Hubbry Logo
Isotopes of goldIsotopes of goldMain
Open search
Isotopes of gold
Community hub
Isotopes of gold
logo
7 pages, 0 posts
0 subscribers
Be the first to start a discussion here.
Be the first to start a discussion here.
Isotopes of gold
Isotopes of gold
Isotopes of gold
View on Wikipedia
from Wikipedia

Isotopes of gold (79Au)
Main isotopes[1] Decay
Isotope abun­dance half-life (t1/2) mode pro­duct
195Au synth 186.01 d ε 195Pt
196Au synth 6.165 d β+ 196Pt
β− 196Hg
197Au 100% stable
198Au synth 2.6946 d β− 198Hg
199Au synth 3.139 d β− 199Hg
Standard atomic weight Ar°(Au)

Gold (79Au) has one stable isotope, 197Au, and known radioisotopes ranging from 169Au to 210Au, with the most stable 195Au being the most stable with a half-life of 186.01 days, followed by 196Au at 6.165 days. Isotopes heavier than the stable mass number 197 generally decay by beta emission to mercury isotopes, while those lighter decay by electron capture to platinum isotopes or alpha emission to iridium isotopes; 196 decays both to platinum and to mercury. Of the meta states the most stable is 198m2Au at 2.27 days.

Gold is currently the heaviest monoisotopic element (and is also mononuclidic). Bismuth formerly held that distinction until alpha decay of the 209Bi isotope was observed. All isotopes of gold are either radioactive or, in the case of 197Au, observationally stable, meaning that 197Au is predicted to be radioactive but no actual decay has been observed.[4]

List of isotopes

[edit]


