Copper-64

Last updated
Copper-64, 64Cu
General
Symbol 64Cu
Names copper-64, 64Cu, Cu-64
Protons (Z)29
Neutrons (N)35
Nuclide data
Half-life (t1/2)12.701±0.002 h
Isotope mass 63.929764 [1] Da
Decay products 64Ni
64Zn
Decay modes
Decay mode Decay energy (MeV)
Beta0.5787±0.0009 [2]
Positron0.6531±0.0002
Internal conversion1.34577±0.00016
Isotopes of copper
Complete table of nuclides

Copper-64 (64Cu) is a positron and beta emitting isotope of copper, with applications for molecular radiotherapy and positron emission tomography. Its unusually long half-life (12.7-hours) for a positron-emitting isotope makes it increasingly useful when attached to various ligands, for PET and PET-CT scanning.

Contents

Properties

64Cu has a half-life of 12.7 hours and decays 17.9% by positron emission to 64Ni, 39.0% by beta decay to 64Zn, 43.1% by electron capture to 64Ni, and 0.475% gamma radiation/internal conversion. These emissions are 0.579 MeV, 0.653 MeV and 1.35 MeV for beta minus, positron, and gamma respectively. [2]

The oxidation states of copper in biology are I and II since Cu3+ is too powerful to exist in biochemical systems. Furthermore, copper(I) exists as a strong complex in aqueous solution and is not often seen. Copper(II) forms mononuclear complexes that are paramagnetic and prefers ligands of sulfur and nitrogen. [3]

Copper is essential in the human body as both a catalyst and as part of enzymes. Copper is mainly involved in redox reactions throughout the body, but also plays a role in iron transportation in blood plasma.

Production

Copper-64 can be produced by several different reactions with the most common methods using either a reactor or a particle accelerator. Thermal neutrons can produce 64Cu in low specific activity (the number of decays per second per amount of substance) and low yield through the 63Cu(n,γ)64Cu reaction. At the University of Missouri Research Reactor Center (MURR) 64Cu was produced using high-energy neutrons via the 64Zn(n,p)64Cu nuclear reaction in high specific activity but low yield. Using a biomedical cyclotron the 64Ni(p,n)64Cu nuclear reaction can produce large quantities of the nuclide with high specific activity. [3]

Applications

As a positron emitter, 64Cu has been used to produce experimental and clinical radiopharmaceuticals for the imaging of a range of conditions. Its beta emissions also raise the possibility of therapeutic applications. Compared to typical PET radionuclides it has a relatively long half-life, which can be advantageous for therapy, and for imaging certain physiological processes. [4] [5] [6]

PET imaging

Bone metastases

Experimental preclinical work has shown that 64Cu linked to methanephosphonate functional groups has potential as a bone imaging agent. [7]

Neuroendocrine tumors (NETs)

Neuroendocrine tumors (NETs) are localised clinically using a range of DOTA based radiopharmaceuticals. For PET imaging these are typically Gallium-68 based. A commercial 64Cu-DOTA-TATE product has been FDA approved for localization of somatostatin receptor positive NETs since 2020. [8] [9]

Prostate cancer

The Bombesin peptide has been shown to be overexpressed in BB2 receptors in prostate cancer. CB-TE2A a stable chelation system for 64Cu was incorporated with Bombesin analogs for in vitro and in vivo studies of prostate cancer. PET-CT imagining studies showed that it underwent uptake into prostate tumor xenografts selectively with decreased uptake into non target tissues. Other preclinical studies have shown that by targeting the gastrin-releasing peptide receptor pancreatic and breast cancer can also be detected. [10]

