Journal of Radiopharmaceuticals and Molecular Probes (대한방사성의약품학회지)

Korean Society of Radiopharmaceuticals and Molecular Probes (대한방사성의약품학회)
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Chelators for 68Ga radiopharmaceuticals

  • Seelam, Sudhakara Reddy (Department of Nuclear Medicine, Institute of Radiation Medicine, Seoul National University College of Medicine) ;
  • Lee, Yun-Sang (Department of Nuclear Medicine, Institute of Radiation Medicine, Seoul National University College of Medicine) ;
  • Jeong, Jae Min (Department of Nuclear Medicine, Institute of Radiation Medicine, Seoul National University College of Medicine)
  • Received : 2016.03.28
  • Accepted : 2016.06.01
  • Published : 2016.06.30
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Abstract

$^{68}Ga$ is a promising radionuclide for positron emission tomography (PET). It is a generator-produced ($^{68}Ge/^{68}Ga$-generator) radionuclide with a half-life of 68 min. The employment of $^{68}Ga$ for basic research and clinical applications is growing exponentially. Bifunctional chelators (BFCs) that can be efficiently radiolabeled with $^{68}Ga$ to yield complexes with good in vivo stability are needed. Given the practical advantages of $^{68}Ga$ in PET applications, gallium complexes are gaining increasing attention in biomedical imaging. However, new $^{68}Ga$-labeled radiopharmaceuticals that can replace $^{18}F$-labeled agents like [$^{18}F$]fluorodeoxyglucose (FDG) are needed. The majority of $^{68}Ga$-labeled derivatives currently in use consist of peptide agents, but the development of other agents, such as amino acid or nitroimidazole derivatives and glycosylated human serum albumin, is being actively pursued in many laboratories. Thus, the availability of new $^{68}Ga$-labeled radiopharmaceuticals with high impact is expected in the near future. Here, we present an overview of the different new classes of chelators for application in molecular imaging using $^{68}Ga$ PET.

Keywords

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