Nuclide
[n 1] 		Z N Isotopic mass (Da)[5]
[n 2][n 3] 		Half-life[1]
[n 4] 		Decay
mode[1]
[n 5] 		Daughter
isotope
[n 6][n 7] 		Spin and
parity[1]
[n 8][n 4] 		Isotopic
abundance
Excitation energy[n 4]
169Au[6] 79 90 168.99808(32)# 1.16+0.50
−0.47 μs 		p (~94%) 168Pt (11/2−)
α (~6%) 165mIr
170Au[7] 79 91 169.99602(22)# 286+50
−40 μs 		p (89%) 169Pt (2)−
α (11%) 166Ir
170mAu[7] 282(10) keV 617+50
−40 μs 		p (58%) 169Pt (9)+
α (42%) 166mIr
171Au[7] 79 92 170.991882(22) 22+3
−2 μs 		p 170Pt 1/2+
α? 167Ir
171mAu[7] 258(13) keV 1.09(3) ms α (66%) 167mIr 11/2−
p (34%) 170Pt
172Au 79 93 171.99000(6) 28(4) ms α (98%) 168Ir (2)−
p (2%) 171Pt
β+ 172Pt
172mAu[n 9] 160(250) keV 11.0(10) ms α 168Ir (9,10)+
p? 171Pt
173Au 79 94 172.986224(24) 25.5(8) ms α (86%) 169Ir (1/2+)
β+ (14%) 173Pt
173mAu 214(21) keV 12.2(1) ms α (89%) 169Ir (11/2−)
β+ (11%) 173Pt
174Au 79 95 173.98491(11)# 139(3) ms α (90%) 170Ir (3−)
β+ (10%) 174Pt
174mAu 130(50)# keV 162(2) ms α? 170Ir (9+)
β+? 174Pt
175Au 79 96 174.98132(4) 200(3) ms α (88%) 171Ir 1/2+
β+ (12%) 175Pt
175mAu 164(11)# keV 136(1) ms α (75%) 171Ir (11/2−)
β+ (25%) 175Pt
176Au 79 97 175.98012(4) 1.05(1) s α (75%) 172Ir (3−,4−)
β+ (25%) 176Pt
176mAu[n 9] 139(13) keV 1.36(2) s α? 172Ir (8+,9+)
β+? 176Pt
177Au 79 98 176.976870(11) 1.501(20) s β+ (60%) 177Pt 1/2+
α (40%) 173Ir
177mAu 190(7) keV 1.193(13) s α (60%) 173Ir 11/2−
β+ (40%) 177Pt
178Au 79 99 177.976057(11) 3.4(5) s β+ (84%) 178Pt (2+,3−)
α (16%) 174Ir
178m1Au 50.3(2) keV 300(10) ns IT 178Au (4−,5+)
178m2Au 186(14) keV 2.7(5) s β+ (82%) 178Pt (7+,8−)
α (18%) 174Ir
178m3Au 243(14) keV 390(10) ns IT 178Au (5+,6)
179Au 79 100 178.973174(13) 7.1(3) s β+ (78.0%) 179Pt 1/2+
α (22.0%) 175Ir
179mAu 89.5(3) keV 327(5) ns IT 179Au (3/2−)
180Au 79 101 179.9724898(51) 7.9(3) s β+ (99.42%) 180Pt (1+)
α (0.58%) 176Ir
181Au 79 102 180.970079(21) 13.7(14) s β+ (97.3%) 181Pt (5/2−)
α (2.7%) 177Ir
182Au 79 103 181.969614(20) 15.5(4) s β+ (99.87%) 182Pt (2+)
α (0.13%) 178Ir
183Au 79 104 182.967588(10) 42.8(10) s β+ (99.45%) 183Pt 5/2−
α (0.55%) 179Ir
183mAu 73.10(1) keV >1 μs IT 183Au (1/2)+
184Au 79 105 183.967452(24) 20.6(9) s β+ (99.99%) 184Pt 5+
α (0.013%) 180Ir
184mAu 68.46(4) keV 47.6(14) s β+ (70%) 184Pt 2+
IT (30%) 184Au
α (0.013%) 180Ir
185Au 79 106 184.9657989(28) 4.25(6) min β+ (99.74%) 185Pt 5/2−
α (0.26%) 181Ir
185mAu[n 9] 50(50)# keV 6.8(3) min β+ 185Pt 1/2+#
IT? 185Au
186Au 79 107 185.965953(23) 10.7(5) min β+ 186Pt 3−
α (8×10−4%) 182Ir
186mAu 227.77(7) keV 110(10) ns IT 186Au 2+
187Au 79 108 186.964542(24) 8.3(2) min β+ 187Pt 1/2+
α? 183Ir
187mAu 120.33(14) keV 2.3(1) s IT 187Au 9/2−
188Au 79 109 187.9652480(29) 8.84(6) min β+ 188Pt 1−
189Au 79 110 188.963948(22) 28.7(4) min β+ 189Pt 1/2+
α? (<3×10−5%) 185Ir
189m1Au 247.25(16) keV 4.59(11) min β+ 189Pt 11/2−
IT? 189Au
189m2Au 325.12(16) keV 190(15) ns IT 189Au 9/2−
