Natural

gallium Gallium is a chemical element with the symbol Ga and atomic number 31. Discovered by French chemist Paul-Émile Lecoq de Boisbaudran in 1875, Gallium is in group 13 of the periodic table and is similar to the other metals of the group (aluminiu ...

(₃₁Ga) consists of a mixture of two stable

isotope Isotopes are two or more types of atoms that have the same atomic number (number of protons in their nuclei) and position in the periodic table (and hence belong to the same chemical element), and that differ in nucleon numbers (mass numbers) ...

s: gallium-69 and gallium-71. The most commercially important

radioisotope A radionuclide (radioactive nuclide, radioisotope or radioactive isotope) is a nuclide that has excess nuclear energy, making it unstable. This excess energy can be used in one of three ways: emitted from the nucleus as gamma radiation; transferr ...

s are gallium-67 and gallium-68. 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 scan 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 gal ...

s. 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 The positron or antielectron is the antiparticle or the antimatter counterpart of the electron. It has an electric charge of +1 '' e'', a spin of 1/2 (the same as the electron), and the same mass as an electron. When a positron collides ...

-emitting isotope generated in very small quantities from germanium-68 in

gallium-68 generator 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 p ...

s or in much greater quantities by proton bombardment of ⁶⁸Zn in low-energy medical

cyclotron A cyclotron is a type of particle accelerator invented by Ernest O. Lawrence in 1929–1930 at the University of California, Berkeley, and patented in 1932. Lawrence, Ernest O. ''Method and apparatus for the acceleration of ions'', filed: Janu ...

s, for use in a small minority of diagnostic

PET scan 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, r ...

s. For this use, it is usually attached as a tracer to a carrier molecule (for example the somatostatin analogue

DOTATOC Edotreotide (USAN, also known as (DOTA0- Phe1- Tyr3) octreotide, DOTA-TOC, DOTATOC) is a substance which, when bound to various radionuclides, is used in the treatment and diagnosis of certain types of cancer. When used therapeutically it is an ...

), which gives the resulting

radiopharmaceutical 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 ...

a different tissue-uptake specificity from the ionic ⁶⁷Ga radioisotope normally used in standard gallium scans.

List of isotopes

, - , ⁵⁶Ga , style="text-align:right" , 31 , style="text-align:right" , 25 , 55.99491(28)# , , p , ⁵⁵Zn , 3+# , , , - , ⁵⁷Ga , style="text-align:right" , 31 , style="text-align:right" , 26 , 56.98293(28)# , , p , ⁵⁶Zn , 1/2−# , , , - , ⁵⁸Ga , style="text-align:right" , 31 , style="text-align:right" , 27 , 57.97425(23)# , , p , ⁵⁷Zn , 2+# , , , - , ⁵⁹Ga , style="text-align:right" , 31 , style="text-align:right" , 28 , 58.96337(18)# , , p , ⁵⁸Zn , 3/2−# , , , - , ⁶⁰Ga , style="text-align:right" , 31 , style="text-align:right" , 29 , 59.95706(12)# , 70(10) ms , β⁺ , ⁶⁰Zn , (2+) , , , - , ⁶¹Ga , style="text-align:right" , 31 , style="text-align:right" , 30 , 60.94945(6) , 168(3) ms , β⁺ , ⁶¹Zn , 3/2− , , , - , ⁶²Ga , style="text-align:right" , 31 , style="text-align:right" , 31 , 61.944175(30) , 116.18(4) ms , β⁺ , ⁶²Zn , 0+ , , , - , ⁶³Ga , style="text-align:right" , 31 , style="text-align:right" , 32 , 62.9392942(14) , 32.4(5) s , β⁺ , ⁶³Zn , (3/2−) , , , - , ⁶⁴Ga , style="text-align:right" , 31 , style="text-align:right" , 33 , 63.9368387(22) , 2.627(12) min , β⁺ , ⁶⁴Zn , 0(+#) , , , - , style="text-indent:1em" , ^64mGa , colspan="3" style="text-indent:2em" , 42.85(8) keV , 21.9(7) μs , , , 2+ , , , - , ⁶⁵Ga , style="text-align:right" , 31 , style="text-align:right" , 34 , 64.9327348(9) , 15.2(2) min , β⁺ , ⁶⁵Zn , 3/2− , , , - , ⁶⁶Ga , style="text-align:right" , 31 , style="text-align:right" , 35 , 65.931589(3) , 9.49(7) h , β⁺ , ⁶⁶Zn , 0+ , , , - , ⁶⁷GaDeexcitation gamma used in

medical imaging Medical imaging is the technique and process of imaging the interior of a body for clinical analysis and medical intervention, as well as visual representation of the function of some organs or tissues (physiology). Medical imaging seeks to rev ...

