Technetium-based imaging agents

X-ray photoelectron spectroscopy of potential technetium-based Imaging agents... 

Technetium and rhenium coordination chemistry has actively developed in order to design materials as potential radiopharmaceuticals diagnostic imaging agents for technetium and potential therapeutic reagents based on rhenium. Continuous efforts are still applied to find efficient chelating systems for the [MO]3+ cores (M=Tc, Re). Thus several complexes with monodentate and... 

An alternative approach to cationic myocardial imaging agents has been the development of neutral seven-coordinate Tc(III) complexes based on 1,2-dioxime ligands (dioximeH2) with one end capped by a boronic acid derivative (19, 253). These complexes are generally referred to as BATOs (boronic acid adducts of technetium dioximes) and have the general structure [TcX(dioximeH)2(dioxime)BR ] (X = Cl, Br R = alkyl) shown in 18. 

The development of technetium agents for imaging the brain, heart and kidneys has prompted the study of a range of Tc(V) 0X0 complexes, many of which are square-based pyramidal and contain a tetradentate ligand, often a mixed S- and A -donor the oxo ligand occupies the apical site. Complexes 22.34 and 22.35 (in their Tc forms, see Boxes 2.3 and 22.7) are examples of radiopharmaceuticals used as kidney and brain imaging agents respectively, ... 

Here we will recall just two of the advances made in the field of radiopharmaceuticals over the last few years. One shining example of an organometallic pharmaceutical that has been successfully commercialized is technetium-99m sestamibi, a hexakis (aUcyhsocyanide) complex of Tc(I) 29 that has become the most important myocardial imaging agent. The success of this compound, known by its trade name Cardiohte , has inspired researchers to develop other Tc-based radiopharmaceuticals [193-197]. 

Bone imaging is based on increased blood flow and the metabolic activity of new bone formation when bone is damaged by disease or injury. Many technetium-labeled bone seeking agents have been introduced, e.g., Tc-methylene diphosphonate (99mTc-MDP), which has a low cost, easy preparation. 

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