189m3Au 2554.8(8) keV 242(10) ns IT 189Au 31/2+
190Au 79 111 189.964752(4) 42.8(10) min β+ 190Pt 1−
α? (<10−6%) 186Ir
190mAu[n 9] 200(150)# keV 125(20) ms IT 190Au 11−#
β+? 190Pt
191Au 79 112 190.963716(5) 3.18(8) h β+ 191Pt 3/2+
191m1Au 266.2(7) keV 920(110) ms IT 191Au 11/2−
191m2Au 2489.6(9) keV 402(20) ns IT 191Au 31/2+
192Au 79 113 191.964818(17) 4.94(9) h β+ 192Pt 1−
192m1Au 135.41(25) keV 29 ms IT 192Au 5+
192m2Au 431.6(5) keV 160(20) ms IT 192Au 11−
193Au 79 114 192.964138(9) 17.65(15) h β+ 193Pt 3/2+
193m1Au 290.20(4) keV 3.9(3) s IT (99.97%) 193Au 11/2−
β+ (0.03%) 193Pt
193m2Au 2486.7(6) keV 150(50) ns IT 193Au 31/2+
194Au 79 115 193.9654191(23) 38.02(10) h β+ 194Pt 1−
194m1Au 107.4(5) keV 600(8) ms IT 194Au 5+
194m2Au 475.8(6) keV 420(10) ms IT 194Au 11−
195Au 79 116 194.9650378(12) 186.01(6) d EC 195Pt 3/2+
195m1Au 318.58(4) keV 30.5(2) s IT 195Au 11/2−
195m2Au 2501(20)# keV 12.89(21) μs IT 195Au 31/2(−)
196Au 79 117 195.966571(3) 6.165(11) d β+ (93.0%) 196Pt 2−
β− (7.0%) 196Hg
196m1Au 84.656(20) keV 8.1(2) s IT 196Au 5+
196m2Au 595.66(4) keV 9.603(22) h IT 196Au 12−
197Au[n 10] 79 118 196.9665701(6) Observationally Stable[n 11] 3/2+ 1.0000
197m1Au 409.15(8) keV 7.73(6) s IT 197Au 11/2−
197m2Au 2532.5(10) keV 150(5) ns IT 197Au 27/2+#
198Au 79 119 197.9682437(6) 2.69464(14) d β− 198Hg 2−
198m1Au 312.2227(20) keV 124(4) ns IT 198Au 5+
198m2Au 811.9(15) keV 2.272(16) d IT 198Au 12−
199Au 79 120 198.9687666(6) 3.139(7) d β− 199Hg 3/2+
199mAu 548.9405(21) keV 440(30) μs IT 199Au 11/2−
200Au 79 121 199.970757(29) 48.4(3) min β− 200Hg (1−)
200mAu 1010(40) keV 18.7(5) h β− (84%) 200Hg 12−
IT (16%) 200Au
201Au 79 122 200.971658(3) 26.0(8) min β− 201Hg 3/2+
201m1Au 594(5) keV 730(630) μs IT 201Au 11/2-
201m2Au 1610(5) keV 5.6(24) μs IT 201Au 19/2+#
202Au 79 123 201.973856(25) 28.4(12) s β− 202Hg (1−)
203Au 79 124 202.9751545(33) 60(6) s β− 203Hg 3/2+
203mAu 641(3) keV 140(44) μs IT 203Au 11/2−#
204Au 79 125 203.97811(22)# 38.3(13) s β− 204Hg (2−)
204mAu 3816(500)# keV 2.1(3) μs IT 204Au 16+#
205Au 79 126 204.98006(22)# 32.0(14) s β− 205Hg 3/2+#
205m1Au 907(5) keV 6(2) s IT? 205Au 11/2−#
β−? 205Hg
205m2Au 2849.7(4) keV 163(5) ns IT 205Au 19/2+#
206Au 79 127 205.98477(32)# 47(11) s β− 206Hg 6+#
207Au 79 128 206.98858(32)# 3# s
[>300 ns] 		β−? 207Hg 3/2+#
β−, n? 206Hg
208Au 79 129 207.99366(32)# 20# s
[>300 ns] 		β−? 208Hg 6+#
β−, n? 207Hg
209Au 79 130 208.99761(43)# 1# s
[>300 ns] 		β−? 209Hg 3/2+#
β−, n? 208Hg
210Au 79 131 210.00288(43)# 10# s
[>300 ns] 		β−? 210Hg 6+#
β−, n? 209Hg
This table header & footer:
  1. ^ mAu – 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. ^ a b c # – Values marked # are not purely derived from experimental data, but at least partly from trends of neighboring nuclides (TNN).
  5. ^ Modes of decay:
    EC: Electron capture


