6533b854fe1ef96bd12ae7d7

RESEARCH PRODUCT

A no-carrier-added 72Se/72As isotope generator

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Siinznrary A no-carrier-added 72Se/72As generator has been developed for the isolation of 72As, relevant for eventual application in the syntheses of 72As-labelled radiophamaceuticals. Avoiding the addition of Se carrier and using a thennochromatographic destillation process, no-carrier-added 72As is nearly quantitatively released within 10 min. 72Se remains almost quantitatively (> 99.7%) in solution when a temperature of the separation process of 100°C is applied. Introdiiction Arsenic-72 is a positron emitting isotope with properties which are promising for eventual application in 72As-labelled radiopharmaceuticals. It has n positron emission rate of 88% and positron energies of EP+,,,,~ = 2.5 MeV; EP+,,,~~" = 1.0 MeV [l]. Although the positron emission decay is accompanied by photons of 834 keV (79.5%), 630 keV (7.9%), 1464.1 keV (1.1 %), and others (c 0.5%), the long physical half-life of 26 hours might turn 72As into the PET isotope of choice for biochemical / physiological processes with longer biological halflives. It can be directly produced at medium-energy cyclotrons via the