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Metal-Based Imaging Agents

  1. Lynn C. Francesconi,
  2. Melchor V. Cantorias,
  3. Robertha C. Howell

Published Online: 15 MAR 2006

DOI: 10.1002/0470862106.ia273

Encyclopedia of Inorganic Chemistry

Encyclopedia of Inorganic Chemistry

How to Cite

Francesconi, L. C., Cantorias, M. V. and Howell, R. C. 2006. Metal-Based Imaging Agents. Encyclopedia of Inorganic Chemistry. .

Author Information

  1. Hunter College and the Graduate School of the City University of New York, New York, NY, USA

Publication History

  1. Published Online: 15 MAR 2006


Radiopharmaceuticals are drugs that contain a radionuclide and are routinely used for diagnosis and treatment of disease. This review discusses imaging agents that are useful for diagnosis using Single Photon Emission Computed Tomography (SPECT) and Positron Emission Tomography (PET). Moreover, this entry focuses on the growing class of metal-based imaging agents, wherein the radionuclide is a transition metal or posttransition metal. The most widely used radionuclide for radiopharmaceuticals is technetium-99m, 99mTc, owing its widespread availability from the parent–daughter generator and its excellent physical properties for imaging. The radionuclides 67Ga, 111In, 210Tl, 57Co, and 51Cr are used in the clinic as well. There are a number of radioisotopes, including 64Cu, 67Cu, 68Ga, that show promise for diagnostic purposes. An increased understanding of the coordination chemistry of 99mTc and other radiometals resulted in first-generation metal-essential imaging agents. This understanding of coordination chemistry is responsible for the introduction and development of targeted receptor-specific agents, many of which are in clinical trials and some of which are on the market.


  • radiopharmaceuticals;
  • radionuclide;
  • technetium;
  • gallium;
  • indium;
  • copper;
  • single photon emission computed tomography (SPECT);
  • positron emission tomography (PET);
  • receptor-specific imaging agents;
  • receptor-specific peptides;
  • tumor imaging