    IT: Isomeric transition


    p: Proton emission
  6. ^ Bold italics symbol as daughter – Daughter product is nearly stable.
  7. ^ Bold symbol as daughter – Daughter product is stable.
  8. ^ ( ) spin value – Indicates spin with weak assignment arguments.
  9. ^ a b c d Order of ground state and isomer is uncertain.
  10. ^ Potential material for salted bombs
  11. ^ Theoretically predicted to undergo α decay to 193Ir

See also

[edit]

Daughter products other than gold

References

[edit]
Revisions and contributorsEdit on WikipediaRead on Wikipedia

Isotopes of gold

View on Grokipedia
from Grokipedia
Gold (^{79}Au) has one stable isotope, ^{197}Au, which makes up 100% of naturally occurring gold and has an atomic mass of 196.966569 u. There are 40 known radioactive isotopes of gold, ranging in mass number from ^{169}Au to ^{210}Au, with half-lives spanning from microseconds to over 180 days for the longest-lived, ^{195}Au. These isotopes exhibit various decay modes, including beta minus (β⁻), electron capture (EC), and alpha (α) decay, and are produced primarily through nuclear reactions in accelerators or reactors rather than occurring naturally. The lightest isotope, ^{169}Au, was discovered in 2025. Among the radioactive isotopes, ^{198}Au is particularly notable for its applications in , with a of 2.694 days and decay primarily via β⁻ emission to stable ^{198}Hg, accompanied by gamma rays suitable for and . It has been used in for treating cancers such as and cervical tumors, as well as in colloidal form for liver function diagnostics. Other isotopes like ^{199}Au ( 3.14 days) and ^{194}Au ( 1.58 days) have been studied for nuclear but see limited practical use. The nuclear properties of isotopes provide insights into heavy-element , including shape transitions from spherical to deformed structures in neutron-deficient isotopes around mass numbers 190–200, as revealed by laser spectroscopy and isotope shift measurements. All isotopes beyond ^{197}Au are synthetic, and their study contributes to understanding beta-delayed fission and astrophysical processes.

Fundamental Characteristics

Stable Isotope

Gold has a single stable isotope, ^{197}Au, which constitutes essentially 100% of naturally occurring . This isotope has an atomic mass of 196.966570(4) u. The nucleus of ^{197}Au contains 79 protons and 118 neutrons, making it the heaviest known stable nucleus with an odd number of protons and an even number of neutrons. As a , exhibits no significant isotopic variation in natural samples, with ^{197}Au's nuclear spin of 3/2^+ contributing to its exceptional longevity. The primordial abundance of ^{197}Au traces back to the rapid neutron-capture process (r-process) during the in core-collapse supernovae or, more prominently, mergers of stars, where intense fluxes build up heavy elements beyond iron. Since its formation in the early universe, ^{197}Au has shown no measurable decay over the age of the solar system or Earth's 4.5-billion-year history, underscoring its nuclear stability. This enduring presence explains 's role in primordial geochemical reservoirs, though its low crustal abundance (about 0.004 ppm) reflects dilution during planetary formation. Gold's persistence as native metal in Earth's crust stems from its chemical nobility, largely due to the electron configuration [Xe] 4f^{14} 5d^{10} 6s^1, where relativistic effects stabilize the 6s orbital and enhance inertness toward oxidation, corrosion, and most acids except aqua regia. This electronic structure results in a high ionization energy and low reactivity, allowing gold to remain uncombined in placer deposits and hydrothermal veins without forming stable compounds under surface conditions.

Range and Discovery of Isotopes

Gold has 42 known isotopes, spanning mass numbers from ^{169}Au to ^{210}Au, of which only ^{197}Au is and all others are radioactive. These isotopes exhibit a wide range of nuclear properties, with the neutron-deficient lighter isotopes often decaying via proton or alpha emission and the neutron-rich heavier ones primarily through . The isotopic chain reflects the challenges in synthesizing and observing extreme nuclides near the proton drip line and neutron excess limits, contributing to broader understanding of nuclear structure in the lead region. The discovery of gold isotopes began in the 1930s with the advent of techniques. The first radioisotopes included ^{198}Au, produced by on targets, and ^{199}Au, produced by neutron irradiation of targets followed by of ^{199}Pt, at facilities like the Berkeley , marking early successes in artificial synthesis. These initial findings laid the groundwork for exploring 's nuclear landscape, with subsequent decades seeing incremental additions through irradiations and early accelerator experiments. By the 2000s, comprehensive mapping of the gold isotopic range was achieved using advanced particle accelerators, including the ISOLDE facility at and the Holifield Radioactive Ion Beam Facility at (ORNL). These efforts enabled the production and identification of both light and heavy via multinucleon transfer reactions, fusion-evaporation, and processes. The heaviest known isotope, ^{210}Au, was first observed in 2010 through projectile fragmentation, while the lightest, ^{169}Au, was discovered in 2018 at 's MARA separator via heavy-ion fusion reactions on and targets, confirming from its . No radioisotopes of occur naturally in significant quantities, limited to potential trace primordial remnants that have long decayed, with ^{197}Au comprising the entirety of natural abundance. This exclusivity underscores the role of artificial production in studying 's nuclear properties.

