Production and Purification of ⁷⁷Br Suitable for Labeling Monoclonal Antibodies Used in Tumor Imaging

Abstract

The irradiation of 400 mg As 2 0 3 with 30 MeV α-particles yields nearly pure "Br resulting from the 75 As (a,2n) 77 Br reaction.y-ray spectroscopy of the irradiated material at EOB + 20 h showed that the radionuclidic purity was >99%. The purification of 77Br from the As 2 0 3 target material is discussed. The irradiated powder is dissolved in boiling water. Anion-exchange column chromatography using Dowex AG 1X8 is performed. The 77 Br is eluted with 1 M NaHSO". The latter is removed by precipitation with methanol. After drying and redissolving the residue in 100 μΐ of water, a 77 Br solution with pH 6-8 is obtained suitable for the labeling of monoclonal antibodies. Recovery experiments with [ 76 As]As 2 0 3 have shown that after anionexchange chromatography less than 10" 5 % of the amount of arsenic is present in the NaHS0 4 aliquot of interest. The chemical state of the radiobromine is checked by 2 methods: HPLC anionchromatography and TLC. Both techniques proved the 77 Br to exist only in the bromide form.

A critical survey of experimental cross section data, comparison with nuclear model calculations and estimation of production yields of 77Br and 77Kr in no-carrier-added form via various nuclear processes

“…The neutron deficient radioisotopes of bromine have found some use in nuclear medicine, mainly due to a chemical behavior which is conducive to the synthesis of radiopharmacuticals [1][2][3][4][5][6]. Of all bromine radioisotopes the properties of 77 Br (T 1/2 = 56 h) are very suitable for in vivo studies.…”

Investigation of selenium compounds as targets for 76,77Br production using protons of energies up to 34 MeV

“…The radionuclides of bromine, such as 75 Br (T 1/2 = 1.6 h), 76 Br (T 1/2 = 16.0 h), 77 Br (T 1/2 = 57 h) and 80m Br (T 1/2 = 4.4 h), have excellent physical and chemical characteristics to be used either in imaging via Positron emission tomography (PET) or single photon emission tomography (SPECT), or for internal radiotherapy [1][2][3][4][5][6][7][8]. Charged particle accelerators are the most suitable tools for their production through different nuclear reactions using a wide variety of projectiles and targets .…”