• The Korean Journal of Nuclear Medicine
• /
• v.36 no.1
• /
• pp.8-18
• /
• 2002

Early and accurate diagnosis of tumors using positron omission tomography (PET) has been the focus of considerable interest due to its high metastasis and mortality rates at late detection. PET radiopharmaceuticals-which exhibit a high tumor-to-background uptake ratio, and appropriate metabolic characteristics, and pharmacokinetics-are attractive tools for tumor imaging. Tumor imaging by these radiopharmaceuticals are based on metabolic and receptor imaging. The former is based on accelerated metabolism in tumor tissue compared to normal tissue and the rate roughly corresponding to the rate of growth of tumors. Radiopharmaceuticals for this purpose include radiolabeled sugars, amino acids, and nucleosides which detect increased glucose utilization, protein synthesis, and DNA synthesis, respectively. Tumor receptor imaging is based on the proliferation of tumor cells regulated by many hormones and growth factors, which bind to the corresponding receptors and exhibit the biological responses Radiopharmaceuticals used to image the tumor receptor systems may be ligands for the specific receptors and antibodies for the growth factor receptors. Some antitumor agents have been labeled with radionuclides and used to study in vivo biodistribution and pharmacokinetics in humans. This overview describes typical PET radiopharmaceuticals used for tumor imaging based on their uptake mechanisms.

• Nuclear Medicine and Molecular Imaging
• /
• v.41 no.2
• /
• pp.118-131
• /
• 2007

Neurotransmitter imaging with radiopharmaceuticals plays major role for understanding of neurological and psychiatric disorders such as Parkinson's disease and depression. Radiopharmaceuticals for neurotransmitter imaging can be divided to dopamine transporter imaging radiopharmaceuticals and serotonin trnasporter imaging radiopharmaceuticals. Many kinds of new dopamine transporter imaging radiopharmcaeuticals has a tropane ring and they showed different biological properties according to the substituted functional group on tropane ring. After the first clinical trials with $[^{123}I]{\beta}-CIT$, alkyl chain substituent introduced to tropane ring amine to decrease time for imaging acquisition and to increase selectivity. From these results, $[^{123}I]PE2I$, [18F]FE-CNT, $[^{123}I]FP-CIT$ and $[^{18}F]FP-CIT$ were developed and they showed high uptake on the dopamine transporter rich regions and fast peak uptake equilibrium time within 4 hours after injection. $[^{11}C]McN$ 5652 was developed for serotonin trnasporter imaging but this compound showed slow kinetics and high background radioactivity. To overcome these problems, new diarylsulfide backbone derivatives such as ADAM, ODAM, AFM, and DASB were developed. In these candidates, $[^{11}C]AFM$ and $[^{11}C]DASB$ showed high binding affinity to serotonin transporter and fast in vivo kinetics. This paper gives an overview of current status on dopamine and serotonin transporter imaging radiopharmaceuitcals and the development of new lead compounds as potential radiopharmaceuticals by medicinal chemistry.

• Journal of Radiopharmaceuticals and Molecular Probes
• /
• v.4 no.1
• /
• pp.32-35
• /
• 2018

Since utilization of metal is attractive research area applicable to medical applications, several metals have been studied by many scientists. Zr-89 is known as one of important radioisotopes nowadays. Novel ligands for Zr-89 have been developed, and Zr-89-based radiopharmaceuticals have been employed for positron emission tomography (PET) study. In this highlight review, recent advances on Zr-89 utilization for radiophramaceuticals are illustrated.