Nuclear Properties

Decay Modes and Half-Lives

radioisotopes exhibit decay modes that depend primarily on their position relative to the stable isotope ^{197}Au, with neutron-rich isotopes (A > 197) favoring beta minus (β⁻) decay to corresponding mercury isotopes, while proton-rich isotopes (A < 197) predominantly undergo electron capture (EC) to platinum isotopes. For instance, the neutron-rich ^{198}Au decays via β⁻ to ^{198}Hg, with a decay equation given by 79198Au→80198Hg+e−+νˉe^{198}_{79}\mathrm{Au} \to ^{198}_{80}\mathrm{Hg} + e^{-} + \bar{\nu}_{e} and a Q-value of 1.371 MeV for the transition. This isotope decays by β⁻ emission with a branching ratio of essentially 100% (EC < 0.002%). In contrast, the proton-rich ^{195}Au undergoes EC decay to ^{195}Pt. Alpha decay is observed in some neutron-deficient (proton-rich) gold isotopes, such as lighter ones beyond the proton drip line, where ^{177}Au, for example, exhibits both α decay to ^{173}Ir and β⁺/EC branches. Half-lives of gold radioisotopes span a broad range, often categorized by duration to reflect their practical handling and applications: long-lived (>1 day), medium-lived (hours to days), and short-lived (<1 hour). Long-lived isotopes include ^{195}Au with a half-life of 186.1 days, primarily decaying via EC. Medium-lived examples encompass ^{198}Au at 2.697 days, dominated by β⁻ decay. Short-lived isotopes, such as ^{177}Au with a half-life of 1.5 seconds, typically involve rapid β⁺, EC, or α processes due to their proximity to instability limits. These categorizations highlight the diversity in nuclear stability across the gold isotopic , with longer half-lives generally associated with isotopes closer to the line of stability.

Nuclear Stability and Magic Numbers

Gold (Z = 79) lies in close proximity to the proton magic number 82, a shell closure that enhances nuclear stability through the filling of the 1h_{11/2} proton orbital in the nuclear shell model. This positioning near Z = 82 contributes to the relative stability of mid-mass gold isotopes, as the partial filling of subshells near closed shells reduces deformation and strengthens binding. For neutrons, the magic number N = 126, corresponding to the closure of the 1i_{13/2} orbital, plays a key role in the stability of heavier gold isotopes such as ^{205}Au. This neutron shell closure influences the nuclear structure in the region, leading to longer half-lives for isotopes like ^{195}Au (N = 116) and the stable ^{197}Au (N = 118) by stabilizing configurations against beta decay. Additionally, ^{197}Au exhibits enhanced stability due to a closed neutron subshell at N = 118, which resists beta decay by maintaining a favorable neutron-proton imbalance. Binding energy trends in gold isotopes can be understood through the semi-empirical mass formula (SEMF), which approximates the as B(A,Z)≈avA−asA2/3−acZ(Z−1)A1/3+aa(A−2Z)2A+δ,B(A, Z) \approx a_v A - a_s A^{2/3} - a_c \frac{Z(Z-1)}{A^{1/3}} + a_a \frac{(A - 2Z)^2}{A} + \delta, where ava_v, asa_s, aca_c, and aaa_a are the volume, surface, , and asymmetry coefficients, respectively, and δ\delta is the pairing term. For , with its odd proton number, the SEMF predicts an odd-A preference due to the positive pairing energy for odd-even (odd Z, even N) configurations, favoring greater stability for isotopes like ^{197}Au over even-A neighbors. This pairing effect, combined with proximity to shell closures, positions isotopes in a relatively region of the nuclear chart.

