Isotopes of bromine

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.

Like the radioactive isotopes of iodine, radioisotopes of bromine, collectively radiobromine, can be used to label biomolecules for nuclear medicine; for example, the positron emitters 75Br and 76Br can be used for positron emission tomography. Radiobromine has the advantage that organobromides are more stable than analogous organoiodides, and that it is not uptaken by the thyroid like iodine.

List of isotopes

 * 68Br
 * style="text-align:right" | 35
 * style="text-align:right" | 33
 * 67.95836(28)#
 * ~35 ns
 * p?
 * 67Se
 * 3+#
 * 69Br
 * style="text-align:right" | 35
 * style="text-align:right" | 34
 * 68.950338(45)
 * <19 ns
 * p
 * 68Se
 * (5/2−)
 * rowspan=2|70Br
 * rowspan=2 style="text-align:right" | 35
 * rowspan=2 style="text-align:right" | 35
 * rowspan=2|69.944792(16)
 * rowspan=2|78.8(3) ms
 * β+
 * 70Se
 * rowspan=2|0+
 * rowspan=2|
 * rowspan=2|
 * β+, p?
 * 69As
 * rowspan=2 style="text-indent:1em" | 70mBr
 * rowspan=2 colspan="3" style="text-indent:2em" | 2292.3(8) keV
 * rowspan=2|2.16(5) s
 * β+
 * 70Se
 * rowspan=2|9+
 * rowspan=2|
 * rowspan=2|
 * β+, p?
 * 69As
 * 71Br
 * style="text-align:right" | 35
 * style="text-align:right" | 36
 * 70.9393422(58)
 * 21.4(6) s
 * β+
 * 71Se
 * (5/2)−
 * 72Br
 * style="text-align:right" | 35
 * style="text-align:right" | 37
 * 71.9365946(11)
 * 78.6(24) s
 * β+
 * 72Se
 * 1+
 * rowspan=2 style="text-indent:1em" | 72mBr
 * rowspan=2 colspan="3" style="text-indent:2em" | 100.76(15) keV
 * rowspan=2|10.6(3) s
 * IT
 * 72Br
 * rowspan=2|(3-)
 * rowspan=2|
 * rowspan=2|
 * β+?
 * 72Se
 * 73Br
 * style="text-align:right" | 35
 * style="text-align:right" | 38
 * 72.9316734(72)
 * 3.4(2) min
 * β+
 * 73Se
 * 1/2−
 * 74Br
 * style="text-align:right" | 35
 * style="text-align:right" | 39
 * 73.9299103(63)
 * 25.4(3) min
 * β+
 * 74Se
 * (0−)
 * style="text-indent:1em" | 74mBr
 * colspan="3" style="text-indent:2em" | 13.58(21) keV
 * 46(2) min
 * β+
 * 74Se
 * 4+
 * rowspan=2|75Br
 * rowspan=2 style="text-align:right" | 35
 * rowspan=2 style="text-align:right" | 40
 * rowspan=2|74.9258106(46)
 * rowspan=2|96.7(13) min
 * β+ (76%)
 * 75Se
 * rowspan=2|3/2−
 * rowspan=2|
 * rowspan=2|
 * EC (24%)
 * 76Se
 * rowspan=2|76Br
 * rowspan=2 style="text-align:right" | 35
 * rowspan=2 style="text-align:right" | 41
 * rowspan=2|75.924542(10)
 * rowspan=2|16.2(2) h
 * β+ (57%)
 * 76Se
 * rowspan=2|1−
 * rowspan=2|
 * rowspan=2|
 * EC (43%)
 * 76Se
 * rowspan=2 style="text-indent:1em" | 76mBr
 * rowspan=2 colspan="3" style="text-indent:2em" | 102.58(3) keV
 * rowspan=2|1.31(2) s
 * IT (>99.4%)
 * 76Br
 * rowspan=2|(4)+
 * rowspan=2|
 * rowspan=2|
 * β+ (<0.6%)
 * 76Se
 * rowspan=2|77Br
 * rowspan=2 style="text-align:right" | 35