, style="text-align:right" , 31 , style="text-align:right" , 36 , 66.9282017(14) , 3.2612(6) d , EC , ⁶⁷Zn , 3/2− , , , - , ⁶⁸Ga Medically useful

, style="text-align:right" , 31 , style="text-align:right" , 37 , 67.9279801(16) , 67.71(9) min , β⁺ , ⁶⁸Zn , 1+ , , , - , ⁶⁹Ga , style="text-align:right" , 31 , style="text-align:right" , 38 , 68.9255736(13) , colspan=3 align=center, Stable , 3/2− , 0.60108(9) , , - , rowspan=2, ⁷⁰Ga , rowspan=2 style="text-align:right" , 31 , rowspan=2 style="text-align:right" , 39 , rowspan=2, 69.9260220(13) , rowspan=2, 21.14(3) min , β⁻ (99.59%) , ⁷⁰Ge , rowspan=2, 1+ , rowspan=2, , rowspan=2, , - , EC (0.41%) , ⁷⁰Zn , - , ⁷¹Ga , style="text-align:right" , 31 , style="text-align:right" , 40 , 70.9247013(11) , colspan=3 align=center, Stable , 3/2− , 0.39892(9) , , - , ⁷²Ga , style="text-align:right" , 31 , style="text-align:right" , 41 , 71.9263663(11) , 14.095(3) h , β⁻ , ⁷²Ge , 3- , , , - , style="text-indent:1em" , ^72mGa , colspan="3" style="text-indent:2em" , 119.66(5) keV , 39.68(13) ms , IT , ⁷²Ga , (0+) , , , - , ⁷³Ga , style="text-align:right" , 31 , style="text-align:right" , 42 , 72.9251747(18) , 4.86(3) h , β⁻ , ⁷³Ge , 3/2− , , , - , ⁷⁴Ga , style="text-align:right" , 31 , style="text-align:right" , 43 , 73.926946(4) , 8.12(12) min , β⁻ , ⁷⁴Ge , (3-) , , , - , style="text-indent:1em" , ^74mGa , colspan="3" style="text-indent:2em" , 59.571(14) keV , 9.5(10) s , , , (0) , , , - , ⁷⁵Ga , style="text-align:right" , 31 , style="text-align:right" , 44 , 74.9265002(26) , 126(2) s , β⁻ , ⁷⁵Ge , (3/2)− , , , - , ⁷⁶Ga , style="text-align:right" , 31 , style="text-align:right" , 45 , 75.9288276(21) , 32.6(6) s , β⁻ , ''⁷⁶Ge'' , (2+,3+) , , , - , ⁷⁷Ga , style="text-align:right" , 31 , style="text-align:right" , 46 , 76.9291543(26) , 13.2(2) s , β⁻ , ⁷⁷Ge , (3/2−) , , , - , ⁷⁸Ga , style="text-align:right" , 31 , style="text-align:right" , 47 , 77.9316082(26) , 5.09(5) s , β⁻ , ⁷⁸Ge , (3+) , , , - , rowspan=2, ⁷⁹Ga , rowspan=2 style="text-align:right" , 31 , rowspan=2 style="text-align:right" , 48 , rowspan=2, 78.93289(11) , rowspan=2, 2.847(3) s , β⁻ (99.911%) , ^79mGe , rowspan=2, (3/2−)# , rowspan=2, , rowspan=2, , - , β⁻, n (.089%) , ⁷⁸Ge , - , rowspan=2, ⁸⁰Ga , rowspan=2 style="text-align:right" , 31 , rowspan=2 style="text-align:right" , 49 , rowspan=2, 79.93652(13) , rowspan=2, 1.697(11) s , β⁻ (99.11%) , ⁸⁰Ge , rowspan=2, (3) , rowspan=2, , rowspan=2, , - , β⁻, n (.89%) , ⁷⁹Ge , - , rowspan=2, ⁸¹Ga , rowspan=2 style="text-align:right" , 31 , rowspan=2 style="text-align:right" , 50 , rowspan=2, 80.93775(21) , rowspan=2, 1.217(5) s , β⁻ (88.11%) , ^81mGe , rowspan=2, (5/2−) , rowspan=2, , rowspan=2, , - , β⁻, n (11.89%) , ⁸⁰Ge , - , rowspan=2, ⁸²Ga , rowspan=2 style="text-align:right" , 31 , rowspan=2 style="text-align:right" , 51 , rowspan=2, 81.94299(32)# , rowspan=2, 0.599(2) s , β⁻ (78.5%) , ⁸²Ge , rowspan=2, (1,2,3) , rowspan=2, , rowspan=2, , - , β⁻, n (21.5%) , ⁸¹Ge , - , rowspan=2, ⁸³Ga , rowspan=2 style="text-align:right" , 31 , rowspan=2 style="text-align:right" , 52 , rowspan=2, 82.94698(32)# , rowspan=2, 308(1) ms , β⁻ (60%) , ⁸³Ge , rowspan=2, 3/2−# , rowspan=2, , rowspan=2, , - , β⁻, n (40%) , ⁸²Ge , - , rowspan=2, ⁸⁴Ga , rowspan=2 style="text-align:right" , 31 , rowspan=2 style="text-align:right" , 53 , rowspan=2, 83.95265(43)# , rowspan=2, 0.085(10) s , β⁻, n (70%) , ⁸³Ge , rowspan=2, , rowspan=2, , rowspan=2, , - , β⁻ (30%) , ⁸⁴Ge , - , ⁸⁵Ga , style="text-align:right" , 31 , style="text-align:right" , 54 , 84.95700(54)# , 50# ms 300 ns, , , 3/2−# , , , - , ⁸⁶Ga , style="text-align:right" , 31 , style="text-align:right" , 55 , 85.96312(86)# , 30# ms 300 ns, , , , , * Commercially available materials may have been subjected to an undisclosed or inadvertent isotopic fractionation. Substantial deviations from the given mass and composition can occur.

