Isotopes of gallium

Last updated

Isotopes of gallium  (31Ga)
Main isotopes [1] Decay
abun­dance half-life (t1/2) mode pro­duct
66Ga synth 9.5 h β+ 66Zn
67Gasynth3.3 d ε 67Zn
68Gasynth1.2 hβ+ 68Zn
69Ga60.1% stable
70Gasynth21 min β− 70Ge
ε 70Zn
71Ga39.9%stable
72Gasynth14.1 hβ− 72Ge
73Gasynth4.9 hβ− 73Ge
Standard atomic weight Ar°(Ga)

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 60 to 89; 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.

Contents

Gallium-67 (half-life 3.3 days) is a gamma-emitting isotope (the gamma ray emitted immediately after electron capture) used in standard nuclear medical imaging, in procedures usually referred to as gallium scans. It is usually used as the free ion, Ga3+. It is the longest-lived radioisotope of gallium.

The shorter-lived gallium-68 (half-life 68 minutes) is a positron-emitting isotope generated in very small quantities from germanium-68 in gallium-68 generators or in much greater quantities by proton bombardment of 68Zn in low-energy medical cyclotrons, [4] [5] for use in a small minority of diagnostic PET scans. For this use, it is usually attached as a tracer to a carrier molecule (for example the somatostatin analogue DOTATOC), which gives the resulting radiopharmaceutical a different tissue-uptake specificity from the ionic 67Ga radioisotope normally used in standard gallium scans.

List of isotopes


Nuclide
[n 1] 		Z N Isotopic mass (Da) [6]
[n 2] [n 3] 		Half-life [1]
Decay
mode [1]
[n 4] 		Daughter
isotope
[n 5] 		Spin and
parity [1]
[n 6] [n 7] 		Natural abundance (mole fraction)
Excitation energyNormal proportion [1] Range of variation
60Ga312959.95750(22)#72.4(17) ms β+ (98.4%)60Zn(2+)
β+, p (1.6%)59Cu
β+, α? (<0.023%)56Ni
61Ga313060.949399(41)165.9(25) msβ+61Zn3/2−
β+, p? (<0.25%)60Cu
62Ga313161.94418964(68)116.122(21) msβ+62Zn0+
63Ga313262.9392942(14)32.4(5) sβ+63Zn3/2−
64Ga313363.9368404(15)2.627(12) minβ+64Zn0(+#)
64mGa42.85(8) keV21.9(7) μsIT64Ga(2+)
65Ga313464.93273442(85)15.133(28) minβ+65Zn3/2−
66Ga313565.9315898(12)9.304(8) hβ+66Zn0+
67Ga [n 8] 313666.9282023(13)3.2617(4) d EC 67Zn3/2−
68Ga [n 9] 313767.9279802(15)67.842(16) minβ+68Zn1+
69Ga313868.9255735(13)Stable3/2−0.60108(50)
70Ga313969.9260219(13)21.14(5) minβ− (99.59%)70Ge1+
EC (0.41%)70Zn
71Ga314070.92470255(87)Stable3/2−0.39892(50)
72Ga314171.92636745(88)14.025(10) hβ−72Ge3−
72mGa119.66(5) keV39.68(13) ms IT 72Ga(0+)
73Ga314272.9251747(18)4.86(3) hβ−73Ge1/2−
73mGa0.15(9) keV<200 msIT?73Ga3/2−
β−73Ge
74Ga314373.9269457(32)8.12(12) minβ−74Ge(3−)
74mGa59.571(14) keV9.5(10) sIT (>75%)74Ga(0)(+#)
β−? (<25%)74Ge
75Ga314474.92650448(72)126(2) sβ−75Ge3/2−
76Ga314575.9288276(21)30.6(6) sβ−76Ge2−
77Ga314676.9291543(26)13.2(2) sβ−77mGe (88%)3/2−
77Ge (12%)
78Ga314777.9316109(11)5.09(5) sβ−78Ge2−
78mGa498.9(5) keV110(3) nsIT78Ga
79Ga314878.9328516(13)2.848(3) sβ− (99.911%)79Ge3/2−
β−, n (0.089%)78Ge
80Ga314979.9364208(31)1.9(1) sβ− (99.14%)80Ge6−
β−, n (.86%)79Ge
80mGa [n 10] 22.45(10) keV1.3(2) sβ−80Ge3−
β−, n?79Ge
IT80Ga
81Ga315080.9381338(35)1.217(5) sβ− (87.5%)81mGe5/2−
β−, n (12.5%)80Ge
82Ga315181.9431765(26)600(2) msβ− (78.8%)82Ge2−
β−, n (21.2%)81Ge
β−, 2n?80Ge
82mGa140.7(3) keV93.5(67) nsIT82Ga(4−)
83Ga315282.9471203(28)310.0(7) msβ−, n (85%)82Ge5/2−#
β− (15%)83Ge
β−, 2n?81Ge
84Ga315383.952663(32)97.6(12) msβ− (55%)84Ge0−#
β−, n (43%)83Ge
β−, 2n (1.6%)82Ge
85Ga315484.957333(40)95.3(10) msβ−, n (77%)84Ge(5/2−)
β− (22%)85Ge
β−, 2n (1.3%)83Ge
86Ga315585.96376(43)#49(2) msβ−, n (69%)85Ge
β−, 2n (16.2%)84Ge
β− (15%)86Ge
87Ga315686.96901(54)#29(4) msβ−, n (81%)84Ge5/2−#
β−, 2n (10.2%)85Ge
β− (9%)87Ge
88Ga [7] 315787.97596(54)#β−?88Ge
β−, n?87Ge
89Ga [7] 3158
This table header & footer:
  1. ↑ mGa – Excited nuclear isomer.
  2. ↑ ( ) – Uncertainty (1σ) is given in concise form in parentheses after the corresponding last digits.
  3. ↑ # – Atomic mass marked #: value and uncertainty derived not from purely experimental data, but at least partly from trends from the Mass Surface (TMS).
  4. ↑ Modes of decay:
    EC: Electron capture
    IT: Isomeric transition
    n: Neutron emission
    p: Proton emission
  5. ↑ Bold symbol as daughter – Daughter product is stable.
  6. ↑ ( ) spin value – Indicates spin with weak assignment arguments.
  7. ↑ # – Values marked # are not purely derived from experimental data, but at least partly from trends of neighboring nuclides (TNN).
  8. ↑ Deexcitation gamma used in medical imaging
  9. ↑ Medically useful radioisotope
  10. ↑ Order of ground state and isomer is uncertain.