Isotopic Inventory

Long-Lived Radioisotopes

Long-lived radioisotopes of are those with half-lives greater than one day, making them suitable for applications requiring extended observation periods, such as certain or material studies. The most of these is ^{195}Au, which decays primarily by (EC) to ^{195}Pt, with no short-lived daughter products that could complicate measurements. This isotope's is particularly advantageous for long-term nuclear studies, as it avoids the production of transient radionuclides. ^{195}Au has a of 186.01 ± 0.06 days and a ground-state spin-parity of 3/2^+. The Q-value for its EC decay is 226.8 ± 1.2 keV. It is typically produced artificially via on ^{194}Pt or reactions in high-energy particle accelerators, such as proton irradiation of or targets. Another notable example is ^{196}Au, with a of 6.1669 ± 0.0006 days and spin-parity of 2^-. It decays by EC/β^+ (93%) to ^{196}Pt and β^- (7%) to ^{196}Hg, with a total of approximately 1.9 MeV. Production occurs through irradiation of platinum targets or (p,γ) reactions on ^{196}Pt. The following table summarizes key nuclear data for selected long-lived gold radioisotopes:
IsotopeHalf-LifeDecay ModeDaughter NuclideSpin-ParityQ-Value (keV)
^{195}Au186.01 dEC (100%)^{195}Pt3/2^+226.8 ± 1.2
^{196}Au6.1669 dEC/β^+ (93%), β^- (7%)^{196}Pt, ^{196}Hg2^-~1900
^{198}Au2.6941 dβ^- (100%)^{198}Hg2^-962 ± 5
^{199}Au3.139 dβ^- (100%)^{199}Hg3/2^+753 ± 5
These isotopes are produced primarily through artificial methods like reactor irradiation or reactions, with no significant primordial traces observed in natural due to their relatively short half-lives compared to Earth's age.

Short-Lived Radioisotopes

Short-lived radioisotopes of , defined here as those with half-lives under one day, are entirely synthetic and do not occur in . They are produced via high-energy nuclear reactions in particle accelerators, such as , fragmentation, or fusion-evaporation processes, and serve primarily as probes for studying nuclear structure, decay mechanisms, and reaction dynamics in neutron-deficient or neutron-rich regions. A representative example is ^{188}Au, which has a half-life of 8.84(6) minutes and decays predominantly by electron capture (with possible minor β⁺ contributions) to stable ^{188}Pt, emitting γ rays such as 87.3 keV. This isotope was first identified in 1955 through proton-induced reactions on gold targets followed by chemical separation at Berkeley. In the proton-rich sector, isotopes like ^{170}Au, observed in spallation reactions at facilities such as GSI Helmholtz Centre, have extremely brief half-lives of 310(50) μs and decay mainly by proton emission (∼85%) to ^{169}Pt with a minor α-decay branch (∼15%) to ^{166}Ir. Discovered in 2002 through the fusion-evaporation reaction ^{96}Ru(^{78}Kr, p3n) at Argonne National Laboratory, it provides data on proton drip-line behavior and shell effects. The ^{177m}Au, with a of 18.5 minutes, decays by isomeric transition and contributes to studies of shape coexistence in light gold isotopes, though detailed production typically involves heavy-ion reactions at accelerators. These fleeting nuclides, contrasting with longer-lived counterparts, enable time-resolved observations of nuclear reactions but limit practical applications beyond fundamental .

Production and Applications

Artificial Production Methods

Artificial production of gold isotopes primarily occurs through nuclear reactions in reactors, accelerators, and specialized facilities, targeting radioactive isotopes beyond the stable ^{197}Au. The most straightforward method involves on natural , where thermal neutrons are absorbed by ^{197}Au nuclei in nuclear reactors. This (n,γ) reaction produces the medically relevant ^{198}Au isotope, with the process described by : 197Au+n→198Au+γ^{197}\mathrm{Au} + n \rightarrow ^{198}\mathrm{Au} + \gamma The thermal neutron capture cross-section for this reaction is 98.65 ± 0.09 barns, enabling efficient production in high-flux environments. Charged particle reactions, typically performed at cyclotrons, allow for the synthesis of various isotopes by bombarding or mercury targets with protons or deuterons. For instance, proton irradiation of enriched ^{196}Pt via the (p,γ) reaction yields stable ^{197}Au, while deuteron-induced reactions on natural or enriched , such as natPt(d,x)^{198}Au, produce ^{198}Au with optimal yields at deuteron energies below 15 MeV. These reactions have measured cross-sections that align partially with evaluated nuclear libraries like TENDL-2013, facilitating no-carrier-added production when using enriched targets. For neutron-richer gold isotopes near A ≈ 200, heavy-ion fusion-evaporation reactions are employed at facilities like the Flerov Laboratory of Nuclear Reactions (FLNR) at JINR in . These involve accelerating medium-mass ions, such as carbon or beams, onto heavy targets like or , followed by from the compound nucleus to form isotopes such as ^{200}Au or heavier variants. Cross-sections for these processes are typically low, on the order of microbarns, reflecting the challenges in producing neutron-excess nuclei in this mass region.