• Proceedings of the Korean Nuclear Society Conference
• /
• 2005.05a
• /
• pp.944-945
• /
• 2005

• Journal of Radiopharmaceuticals and Molecular Probes
• /
• v.5 no.2
• /
• pp.129-134
• /
• 2019

Over a few decades, copper radioisotopes and their chelation chemistry for radiopharmaceuticals have played crucial role in the radiopharmaceutical science area. A variety of chelators have been required for their stable targeting ability in physiological conditions. For radiolabeling with copper-64 into biomolecules, thermodynamic stability, kinetic inertness, pH stability, and redox stability should be considered. In this regard, many researchers have attempted to develop the chelators that can bind with copper more tightly, rapidly and stably for copper radiolabeling. This review discusses the chemistry of copper, its suitable chelators and characteristics, while elucidating the evaluations of each chelator for radiolabeling.

• Journal of Radiopharmaceuticals and Molecular Probes
• /
• v.4 no.1
• /
• pp.22-25
• /
• 2018

Radiopharmaceuticals are used for diagnosis or therapy of diseases. According to the recent consensus nomenclature rules for radiopharmaceutical chemistry, specific activity is defined as the radioactivity per gram of radiolabeled compound and molar activity as the radioactivity per mole of radiolabeled compound. In this review, molar activity of radiopharmaceuticals is discussed in terms of its significance in nuclear imaging as well as its measurement methods.

• Proceedings of the Korean Nuclear Society Conference
• /
• 2005.05a
• /
• pp.946-947
• /
• 2005

• Journal of Radiopharmaceuticals and Molecular Probes
• /
• v.7 no.1
• /
• pp.11-21
• /
• 2021

Radiopharmaceuticals are constantly being studied in the field of tumor diagnosis and therapy. As a result, many patents have been registered related to the development of radiopharmaceutical therapy. In this study, effective patents related to radiology and nuclear medicine filed during the past 10 years were collected from various countries like Korea, United States, Japan, Europe etc., and the application trends and growth stages were analyzed through statistical analysis. From the analysis results of 47,991 patents related to radiology and nuclear medicine, only 6,268 registered patents were found valid, and 80% of those were related to radiopharmaceutical development. In addition, we analyzed the patent of major competitors and used them to analyze the trends in radioisotopes and medicinal research. Among these, all the top 10 major applicants have found to be concentrating on radiopharmaceutical development.

• Journal of Radiopharmaceuticals and Molecular Probes
• /
• v.8 no.2
• /
• pp.129-137
• /
• 2022

Bombesin has a high binding affinity to gastrin-releasing peptide receptor (GRPR) and can be used as a targeting ligand in GRPR-related cancers. Because GRPR is overexpressed in prostate cancer, bombesin analogues have been investigated extensively for diagnosis and treatment of prostate cancer. In nuclear medicine, bombesin derivatives labeled with radiometals such as ^55/57Co, ⁶⁴Cu, ⁶⁸Ga, ^99mTc, and ¹⁷⁷Lu or radiohalogen such as ¹³¹I and ²¹¹At were developed as markers for early detection of tumors and theragnostic tool for cancer treatment. This review focuses on the introduction of bombesin-based radiopharmaceuticals that are studied in pre-clinical or clinical research.

• Nuclear Medicine and Molecular Imaging
• /
• v.43 no.3
• /
• pp.174-178
• /
• 2009

Many radiopharmaceuticals have been developed and wildy used in the imaging cardiac function. Myocardial perfusion imaging (MPI) is a well established noninvasive method of assessing coronary blood flow and has been widely used in patients diagnosed or suspected with coronary artery diseases. The innovation of radiopharmaceuticals used in the cardiac imaging is one of the most important contributors to the development of nuclear cardiology. Thallium-201 and various technetium-99m agents have been globally used for myocardial perfusion SPEG, and N-13 ammonia (13NH3), rubidium-82 (82Rb), 0-15 water (H2150) for myocardial perfusion PET. As well as the cardiac perfusion studies, new radiopharmaceuticals that visualize fat metabolism or receptors of the sympathetic nervous system have successfully been applied to clinical practice. Useful information can be obtained for diagnosing coronary artery disease, evaluating patients' condition, or assessing therapeutic effects. In this review, we describe the characteristics and clinical usefulness of radiopharmaceuticals used for cardiac SPEG and PET.