Renal perfusion

Ethylglyoxal bis(thiosemicarbazone) (ETS) has potential utility as a PET radiopharmaceutical with the various isotopes of copper. 64Cu-ETS has been used for experimental preclinical myocardial, cerebral and tumor perfusion evaluations, with a linear relationship between the renal uptake and blood flow. Renal perfusion can also be evaluated with CT or MRI instead of PET, but with drawbacks: CT requires administration of potentially allergenic contrast agents. MRI avoids use of ionising radiation but is difficult to implement, and often suffers from motion artefacts. PET with 64Cu can offer quantitative measurements of renal perfusion. [11] [12]

Wilson’s disease

Wilson disease is a rare condition in which copper is retained excessively in the body. Toxic levels of copper can lead to organ failure and premature death. 64Cu has been used experimentally to study whole body retention of copper in subjects with this disease. The technique can also separate heterozygous carriers and homozygous normals. [13]

Cancer therapy

Cu-ATSM - copper(II) (diacetyl-bis (N4-methylthiosemicarbazone)) - is being studied as a possible cancer therapy. Copper-ATSM-3D-spacefill.png
Cu-ATSM – copper(II) (diacetyl-bis (N4-methylthiosemicarbazone)) – is being studied as a possible cancer therapy.

64Cu-ATSM (diacetyl-bis(N4-methylthiosemicarbazone)) has been shown to increase the survival time of tumor-bearing animals. Areas of low oxygen retention have been shown to be resistant to external beam radiotherapy because hypoxia reduces the lethal effects of ionizing radiation. 64Cu was believed to kill these cells because of its unique decay properties. In animal models having colorectal tumors with and without induced hypoxia, Cu-ATSM was preferentially taken up by hypoxic cells over normoxic cells. The results demonstrated that this compound increased survival of the tumor bearing hamsters compared with controls. [14]

See also

Related Research Articles

<span class="mw-page-title-main">Positron emission tomography</span> Medical imaging technique

Positron emission tomography (PET) is a functional imaging technique that uses radioactive substances known as radiotracers to visualize and measure changes in metabolic processes, and in other physiological activities including blood flow, regional chemical composition, and absorption. Different tracers are used for various imaging purposes, depending on the target process within the body.

<span class="mw-page-title-main">Single-photon emission computed tomography</span> Nuclear medicine tomographic imaging technique

Single-photon emission computed tomography is a nuclear medicine tomographic imaging technique using gamma rays. It is very similar to conventional nuclear medicine planar imaging using a gamma camera, but is able to provide true 3D information. This information is typically presented as cross-sectional slices through the patient, but can be freely reformatted or manipulated as required.

<span class="mw-page-title-main">Nuclear medicine</span> Medical specialty

Nuclear medicine or nucleology is a medical specialty involving the application of radioactive substances in the diagnosis and treatment of disease. Nuclear imaging, in a sense, is "radiology done inside out" because it records radiation emitted from within the body rather than radiation that is transmitted through the body from external sources like X-ray generators. In addition, nuclear medicine scans differ from radiology, as the emphasis is not on imaging anatomy, but on the function. For such reason, it is called a physiological imaging modality. Single photon emission computed tomography (SPECT) and positron emission tomography (PET) scans are the two most common imaging modalities in nuclear medicine.

<span class="mw-page-title-main">Scintigraphy</span> Diagnostic imaging test in nuclear medicine

Scintigraphy, also known as a gamma scan, is a diagnostic test in nuclear medicine, where radioisotopes attached to drugs that travel to a specific organ or tissue (radiopharmaceuticals) are taken internally and the emitted gamma radiation is captured by gamma cameras, which are external detectors that form two-dimensional images in a process similar to the capture of x-ray images. In contrast, SPECT and positron emission tomography (PET) form 3-dimensional images and are therefore classified as separate techniques from scintigraphy, although they also use gamma cameras to detect internal radiation. Scintigraphy is unlike a diagnostic X-ray where external radiation is passed through the body to form an image.

<span class="mw-page-title-main">Isotopes of iodine</span> Nuclides with atomic number of 53 but with different mass numbers

There are 37 known isotopes of iodine (53I) from 108I to 144I; all undergo radioactive decay except 127I, which is stable. Iodine is thus a monoisotopic element.