 * rowspan=2 style="text-align:right" | 42
 * rowspan=2|76.9213792(30)
 * rowspan=2|57.04(12) h
 * EC (99.3%)
 * 77Se
 * rowspan=2|3/2−
 * rowspan=2|
 * rowspan=2|
 * β+ (0.7%)
 * 77Se
 * style="text-indent:1em" | 77mBr
 * colspan="3" style="text-indent:2em" | 105.86(8) keV
 * 4.28(10) min
 * IT
 * 77Br
 * 9/2+
 * rowspan=2|78Br
 * rowspan=2 style="text-align:right" | 35
 * rowspan=2 style="text-align:right" | 43
 * rowspan=2|77.9211459(38)
 * rowspan=2|6.45(4) min
 * β+ (>99.99%)
 * 78Se
 * rowspan=2|1+
 * rowspan=2|
 * rowspan=2|
 * β− (<0.01%)
 * 78Kr
 * style="text-indent:1em" | 78mBr
 * colspan="3" style="text-indent:2em" | 180.89(13) keV
 * 119.4(10) μs
 * IT
 * 78Br
 * (4+)
 * 79Br
 * style="text-align:right" | 35
 * style="text-align:right" | 44
 * 78.9183376(11)
 * colspan=3 align=center|Stable
 * 3/2−
 * 0.5065(9)
 * style="text-indent:1em" | 79mBr
 * colspan="3" style="text-indent:2em" | 207.61(9) keV
 * 4.85(4) s
 * IT
 * 79Br
 * 9/2+
 * rowspan=2|80Br
 * rowspan=2 style="text-align:right" | 35
 * rowspan=2 style="text-align:right" | 45
 * rowspan=2|79.9185298(11)
 * rowspan=2|17.68(2) min
 * β− (91.7%)
 * 80Kr
 * rowspan=2|1+
 * rowspan=2|
 * rowspan=2|
 * β+ (8.3%)
 * 80Se
 * style="text-indent:1em" | 80mBr
 * colspan="3" style="text-indent:2em" | 85.843(4) keV
 * 4.4205(8) h
 * IT
 * 80Br
 * 5−
 * 81Br
 * style="text-align:right" | 35
 * style="text-align:right" | 46
 * 80.9162882(10)
 * colspan=3 align=center|Stable
 * 3/2−
 * 0.4935(9)
 * style="text-indent:1em" | 81mBr
 * colspan="3" style="text-indent:2em" | 536.20(9) keV
 * 34.6(28) μs
 * IT
 * 81Br
 * 9/2+
 * 82Br
 * style="text-align:right" | 35
 * style="text-align:right" | 47
 * 81.9168018(10)
 * 35.282(7) h
 * β−
 * 82Kr
 * 5−
 * rowspan=2 style="text-indent:1em" | 82mBr
 * rowspan=2 colspan="3" style="text-indent:2em" | 45.9492(10) keV
 * rowspan=2|6.13(5) min
 * IT (97.6%)
 * 82Br
 * rowspan=2|2−
 * rowspan=2|
 * rowspan=2|
 * β− (2.4%)
 * 82Kr
 * 83Br
 * style="text-align:right" | 35
 * style="text-align:right" | 48
 * 82.9151753(41)
 * 2.374(4) h
 * β−
 * 83Kr
 * 3/2−
 * style="text-indent:1em" | 83mBr
 * colspan="3" style="text-indent:2em" | 3069.2(4) keV
 * 729(77) ns
 * IT
 * 83Br
 * (19/2−)
 * 84Br
 * style="text-align:right" | 35
 * style="text-align:right" | 49
 * 83.916496(28)
 * 31.76(8) min
 * β−
 * 84Kr
 * 2−
 * style="text-indent:1em" | 84m1
 * colspan="3" style="text-indent:2em" | 310(100) keV
 * 6.0(2) min
 * β−
 * 84Kr
 * (6)−
 * style="text-indent:1em" | 84m2Br
 * colspan="3" style="text-indent:2em" | 408.2(4) keV
 * <140 ns
 * IT
 * 84Br
 * 1+
 * 85Br
 * style="text-align:right" | 35
 * style="text-align:right" | 50
 * 84.9156458(33)
 * 2.90(6) min
 * β−
 * 85Kr
 * 3/2−
 * 86Br
 * style="text-align:right" | 35