Gallium-67

Gallium-67 () has a half-life of 3.26 days and decays by

electron capture Electron capture (K-electron capture, also K-capture, or L-electron capture, L-capture) is a process in which the proton-rich nucleus of an electrically neutral atom absorbs an inner atomic electron, usually from the K or L electron shells. Thi ...

and

gamma emission A gamma ray, also known as gamma radiation (symbol γ or \gamma), is a penetrating form of electromagnetic radiation arising from the radioactive decay of atomic nuclei. It consists of the shortest wavelength electromagnetic waves, typically s ...

(in de-

excitation Excitation, excite, exciting, or excitement may refer to: * Excitation (magnetic), provided with an electrical generator or alternator * Excite Ballpark, located in San Jose, California * Excite (web portal), web portal owned by IAC * Electron exc ...

) to stable zinc-67. It is a

used in

s (alternatively, the shorter-lived gallium-68 may be used). This gamma-emitting isotope is imaged by gamma camera.

Gallium-68

Gallium-68 () is a positron emitter with a half-life of 68 minutes, decaying to stable zinc-68. It is a

, generated ''in situ'' from the

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

); 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

, which is a

somatostatin Somatostatin, also known as growth hormone-inhibiting hormone (GHIH) or by several other names, is a peptide hormone that regulates the endocrine system and affects neurotransmission and cell proliferation via interaction with G protein-couple ...

analogue useful for imaging

neuroendocrine tumors Neuroendocrine tumors (NETs) are neoplasms that arise from cells of the endocrine (hormonal) and nervous systems. They most commonly occur in the intestine, where they are often called carcinoid tumors, but they are also found in the pancreas, lun ...

. Gallium-68 DOTA scans are increasingly replacing octreotide scans (a type of

indium-111 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 (112Cd(p,2n) ...

scan using octreotide as a somatostatin receptor ligand). The is bound to a chemical such as

and the positrons it emits are imaged by

PET-CT Positron emission tomography–computed tomography (better known as PET-CT or PET/CT) is a nuclear medicine technique which combines, in a single gantry, a positron emission tomography (PET) scanner and an x-ray computed tomography (CT) scan ...

scan. Such scans are useful in locating

and

pancreatic cancer Pancreatic cancer arises when cell (biology), cells in the pancreas, a glandular organ behind the stomach, begin to multiply out of control and form a Neoplasm, mass. These cancerous cells have the malignant, ability to invade other parts of t ...

. Thus, octreotide scanning for NET tumors is being increasingly replaced by gallium-68 DOTATOC scan.

References

* Isotope masses from: ** * Isotopic compositions and standard atomic masses from: ** ** * Half-life, spin, and isomer data selected from the following sources. ** ** ** {{Navbox element isotopes Gallium

Gallium Gallium is a chemical element with the symbol Ga and atomic number 31. Discovered by French chemist Paul-Émile Lecoq de Boisbaudran in 1875, Gallium is in group 13 of the periodic table and is similar to the other metals of the group (aluminiu ...