Gallium-67

Gallium-67 (67
Ga
) has a half-life of 3.26 days and decays by electron capture and gamma emission (in de-excitation) to stable zinc-67. It is a radiopharmaceutical used in gallium scans (alternatively, the shorter-lived gallium-68 may be used). This gamma-emitting isotope is imaged by gamma camera.

Gallium-68

Gallium-68 (68
Ga
) is a positron emitter with a half-life of 68 minutes, decaying to stable zinc-68. It is a radiopharmaceutical, generated in situ from the electron capture of germanium-68 (half-life 271 days) owing to its short half-life. This positron-emitting isotope can be imaged efficiently by PET scan (see gallium scan); alternatively, the longer-lived gallium-67 may be used. Gallium-68 is only used as a positron emitting tag for a ligand which binds to certain tissues, such as DOTATOC, which is a somatostatin analogue useful for imaging neuroendocrine tumors. Gallium-68 DOTA scans are increasingly replacing octreotide scans (a type of indium-111 scan using octreotide as a somatostatin receptor ligand). The 68
Ga
 is bound to a chemical such as DOTATOC and the positrons it emits are imaged by PET-CT scan. Such scans are useful in locating neuroendocrine tumors and pancreatic cancer. [8] Thus, octreotide scanning for NET tumors is being increasingly replaced by gallium-68 DOTATOC scan. [9]

Related Research Articles

A radioactive tracer, radiotracer, or radioactive label is a synthetic derivative of a natural compound in which one or more atoms have been replaced by a radionuclide. By virtue of its radioactive decay, it can be used to explore the mechanism of chemical reactions by tracing the path that the radioisotope follows from reactants to products. Radiolabeling or radiotracing is thus the radioactive form of isotopic labeling. In biological contexts, experiments that use radioisotope tracers are sometimes called radioisotope feeding experiments.