 * style="text-align:right" | 51
 * 85.9188054(33)
 * 55.1(4) s
 * β−
 * 86Kr
 * (1−)
 * rowspan=2|87Br
 * rowspan=2 style="text-align:right" | 35
 * rowspan=2 style="text-align:right" | 52
 * rowspan=2|86.9206740(34)
 * rowspan=2|55.68(12) s
 * β− (97.40%)
 * 87Kr
 * rowspan=2|5/2−
 * rowspan=2|
 * rowspan=2|
 * β−, n (2.60%)
 * 86Kr
 * rowspan=2|88Br
 * rowspan=2 style="text-align:right" | 35
 * rowspan=2 style="text-align:right" | 53
 * rowspan=2|87.9240833(34)
 * rowspan=2|16.34(8) s
 * β− (93.42%)
 * 88Kr
 * rowspan=2|(1−)
 * rowspan=2|
 * rowspan=2|
 * β−, n (6.58%)
 * 87Kr
 * style="text-indent:1em" | 88mBr
 * colspan="3" style="text-indent:2em" | 270.17(11) keV
 * 5.51(4) μs
 * IT
 * 88Br
 * (4−)
 * rowspan=2|89Br
 * rowspan=2 style="text-align:right" | 35
 * rowspan=2 style="text-align:right" | 54
 * rowspan=2|88.9267046(35)
 * rowspan=2|4.357(22) s
 * β− (86.2%)
 * 89Kr
 * rowspan=2|(3/2−, 5/2−)
 * rowspan=2|
 * rowspan=2|
 * β−, n (13.8%)
 * 88Kr
 * rowspan=2|90Br
 * rowspan=2 style="text-align:right" | 35
 * rowspan=2 style="text-align:right" | 55
 * rowspan=2|89.9312928(36)
 * rowspan=2|1.910(10) s
 * β− (74.7%)
 * 90Kr
 * rowspan=2|
 * rowspan=2|
 * rowspan=2|
 * β−, n (25.3%)
 * 89Kr
 * rowspan=2|91Br
 * rowspan=2 style="text-align:right" | 35
 * rowspan=2 style="text-align:right" | 56
 * rowspan=2|90.9343986(38)
 * rowspan=2|543(4) ms
 * β− (70.5%)
 * 91Kr
 * rowspan=2|5/2−#
 * rowspan=2|
 * rowspan=2|
 * β−, n (29.5%)
 * 90Kr
 * rowspan=3|92Br
 * rowspan=3 style="text-align:right" | 35
 * rowspan=3 style="text-align:right" | 57
 * rowspan=3|91.9396316(72)
 * rowspan=3|314(16) ms
 * β− (66.9%)
 * 92Kr
 * rowspan=3|(2−)
 * rowspan=3|
 * rowspan=3|
 * β−, n (33.1%)
 * 91Kr
 * β−, 2n?
 * 90Kr
 * style="text-indent:1em" | 92m1Br
 * colspan="3" style="text-indent:2em" | 662(1) keV
 * 88(8) ns
 * IT
 * 92Br
 * style="text-indent:1em" | 92m2Br
 * colspan="3" style="text-indent:2em" | 1138(1) keV
 * 85(10) ns
 * IT
 * 92Br
 * rowspan=3|93Br
 * rowspan=3 style="text-align:right" | 35
 * rowspan=3 style="text-align:right" | 58
 * rowspan=3|92.94322(46)
 * rowspan=3|152(8) ms
 * β−, n (64%)
 * 92Kr
 * rowspan=3|5/2−#
 * rowspan=3|
 * rowspan=3|
 * β− (36%)
 * 93Kr
 * β−, 2n?
 * 91Kr
 * rowspan=3|94Br
 * rowspan=3 style="text-align:right" | 35
 * rowspan=3 style="text-align:right" | 59
 * rowspan=3|93.94885(22)#
 * rowspan=3|70(20) ms
 * β−, n (68%)
 * 93Kr
 * rowspan=3|2−#
 * rowspan=3|
 * rowspan=3|
 * β− (32%)
 * 94Kr
 * β−, 2n?
 * 92Kr
 * style="text-indent:1em" | 94mBr
 * colspan="3" style="text-indent:2em" | 294.6(5) keV
 * 530(15) ns
 * IT
 * 94Br
 * rowspan=3|95Br
 * rowspan=3 style="text-align:right" | 35
 * rowspan=3 style="text-align:right" | 60
 * rowspan=3|94.95293(32)#
 * rowspan=3|80# ms [>300 ns]
 * β−?
