates for use in imaging and therapy, respectively, as well as for possible theranostic use as an elementally matched pair. Here, we present the octadentate chelator 3,4,3-(LI-1,2-HOPO) (or HOPO), an effective chelator for hard cations, as a potential ligand for use in radioscandium constructs with simple radiolabeling under mild conditions. HOPO forms a 1:1 Sc-HOPO complex that was fully characterized, both experimentally and theoretically.

A General Design Strategy Enabling the Synthesis of Hydrolysis-Resistant, Water-Stable Titanium(IV) Complexes.

Despite its prevalence in the environment, the chemistry of the Ti ion has long been relegated to organic solutions or hydrolyzed TiO polymorphs. A knowledge gap in stabilizing molecular Ti species in aqueous environments has prevented the use of this ion for various applications such as radioimaging, design of water-compatible metal-organic frameworks (MOFs), and aqueous-phase catalysis applications. Herein, we show a thorough thermodynamic screening of bidentate chelators with Ti in aqueous solution, as well as computational and structural analyses of key compounds.

The advanced role of carbon quantum dots in nanomedical applications.

Carbon quantum dots (CQDs) have emerged as a potential material in the diverse fields of biomedical applications due to their numerous advantageous properties including fluorescence, water solubility, biocompatibility, low toxicity, small size and ease of modification, inexpensive scale-up production, and versatile conjugation with other nanoparticles. Thus, CQDs became a preferable choice in various biomedical applications such as nanocarriers for drugs, therapeutic genes, photosensitizers, and antibacterial molecules. Further, their potentials have also been verified in multifunctional diagnostic platforms, cellular and bacterial bio-imaging, development of theranostics nanomedicine, etc.