<span class="mw-page-title-main">Isotopes of thallium</span>

Thallium (81Tl) has 41 isotopes with atomic masses that range from 176 to 216. 203Tl and 205Tl are the only stable isotopes and 204Tl is the most stable radioisotope with a half-life of 3.78 years. 207Tl, with a half-life of 4.77 minutes, has the longest half-life of naturally occurring Tl radioisotopes. All isotopes of thallium are either radioactive or observationally stable, meaning that they are predicted to be radioactive but no actual decay has been observed.

<span class="mw-page-title-main">Isotopes of iodine</span>

There are 40 known isotopes of iodine (53I) from 108I to 147I; all undergo radioactive decay except 127I, which is stable. Iodine is thus a monoisotopic element.

Indium (49In) consists of two primordial nuclides, with the most common (~ 95.7%) nuclide (115In) being measurably though weakly radioactive. Its spin-forbidden decay has a half-life of 4.41×1014 years, much longer than the currently accepted age of the Universe.

Technetium (43Tc) is one of the two elements with Z < 83 that have no stable isotopes; the other such element is promethium. It is primarily artificial, with only trace quantities existing in nature produced by spontaneous fission or neutron capture by molybdenum. The first isotopes to be synthesized were 97Tc and 99Tc in 1936, the first artificial element to be produced. The most stable radioisotopes are 97Tc, 98Tc, and 99Tc.

Naturally occurring zirconium (40Zr) is composed of four stable isotopes (of which one may in the future be found radioactive), and one very long-lived radioisotope (96Zr), a primordial nuclide that decays via double beta decay with an observed half-life of 2.0×1019 years; it can also undergo single beta decay, which is not yet observed, but the theoretically predicted value of t1/2 is 2.4×1020 years. The second most stable radioisotope is 93Zr, which has a half-life of 1.53 million years. Thirty other radioisotopes have been observed. All have half-lives less than a day except for 95Zr (64.02 days), 88Zr (83.4 days), and 89Zr (78.41 hours). The primary decay mode is electron capture for isotopes lighter than 92Zr, and the primary mode for heavier isotopes is beta decay.

Bromine (35Br) has two stable isotopes, 79Br and 81Br, and 35 known radioisotopes, the most stable of which is 77Br, with a half-life of 57.036 hours.

Germanium (32Ge) has five naturally occurring isotopes, 70Ge, 72Ge, 73Ge, 74Ge, and 76Ge. Of these, 76Ge is very slightly radioactive, decaying by double beta decay with a half-life of 1.78 × 1021 years (130 billion times the age of the universe).

Copper (29Cu) has two stable isotopes, 63Cu and 65Cu, along with 28 radioisotopes. The most stable radioisotope is 67Cu with a half-life of 61.83 hours. Most of the others 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−.

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).

Iodine-123 (123I) is a radioactive isotope of iodine used in nuclear medicine imaging, including single-photon emission computed tomography (SPECT) or SPECT/CT exams. The isotope's half-life is 13.2232 hours; the decay by electron capture to tellurium-123 emits gamma radiation with a predominant energy of 159 keV. In medical applications, the radiation is detected by a gamma camera. The isotope is typically applied as iodide-123, the anionic form.

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.

<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.

Indium-111 (111In) is a radioactive isotope of indium (In). It decays by electron capture to stable cadmium-111 with a half-life of 2.8 days. Indium-111 chloride (111InCl) solution is produced by proton irradiation of a cadmium target in a cyclotron, as recommended by International Atomic Energy Agency (IAEA). The former method is more commonly used as it results in a high level of radionuclide purity.

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.

A germanium-68/gallium-68 generator is a device used to extract the positron-emitting isotope 68Ga of gallium from a source of decaying germanium-68. The parent isotope 68Ge has a half-life of 271 days and can be easily utilized for in-hospital production of generator produced 68Ga. Its decay product gallium-68 is extracted and used for certain positron emission tomography nuclear medicine diagnostic procedures, where the radioisotope's relatively short half-life and emission of positrons for creation of 3-dimensional PET scans, are useful.