 * 95Kr
 * rowspan=3|5/2−#
 * rowspan=3|
 * rowspan=3|
 * β−, n?
 * 94Kr
 * β−, 2n?
 * 93Kr
 * style="text-indent:1em" | 95mBr
 * colspan="3" style="text-indent:2em" | 537.9(5) keV
 * 6.8(10) μs
 * IT
 * 95Br
 * rowspan=3|96Br
 * rowspan=3 style="text-align:right" | 35
 * rowspan=3 style="text-align:right" | 61
 * rowspan=3|95.95898(32)#
 * rowspan=3|20# ms [>300 ns]
 * β−?
 * 96Kr
 * rowspan=3|
 * rowspan=3|
 * rowspan=3|
 * β−, n?
 * 95Kr
 * β−, 2n?
 * 94Kr
 * style="text-indent:1em" | 96mBr
 * colspan="3" style="text-indent:2em" | 311.5(5) keV
 * 3.0(9) μs
 * IT
 * 95Br
 * rowspan=3|97Br
 * rowspan=3 style="text-align:right" | 35
 * rowspan=3 style="text-align:right" | 62
 * rowspan=3|96.96350(43)#
 * rowspan=3|40# ms [>300 ns]
 * β−?
 * 97Kr
 * rowspan=3|5/2−#
 * rowspan=3|
 * rowspan=3|
 * β−, n?
 * 96Kr
 * β−, 2n?
 * 95Kr
 * rowspan=3|98Br
 * rowspan=3 style="text-align:right" | 35
 * rowspan=3 style="text-align:right" | 63
 * rowspan=3|97.96989(43)#
 * rowspan=3|15# ms [>400 ns]
 * β−?
 * 98Kr
 * rowspan=3|
 * rowspan=3|
 * rowspan=3|
 * β−, n?
 * 97Kr
 * β−, 2n?
 * 96Kr
 * 99Br
 * style="text-align:right" | 35
 * style="text-align:right" | 64
 * 100Br
 * style="text-align:right" | 35
 * style="text-align:right" | 65
 * 101Br
 * style="text-align:right" | 35
 * style="text-align:right" | 66
 * rowspan=3|93Br
 * rowspan=3 style="text-align:right" | 35
 * rowspan=3 style="text-align:right" | 58
 * rowspan=3|92.94322(46)
 * rowspan=3|152(8) ms
 * β−, n (64%)
 * 92Kr
 * rowspan=3|5/2−#
 * rowspan=3|
 * rowspan=3|
 * β− (36%)
 * 93Kr
 * β−, 2n?
 * 91Kr
 * rowspan=3|94Br
 * rowspan=3 style="text-align:right" | 35
 * rowspan=3 style="text-align:right" | 59
 * rowspan=3|93.94885(22)#
 * rowspan=3|70(20) ms
 * β−, n (68%)
 * 93Kr
 * rowspan=3|2−#
 * rowspan=3|
 * rowspan=3|
 * β− (32%)
 * 94Kr
 * β−, 2n?
 * 92Kr
 * style="text-indent:1em" | 94mBr
 * colspan="3" style="text-indent:2em" | 294.6(5) keV
 * 530(15) ns
 * IT
 * 94Br
 * rowspan=3|95Br
 * rowspan=3 style="text-align:right" | 35
 * rowspan=3 style="text-align:right" | 60
 * rowspan=3|94.95293(32)#
 * rowspan=3|80# ms [>300 ns]
 * β−?
 * 95Kr
 * rowspan=3|5/2−#
 * rowspan=3|
 * rowspan=3|
 * β−, n?
 * 94Kr
 * β−, 2n?
 * 93Kr
 * style="text-indent:1em" | 95mBr
 * colspan="3" style="text-indent:2em" | 537.9(5) keV
 * 6.8(10) μs
 * IT
 * 95Br
 * rowspan=3|96Br
 * rowspan=3 style="text-align:right" | 35
 * rowspan=3 style="text-align:right" | 61
 * rowspan=3|95.95898(32)#
 * rowspan=3|20# ms [>300 ns]
 * β−?