Natural gallium (31Ga) consists of a mixture of two stable isotopes: gallium-69 and gallium-71. Twenty-nine radioisotopes are known, all synthetic, with atomic masses ranging from 56 to 86; along with three nuclear isomers, 64mGa, 72mGa and 74mGa. Most of the isotopes with atomic mass numbers below 69 decay to isotopes of zinc, while most of the isotopes with masses above 71 decay to isotopes of germanium. Among them, the most commercially important radioisotopes are gallium-67 and gallium-68.

Copper (29Cu) has two stable isotopes, 63Cu and 65Cu, along with 27 radioisotopes. The most stable radioisotope is 67Cu with a half-life of 61.83 hours, while the least stable is 54Cu with a half-life of approximately 75 ns. Most have half-lives under a minute. Unstable copper isotopes with atomic masses below 63 tend to undergo β+ decay, while isotopes with atomic masses above 65 tend to undergo β− decay. 64Cu decays by both β+ and β−.

Fluorodeoxyglucose (<sup>18</sup>F) Chemical compound

[18F]Fluorodeoxyglucose (INN), or fluorodeoxyglucose F 18, also commonly called fluorodeoxyglucose and abbreviated [18F]FDG, 2-[18F]FDG or FDG, is a radiopharmaceutical, specifically a radiotracer, used in the medical imaging modality positron emission tomography (PET). Chemically, it is 2-deoxy-2-[18F]fluoro-D-glucose, a glucose analog, with the positron-emitting radionuclide fluorine-18 substituted for the normal hydroxyl group at the C-2 position in the glucose molecule.

<span class="mw-page-title-main">Fluorine-18</span> Isotope of fluorine emitting a positron

Fluorine-18 (18F) is a fluorine radioisotope which is an important source of positrons. It has a mass of 18.0009380(6) u and its half-life is 109.771(20) minutes. It decays by positron emission 96.7% of the time and electron capture 3.3% of the time. Both modes of decay yield stable oxygen-18.

A gallium scan is a type of nuclear medicine test that uses either a gallium-67 (67Ga) or gallium-68 (68Ga) radiopharmaceutical to obtain images of a specific type of tissue, or disease state of tissue. Gallium salts like gallium citrate and gallium nitrate may be used. The form of salt is not important, since it is the freely dissolved gallium ion Ga3+ which is active. Both 67Ga and 68Ga salts have similar uptake mechanisms. Gallium can also be used in other forms, for example 68Ga-PSMA is used for cancer imaging. The gamma emission of gallium-67 is imaged by a gamma camera, while the positron emission of gallium-68 is imaged by positron emission tomography (PET).

<span class="mw-page-title-main">Octreotide scan</span> Type of medical imaging

An octreotide scan is a type of SPECT scintigraphy used to find carcinoid, pancreatic neuroendocrine tumors, and to localize sarcoidosis. It is also called somatostatin receptor scintigraphy (SRS). Octreotide, a drug similar to somatostatin, is radiolabeled with indium-111, and is injected into a vein and travels through the bloodstream. The radioactive octreotide attaches to tumor cells that have receptors for somatostatin. A gamma camera detects the radioactive octreotide, and makes pictures showing where the tumor cells are in the body, typically by a SPECT technique. A technetium-99m based radiopharmaceutical kit is also available.

Nuclear medicine physicians, also called nuclear radiologists or simply nucleologists, are medical specialists that use tracers, usually radiopharmaceuticals, for diagnosis and therapy. Nuclear medicine procedures are the major clinical applications of molecular imaging and molecular therapy. In the United States, nuclear medicine physicians are certified by the American Board of Nuclear Medicine and the American Osteopathic Board of Nuclear Medicine.

Scandium-44 (44Sc) is a radioactive isotope of scandium that decays by positron emission to stable 44Ca with a half-life of 4.042 hours.