<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">Radiopharmaceutical</span> Pharmaceutical drug which emits radiation, used as a diagnostic or therapeutic agent

Radiopharmaceuticals, or medicinal radiocompounds, are a group of pharmaceutical drugs containing radioactive isotopes. Radiopharmaceuticals can be used as diagnostic and therapeutic agents. Radiopharmaceuticals emit radiation themselves, which is different from contrast media which absorb or alter external electromagnetism or ultrasound. Radiopharmacology is the branch of pharmacology that specializes in these agents.

<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).

References

  1. 1 2 3 4 5 Kondev, F. G.; Wang, M.; Huang, W. J.; Naimi, S.; Audi, G. (2021). "The NUBASE2020 evaluation of nuclear properties" (PDF). Chinese Physics C. 45 (3): 030001. doi:10.1088/1674-1137/abddae.
  2. ↑ "Standard Atomic Weights: Gallium". CIAAW. 1987.
  3. ↑ Prohaska, Thomas; Irrgeher, Johanna; Benefield, Jacqueline; Böhlke, John K.; Chesson, Lesley A.; Coplen, Tyler B.; Ding, Tiping; Dunn, Philip J. H.; Gröning, Manfred; Holden, Norman E.; Meijer, Harro A. J. (2022-05-04). "Standard atomic weights of the elements 2021 (IUPAC Technical Report)". Pure and Applied Chemistry. doi:10.1515/pac-2019-0603. ISSN   1365-3075.
  4. ↑ Kumlin, J; Dam, J; Langkjaer, N; Chua, C.J.; Borjian, S.; Kassaian, A; Hook, B; Zeisler, S; Schaffer, P; Helge, Thisgaard (October 2019). "Multi-Curie Production of Ga-68 on a Biomedical Cyclotron". Conference: EANM'19. Retrieved 13 December 2019.
  5. ↑ Thisgaard, Helge; Kumlin, Joel; Langkjær, Niels; Chua, Jansen; Hook, Brian; Jensen, Mikael; Kassaian, Amir; Zeisler, Stefan; Borjian, Sogol; Cross, Michael; Schaffer, Paul (2021-01-07). "Multi-curie production of gallium-68 on a biomedical cyclotron and automated radiolabelling of PSMA-11 and DOTATATE". EJNMMI Radiopharmacy and Chemistry. 6 (1): 1. doi: 10.1186/s41181-020-00114-9 . ISSN   2365-421X. PMC   7790954 . PMID   33411034.
  6. ↑ Wang, Meng; Huang, W.J.; Kondev, F.G.; Audi, G.; Naimi, S. (2021). "The AME 2020 atomic mass evaluation (II). Tables, graphs and references*". Chinese Physics C. 45 (3): 030003. doi:10.1088/1674-1137/abddaf.
  7. 1 2 Shimizu, Y.; Kubo, T.; Sumikama, T.; Fukuda, N.; Takeda, H.; Suzuki, H.; Ahn, D. S.; Inabe, N.; Kusaka, K.; Ohtake, M.; Yanagisawa, Y.; Yoshida, K.; Ichikawa, Y.; Isobe, T.; Otsu, H.; Sato, H.; Sonoda, T.; Murai, D.; Iwasa, N.; Imai, N.; Hirayama, Y.; Jeong, S. C.; Kimura, S.; Miyatake, H.; Mukai, M.; Kim, D. G.; Kim, E.; Yagi, A. (8 April 2024). "Production of new neutron-rich isotopes near the N = 60 isotones Ge 92 and As 93 by in-flight fission of a 345 MeV/nucleon U 238 beam". Physical Review C. 109 (4): 044313. doi:10.1103/PhysRevC.109.044313.
  8. ↑ Hofman, M.S.; Kong, G.; Neels, O.C.; Eu, P.; Hong, E.; Hicks, R.J. (2012). "High management impact of Ga-68 DOTATATE (GaTate) PET/CT for imaging neuroendocrine and other somatostatin expressing tumours". Journal of Medical Imaging and Radiation Oncology. 56 (1): 40–47. doi: 10.1111/j.1754-9485.2011.02327.x . PMID   22339744. S2CID   21843609.
  9. ↑ Scott, A, et al. (2018). "Management of Small Bowel Neuroendocrine Tumors". Journal of Oncology Practice. 14 (8): 471–482. doi:10.1200/JOP.18.00135. PMC   6091496 . PMID   30096273.
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.