Uranium-230

Properties and data of the isotope ²³⁰U.

Contents

General Data

Radioactive Decay

Parent Nuclides

Formation

Use in Medicine

Isotones und Isobares

Literature

Uranium-230 is a radioisotope of the chemical element uranium, which has 138 neutrons in its atomic nucleus in addition to the element-specific 92 protons; the sum of the number of these atomic nucleus building blocks results in a mass number of 230. The very short-lived, only artificially produced, unstable and therefore radioactive nuclide has no practical technical significance.

From a medical point of view, however, the radionuclide is a potential candidate for so-called targeted alpha therapy. The possibilities for producing and purifying isotopically pure uranium-230 are currently being investigated in more detail [1,2,3].

See also: List of individual Uranium isotopes (and general data sources).

General data

Name of the isotope:Uranium-230; U-230Symbol:²³⁰U or 23092UMass number A:230 (= number of nucleons)Atomic number Z:92 (= number of protons)Neutrons N:138Nucleon pairing (Z - N):even - evenNuclear ratio (N/Z ratio):1.5 (= neutron-proton ratio)Neutron excess (N-Z):46Isotopic mass:230.033940(5) u (atomic weight of Uranium-230)Nuclide mass:229.9834773 u (calculated nuclear mass without electrons)Mass excess:31.61491 MeVMass defect:1.881721352 u (per nucleus)Nuclear binding energy:1752.81214906 MeV (per nucleus)
7.62092239 MeV (average binding energy per nucleon)Separation energy:S_N = 7.667(7) MeV (first neutron)
S_P = 5.571(5) MeV (first proton)Half-life:20.23(2) dDecay constant λ:3.965663278317 × 10^-7 s^-1Specific activity α:1.038338385439 × 10⁺¹⁵ Bq g^-1
28063.19960647 Ci g^-1Spin and parity:
(nuclear angular momentum)0+Year of discovery:1948

Radioactive Decay

Half-life T_½ = 20.23(2) d respectively 1.747872 × 10⁶ seconds s.

Decay mode	Daughter	Probability	Decay energy	Details	γ energy (intensity)
α	²²⁶Th	100 %	5.9925(5) MeV	α: 5.8884(7) MeV [67.4(4) %] α: 5.8175(7) MeV [32.0(2) %]
CD	²²Ne	rare

Formation and radioactive decay of uranium-230

Parent Nuclides

Direct parent isotopes are: ²³⁴Pu, ²³⁰Pa, ²³⁰Np.

Formation

The artificial production of uranium-230 is based on the naturally occurring and readily available thorium-232; corresponding nuclear reactions include:

²³²Th(p,3n)²³⁰Pa,

²³²Th(d,4n)²³⁰Pa.

This initially produces protactinium-230, which decays to U-230 with a half-life of 17.4 days, emitting β-radiation.

Uranium-230 as a Radionuclide in Medicine

Uranium-230 is a radionuclide that emits α particles (helium-4 nuclei) and can potentially be used for targeted alpha therapy (TAT) of cancer. The nuclide first decays to Thorium-226; the α-radiation is increased by the radioactive decay products, which also emit alpha radiation (see decay scheme above). The five (relevant) subsequent alpha decays from each ²³⁰U decay event lead to an α-dose in the range of 28–34 MeV, which can be used in therapeutic applications [2]. The α-particles typically penetrate the organism to a depth of about 100 μm (some cell diameters) and cause local DNA damage and thus cell death, e.g. of cancer cells.

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 138) and isobaric (same nucleon number A = 230) with Uranium-230. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

Z	Isotone N = 138	Isobar A = 230
82	²²⁰Pb
83	²²¹Bi
84	²²²Po
85	²²³At
86	²²⁴Rn	²³⁰Rn
87	²²⁵Fr	²³⁰Fr
88	²²⁶Ra	²³⁰Ra
89	²²⁷Ac	²³⁰Ac
90	²²⁸Th	²³⁰Th
91	²²⁹Pa	²³⁰Pa
92	²³⁰U	²³⁰U
93	²³¹Np	²³⁰Np
94	²³²Pu	²³⁰Pu
95	²³³Am	²³⁰Am
96	²³⁴Cm
97	²³⁵Bk

External data and identifiers

CAS:15743-51-8InChI Key:JFALSRSLKYAFGM-QQVBLGSISA-NSMILES:[230U]PubChem:ID 167355Adopted Levels, Gammas:NuDat 230U

Literature and References

[1] - Aurelian Luca, Mihail-Răzvan Ioan:
²³⁰U nuclear decay data evaluation.
In: Applied Radiation and Isotopes, 134, (2018), DOI 10.1016/j.apradiso.2017.10.034.

[2] - Mitchell T. Friend, Tara Mastren, T. Gannon Parker et al.:
Production of ²³⁰Pa by proton irradiation of ²³²Th at the LANL isotope production facility: Precursor of ²³⁰U for targeted alpha therapy.
In: Applied Radiation and Isotopes, 156, 108973, (2020), DOI 10.1016/j.apradiso.2019.108973.

[3] - Miting Du, Thomas Dyer, Punam Thakur:
Simultaneous Separation of Protactinium-230 and Uranium-230 Isotopes from a Proton-Irradiated Thorium Matrix.
In: Analytical Chemistry, 96,15, (2024), DOI 10.1021/acs.analchem.3c05943.