Preclinical imaging is the visualization of living animals for research purposes, such as drug development. Imaging modalities have long been crucial to the researcher in observing changes, either at the organ, tissue, cell, or molecular level, in animals responding to physiological or environmental changes. Imaging modalities that are non-invasive and in vivo have become especially important to study animal models longitudinally. Broadly speaking, these imaging systems can be categorized into primarily morphological/anatomical and primarily molecular imaging techniques. Techniques such as high-frequency micro-ultrasound, magnetic resonance imaging (MRI) and computed tomography (CT) are usually used for anatomical imaging, while optical imaging, positron emission tomography (PET), and single photon emission computed tomography (SPECT) are usually used for molecular visualizations.

<span class="mw-page-title-main">DOTA-TATE</span> Eight amino-acid long peptide covalently bonded to a DOTA chelator

DOTA-TATE is an eight amino acid long peptide, with a covalently bonded DOTA bifunctional chelator.

<span class="mw-page-title-main">FMISO</span> Chemical compound

18F-FMISO or fluoromisonidazole is a radiopharmaceutical used for PET imaging of hypoxia. It consists of a 2-nitroimidazole molecule labelled with the positron-emitter fluorine-18.

<span class="mw-page-title-main">Peptide receptor radionuclide therapy</span> Type of radiotherapy

Peptide receptor radionuclide therapy (PRRT) is a type of radionuclide therapy, using a radiopharmaceutical that targets peptide receptors to deliver localised treatment, typically for neuroendocrine tumours (NETs).

<span class="mw-page-title-main">Somatostatin inhibitor</span> Class of pharmaceuticals

Somatostatin receptor antagonists are a class of chemical compounds that work by imitating the structure of the neuropeptide somatostatin, which is an endogenous hormone found in the human body. The somatostatin receptors are G protein-coupled receptors. Somatostatin receptor subtypes in humans include sstr1, 2A, 2 B, 3, 4, and 5. While normally expressed in the gastrointestinal (GI) tract, pancreas, hypothalamus, and central nervous system (CNS), they are expressed in different types of tumours. The predominant subtype in cancer cells is the ssrt2 subtype, which is expressed in neuroblastomas, meningiomas, medulloblastomas, breast carcinomas, lymphomas, renal cell carcinomas, paragangliomas, small cell lung carcinomas, and hepatocellular carcinomas.

<span class="mw-page-title-main">CERN-MEDICIS</span>

CERN-MEDical Isotopes Collected from ISOLDE (MEDICIS) is a facility located in the Isotope Separator Online DEvice (ISOLDE) facility at CERN, designed to produce high-purity isotopes for developing the practice of patient diagnosis and treatment. The facility was initiated in 2010, with its first radioisotopes (terbium-155) produced on 12 December 2017.