 * 96Kr
 * rowspan=3|
 * rowspan=3|
 * rowspan=3|
 * β−, n?
 * 95Kr
 * β−, 2n?
 * 94Kr
 * style="text-indent:1em" | 96mBr
 * colspan="3" style="text-indent:2em" | 311.5(5) keV
 * 3.0(9) μs
 * IT
 * 95Br
 * rowspan=3|97Br
 * rowspan=3 style="text-align:right" | 35
 * rowspan=3 style="text-align:right" | 62
 * rowspan=3|96.96350(43)#
 * rowspan=3|40# ms [>300 ns]
 * β−?
 * 97Kr
 * rowspan=3|5/2−#
 * rowspan=3|
 * rowspan=3|
 * β−, n?
 * 96Kr
 * β−, 2n?
 * 95Kr
 * rowspan=3|98Br
 * rowspan=3 style="text-align:right" | 35
 * rowspan=3 style="text-align:right" | 63
 * rowspan=3|97.96989(43)#
 * rowspan=3|15# ms [>400 ns]
 * β−?
 * 98Kr
 * rowspan=3|
 * rowspan=3|
 * rowspan=3|
 * β−, n?
 * 97Kr
 * β−, 2n?
 * 96Kr
 * 99Br
 * style="text-align:right" | 35
 * style="text-align:right" | 64
 * 100Br
 * style="text-align:right" | 35
 * style="text-align:right" | 65
 * 101Br
 * style="text-align:right" | 35
 * style="text-align:right" | 66
 * 96Kr
 * β−, 2n?
 * 95Kr
 * rowspan=3|98Br
 * rowspan=3 style="text-align:right" | 35
 * rowspan=3 style="text-align:right" | 63
 * rowspan=3|97.96989(43)#
 * rowspan=3|15# ms [>400 ns]
 * β−?
 * 98Kr
 * rowspan=3|
 * rowspan=3|
 * rowspan=3|
 * β−, n?
 * 97Kr
 * β−, 2n?
 * 96Kr
 * 99Br
 * style="text-align:right" | 35
 * style="text-align:right" | 64
 * 100Br
 * style="text-align:right" | 35
 * style="text-align:right" | 65
 * 101Br
 * style="text-align:right" | 35
 * style="text-align:right" | 66
 * 100Br
 * style="text-align:right" | 35
 * style="text-align:right" | 65
 * 101Br
 * style="text-align:right" | 35
 * style="text-align:right" | 66
 * 100Br
 * style="text-align:right" | 35
 * style="text-align:right" | 65
 * 101Br
 * style="text-align:right" | 35
 * style="text-align:right" | 66
 * 101Br
 * style="text-align:right" | 35
 * style="text-align:right" | 66
 * 101Br
 * style="text-align:right" | 35
 * style="text-align:right" | 66
 * 101Br
 * style="text-align:right" | 35
 * style="text-align:right" | 66

Bromine-75
Bromine-75 has a half-life of 97 minutes. This isotope undergoes β+ decay rather than electron capture about 76% of the time, so it was used for diagnosis and positron emission tomography (PET) in the 1980s. However, its decay product, selenium-75, produces secondary radioactivity with a longer half-life of 120.4 days.

Bromine-76
Bromine-76 has a half-life of 16.2 hours. While its decay is more energetic than 75Br and has lower yield of positrons (about 57% of decays), bromine-76 has been preferred in PET applications since the 1980s because of its longer half-life and easier synthesis, and because its decay product, 76Se, is not radioactive.

Bromine-77
Bromine-77 is the most stable radioisotope of bromine, with a half-life of 57 hours. Although β+ decay is possible for this isotope, about 99.3% of decays are by electron capture. Despite its complex emission spectrum, featuring strong gamma-ray emissions at 239, 297, 521, and 579 keV, 77Br was used in SPECT imaging in the 1970s, but except for longer-term tracing, this is no longer considered practical due to the difficult collimator requirements and the proximity of the 521 keV line to the 511 keV annihilation radiation related to the β+ decay. However, the auger electrons emitted during decay are well-suited for radiotherapy, and it can possibly be paired with the imaging-suited 76Br (produced as an impurity in common synthesis routes) for this application.