Uses in Medicine and Research

(¹⁹⁸Au) has been used in for treating various cancers, including through seed implants, though it has largely been supplanted by other isotopes like ¹²⁵I in modern practice. It continues to be used in applications such as mold for oral cancers. This isotope's of approximately 2.7 days enables effective short-term while minimizing long-term exposure to surrounding healthy tissues, making it suitable for permanent seed implants involving 30–100 seeds per procedure. Historical applications date back to the 1950s, when ¹⁹⁸Au was among the first artificial isotopes used for interstitial in and other tumors. In addition to solid tumors, colloidal ¹⁹⁸Au has been employed in radiosynovectomy since the 1950s to manage , such as , by injecting radioactive particles intra-articularly to induce synovial and reduce joint inflammation. The first using colloidal ¹⁹⁸Au for persistent knee effusions in patients occurred in 1963, establishing its role in alleviating pain and swelling when other therapies fail. This treatment remains in use globally, particularly for larger joints like the , due to the colloid's ability to localize within the synovium. In nuclear research, ¹⁹⁸Au serves as a standard flux monitor for measuring thermal neutron densities owing to its high thermal neutron capture cross-section of 98.65 barns, which allows precise and subsequent gamma-ray detection for quantification. Gold foils enriched in ¹⁹⁷Au are commonly irradiated in reactors to determine in experiments, providing accurate in high-flux environments like fission reactors. For studying , employs the stable ¹⁹⁷Au to probe electronic structures and oxidation states, revealing insights into bonding and valence in aurous (Au(I)) and auric (Au(III)) species through isomer shifts correlated with s-electron density. This technique has been instrumental in characterizing pharmaceutical gold compounds, such as sodium aurothiomalate, and supported catalysts, where spectral parameters distinguish metallic gold from ionic forms. Emerging applications involve ¹⁹⁸Au incorporated into gold nanoparticles for targeted radiotherapy, enhancing tumor uptake and radiosensitization in and cancers through post-synthesis. These radiolabeled nanoparticles demonstrate antiproliferative effects and improved intratumoral delivery, with ongoing preclinical evaluations as of 2023 exploring their therapeutic potential. Recent 2025 studies have explored ¹⁹⁸Au nanoparticles conjugated with therapeutic antibodies like for enhanced targeted delivery in and cancers, demonstrating improved efficacy in preclinical models. Additionally, green synthesis approaches for ¹⁹⁸Au nanoparticles have shown antiproliferative effects in tumor cells.