References

  1. ↑ "Copper, isotope of mass 64". PubChem. National Center for Biotechnology Information . Retrieved 25 April 2021.
  2. 1 2 Bé, M.-M; Chisté, V; Dulieu, C; Mougeot, X; Chechev, V; Kuzmenko, N; Kondev, F; Luca, A; Galán, M; Nichols, A L; Lee, K B; Arinc, A; Pearce, A; Huang, X; Wang, B (2006). "Cu-64" (PDF). In Bé, M.-M (ed.). Table of radionuclides (Volume 6). Sèvres: BIPM. p. 13. ISBN   978-92-822-2242-3.
  3. 1 2 Welch, Michael; Redvanly, Carol S. (2003). Handbook of Radiopharmaceuticals : radiochemistry and applications. New York: Wiley. doi:10.1002/0470846380. ISBN   9780471495604. S2CID   94079329.
  4. ↑ IAEA (2016). Cyclotron Produced Radionuclides: Emerging Positron Emitters for Medical Applications: 64Cu and 124I. Vienna: International Atomic Energy Agency. ISBN   978-92-0-109615-9.
  5. ↑ Gutfilen, Bianca; Souza, Sergio AL; Valentini, Gianluca (2 October 2018). "Copper-64: a real theranostic agent". Drug Design, Development and Therapy. 12: 3235–3245. doi: 10.2147/DDDT.S170879 . PMC   6173185 . PMID   30323557.
  6. ↑ Zhou, Yeye; Li, Jihui; Xu, Xin; Zhao, Man; Zhang, Bin; Deng, Shengming; Wu, Yiwei (1 January 2019). "64 Cu-based Radiopharmaceuticals in Molecular Imaging". Technology in Cancer Research & Treatment. 18: 153303381983075. doi: 10.1177/1533033819830758 . PMC   6378420 . PMID   30764737.
  7. ↑ Sun, Xiankai; Wuest, Melinda; Kovacs, Zoltan; Sherry, Dean; Motekaitis, Ramunas; Wang, Zheng; Martell, Arthur; Welch, Michael; Anderson, Carolyn (1 January 2003). "In vivo behavior of copper-64-labeled methanephosphonate tetraaza macrocyclic ligands". Journal of Biological Inorganic Chemistry. 8 (1–2): 217–225. doi:10.1007/s00775-002-0408-5. PMID   12459917. S2CID   22225650.
  8. ↑ "DETECTNET". Drugs@FDA. Food and Drug Administration . Retrieved 25 April 2021.
  9. ↑ Eychenne, Romain; Bouvry, Christelle; Bourgeois, Mickael; Loyer, Pascal; Benoist, Eric; Lepareur, Nicolas (2 September 2020). "Overview of Radiolabeled Somatostatin Analogs for Cancer Imaging and Therapy". Molecules. 25 (17): 4012. doi: 10.3390/molecules25174012 . PMC   7504749 . PMID   32887456.
  10. ↑ Parry, Jesse J.; Andrews, Rebecca; Rogers, Buck E. (13 July 2006). "MicroPET Imaging of Breast Cancer Using Radiolabeled Bombesin Analogs Targeting the Gastrin-releasing Peptide Receptor". Breast Cancer Research and Treatment. 101 (2): 175–183. doi:10.1007/s10549-006-9287-8. PMID   16838112. S2CID   25579379.
  11. ↑ Green, Mark A.; Mathias, Carla J.; Willis, Lynn R.; Handa, Rajash K.; Lacy, Jeffrey L.; Miller, Michael A.; Hutchins, Gary D. (April 2007). "Assessment of Cu-ETS2 as a PET radiopharmaceutical for evaluation of regional renal perfusion". Nuclear Medicine and Biology. 34 (3): 247–255. doi:10.1016/j.nucmedbio.2007.01.002. PMID   17383574.
  12. ↑ Welch, Michael J.; Redvanly, Carol S. (2003). Handbook of Radiopharmaceuticals: Radiochemistry and Applications. John Wiley & Sons. p. 407. ISBN   978-0-471-49560-4.
  13. ↑ Reed, Emily; Lutsenko, Svetlana; Bandmann, Oliver (2018). "Animal models of Wilson disease". Journal of Neurochemistry. 146 (4): 356–373. doi: 10.1111/jnc.14323 . PMC   6107386 . PMID   29473169.
  14. ↑ Lewis, J. S.; Laforest, R.; Buettner, T. L.; Song, S.-K.; Fujibayashi, Y.; Connett, J. M.; Welch, M. J. (30 January 2001). "Copper-64-diacetyl-bis(N4-methylthiosemicarbazone): An agent for radiotherapy". Proceedings of the National Academy of Sciences. 98 (3): 1206–1211. Bibcode:2001PNAS...98.1206L. doi: 10.1073/pnas.98.3.1206 . PMC   14733 . PMID   11158618.
This page is based on this Wikipedia article
Text is available under the CC BY-SA 4.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.