[Ti]Ti-HOPOs: Potential Complexes for the Development of Ti PET Imaging Agents

Overview

Journal ACS Omega

Publisher American Chemical Society

Specialty Chemistry

Date 2025 Mar 3

PMID 40028061

Authors

Shefali Saini

N V S Dinesh K Bhupathiraju

Samith B Jayawardana

Michael D Phipps

Jason S Lewis

Lynn C Francesconi

Gayan B Wijeratne

Melissa A Deri

Suzanne E Lapi

Affiliations

Soon will be listed here.

Abstract

Titanium-45 (Ti) is a radionuclide with desirable physical characteristics for use in positron emission tomography (PET) imaging including a moderate half-life (3.08 h), decay by positron emission (85%), and low mean positron energy of 0.439 MeV. Despite these promising characteristics, the radiochemistry for Ti including the development of suitable bifunctional chelators is relatively unexplored compared to that of other radiometals. This work investigated three hydroxypyridinone compounds, viz., 3,2,3-(LI-1,2-HOPO) or C8-HOPO, 3,3,3-(LI-1,2-HOPO) or C9-HOPO, 3,4,3-(LI-1,2-HOPO) or C10-HOPO as potential chelators for Ti. Radiolabeling optimization, stability, and biodistribution results demonstrated C9-HOPO to be a promising chelator for Ti. In vivo evaluation of the [Ti]Ti-C9-HOPO complex indicated rapid clearance with no signs of decomplexation.

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