Measurement of evaporation-residue cross sections with light beams and deformed lanthanide target nuclei

To obtain a better understanding of the fusion reaction, we have focused on reactions involving deformed nuclei. Evaporation residue cross sections of the 169Tm+20Ne reaction were measured, from which we extracted the fusion excitation function. This is compared with literature data of the 169Tm+16O and 165Ho+20Ne systems. Irradiation with 20Ne ion beam has been carried out at the incident energy near the Coulomb barrier, where the effect of nuclear deformation is prominent. The results are consistent with the idea that the degree of deformation has an effect on the threshold value of the excitation functions near the Coulomb barrier

²¹¹ At-labeled immunoconjugate via a one-pot three-component double click strategy: practical access to α-emission cancer radiotherapeutics

© The Royal Society of Chemistry. α-Emission radiotherapeutics has potential to be one of most effective cancer therapeutics. Herein, we report a facile synthesis of an 211 At-labeled immunoconjugate for use as an α-emission molecular targeting therapy. We synthesized a tetrazine probe modified with closo-decaborate(2-), a prosthetic group that forms a bioavailable stable complex with 211 At. Our one-pot three-component double-click labeling method was used to attach decaborate to trastuzumab (anti-HER2 antibody) using decaborate-tetrazine and TCO-aldehyde probes without reducing the antibody binding affinity. Labeling the decaborate-attached trastuzumab with 211 At produced in the cyclotron at the RIKEN Nishina Center, at which highly radioactive 211 At can be produced, readily furnished the 211 At-labeled trastuzumab with a maximum specific activity of 15 MBq μg −1 and retention of the native binding affinity. Intratumor injection of the 211 At-labeled trastuzumab in BALB/c nude mice implanted with HER2-expressing epidermoid cancer cells yielded efficient accumulation at the targeted tumor site as well as effective suppression of tumor growth

²¹¹ At-labeled immunoconjugate via a one-pot three-component double click strategy: practical access to α-emission cancer radiotherapeutics

© The Royal Society of Chemistry. α-Emission radiotherapeutics has potential to be one of most effective cancer therapeutics. Herein, we report a facile synthesis of an 211 At-labeled immunoconjugate for use as an α-emission molecular targeting therapy. We synthesized a tetrazine probe modified with closo-decaborate(2-), a prosthetic group that forms a bioavailable stable complex with 211 At. Our one-pot three-component double-click labeling method was used to attach decaborate to trastuzumab (anti-HER2 antibody) using decaborate-tetrazine and TCO-aldehyde probes without reducing the antibody binding affinity. Labeling the decaborate-attached trastuzumab with 211 At produced in the cyclotron at the RIKEN Nishina Center, at which highly radioactive 211 At can be produced, readily furnished the 211 At-labeled trastuzumab with a maximum specific activity of 15 MBq μg −1 and retention of the native binding affinity. Intratumor injection of the 211 At-labeled trastuzumab in BALB/c nude mice implanted with HER2-expressing epidermoid cancer cells yielded efficient accumulation at the targeted tumor site as well as effective suppression of tumor growth

Production of Bh 266 in the Cm 248 (Na 23,5n) Bh 266 reaction and its decay properties

The nuclide 266Bh was produced in the 248Cm(23Na,5n)266Bh reaction at beam energies of 125.9, 130.6, and 135.3 MeV. Decay properties of 266Bh were investigated with a rotating wheel apparatus for α and spontaneous fission (SF) spectrometry under low background conditions attained by a gas-jet transport system coupled to the RIKEN gas-filled recoil ion separator. Based on genetically correlated α−α and α-SF decay chains, a total of 23 chains were assigned to 266Bh and its daughter nuclide 262Db and granddaughter 258Lr. The half-life of 266Bh was measured to be T1/2=10.0+2.6−1.7s which is an order of magnitude longer than the literature data. The α-particle energies of 266Bh disperse widely in the range of Eα=8.62–9.40MeV. The maximum production cross section for the 248Cm(23Na,5n)266Bh reaction was determined to be σ=57±14 pb at 130.6 MeV, whereas the upper limit for the 248Cm(23Na,4n)267Bh reaction was σ≤14 pb at 121.2 MeV. These cross sections are discussed by comparing with the literature data as well as the theoretical calculations