References

  1. https://www.chemlin.org/chemical-elements/gold-isotopes.php
  2. https://www.chem.ualberta.ca/~massspec/atomic_mass_abund.pdf
  3. https://www.webelements.com/gold/isotopes.html
  4. https://www.thoughtco.com/gold-facts-606539
  5. https://www.nndc.bnl.gov/nsr/nsrlink.jsp?2023Cu04
  6. https://physics.nist.gov/cgi-bin/Compositions/stand_alone.pl?ele=Au
  7. https://www.chemlin.org/isotope/gold-197
  8. https://atom.kaeri.re.kr/cgi-bin/nuclide?nuc=Au197
  9. https://link.aps.org/doi/10.1103/RevModPhys.93.015002
  10. https://periodic-table.rsc.org/element/79/gold
  11. https://wou.edu/chemistry/courses/online-chemistry-textbooks/ch150-preparatory-chemistry/ch150-chapter-2-atoms-periodic-trends/
  12. https://chem.libretexts.org/Bookshelves/Inorganic_Chemistry/Supplemental_Modules_and_Websites_(Inorganic_Chemistry)/Descriptive_Chemistry/Elements_Organized_by_Block/d-Block_Elements/Group_11:_Transition_Metals/Chemistry_of_Gold
  13. https://indico.cern.ch/event/686407/contributions/2916817/contribution.pdf
  14. https://www.nndc.bnl.gov/nudat3/
  15. https://arxiv.org/pdf/0903.1797.pdf
  16. https://doi.org/10.1016/j.adt.2009.12.001
  17. https://www.chemlin.org/isotope/gold-210
  18. https://www-nds.iaea.org/livechart/
  19. http://www.lnhb.fr/nuclides/Au-198_com.pdf
  20. https://www.sciencedirect.com/science/article/pii/037594746890571X
  21. https://www.lnhb.fr/nuclides/Au-195_com.pdf
  22. https://periodictable.com/Isotopes/079.177/index.full.prod.html
  23. https://arxiv.org/pdf/0805.2561
  24. https://escholarship.org/content/qt0tv690r9/qt0tv690r9.pdf
  25. https://www.epj-conferences.org/articles/epjconf/pdf/2014/03/epjconf_inpc2013_01019.pdf
  26. https://personalpages.manchester.ac.uk/staff/Sean.Freeman/pc3121/semi-empirical.pdf
  27. https://www.nndc.bnl.gov/nudat2/getdataset.jsp?nucleus=195Au
  28. https://www.sciencedirect.com/science/article/pii/S0168583X98002225
  29. https://www.nndc.bnl.gov/nudat2/getdataset.jsp?nucleus=196Au
  30. https://www.nndc.bnl.gov/nudat2/getdataset.jsp?nucleus=198Au
  31. https://www.nndc.bnl.gov/nudat2/getdataset.jsp?nucleus=199Au
  32. https://www.sciencedirect.com/science/article/pii/S0092640X09000862
  33. https://atom.kaeri.re.kr/cgi-bin/decay?Au-188%20EC
  34. https://www-nds.iaea.org/amdc/nubase/b-mflza1.pdf
  35. https://www.sciencedirect.com/science/article/abs/pii/S0306454923004504
  36. https://pubs.aip.org/aip/acp/article/1711/1/080001/802131/Cyclotron-produced-198gAu-a-potential-radionuclide
  37. https://link.aps.org/doi/10.1103/PhysRevC.96.024602
  38. https://nrl.mit.edu/facilities/medical-isotope-irradiations/
  39. https://pmc.ncbi.nlm.nih.gov/articles/PMC7542347/
  40. https://www.sciencedirect.com/science/article/abs/pii/S1538472107002863
  41. https://www.iaea.org/sites/default/files/19/09/radiosynovectomy-agents.pdf
  42. https://journals.sagepub.com/doi/10.1177/1759720X211055309
  43. https://jnm.snmjournals.org/content/46/1_suppl/48S
  44. https://link.springer.com/article/10.1007/s13404-011-0039-0
  45. https://www.sciencedirect.com/science/article/abs/pii/S1350448703002889
  46. https://link.aps.org/doi/10.1103/PhysRevC.71.054322
  47. https://ui.adsabs.harvard.edu/abs/1970JChPh..53.4249F/abstract
  48. https://pubs.acs.org/doi/10.1021/ic50183a050
  49. https://www.researchgate.net/publication/222114682_Supported_gold_catalysts_studied_with_197Au_Mossbauer_effect_spectroscopy
  50. https://pubs.acs.org/doi/10.1021/acs.molpharmaceut.5c00288
  51. https://pubs.rsc.org/en/content/articlehtml/2025/tb/d5tb00815h
  52. https://pmc.ncbi.nlm.nih.gov/articles/PMC10747377/
  53. https://pubs.acs.org/doi/10.1021/acsomega.5c01385
  54. https://www.researchgate.net/publication/341747593_Radioactive_Gold_Nanoparticle_in_Two_Forms_79198Au_GNPs_and_99mTc-GNPs_for_Lung_Cancer_Antiproliferative_Induction_and_Intralesional_Imaging_A_Proof_of_Concept
Add your contribution
Related Hubs
User Avatar
No comments yet.