Biological evaluation of 153Sm and 166Ho complexes with macrocyclic ligands containingacetate pendant arms as potential agents for therapy

摘要

153Sm and 166Ho complexes with the macrocyclic ligands TRITA (1,4,7,10-tetraazacyclotridecane-1,4,7,10-tetraacetic acid) and TETA (1,4,8,11-tetraazacyclotetradecane-1,4,8,11-tetraacetic acid) were synthesized in order to evaluate their in vitro and in vivo behaviour. Forcomparison, 153Sm/166Ho-DOTA complexes were also prepared. All complexes were synthesized inhigh radiochemical yield (> 98%) and high radiochemical purity presenting good in vitro stability inhuman serum. Biodistribution studies in mice showed that 153Sm/166Ho-TRITA have rapid tissueclearance, comparably to the corresponding DOTA complexes. In contrast with this and with thebiodistribution profile of 166Ho-TETA, 153Sm-TETA has a significant lower total excretion and asignificant liver and muscle uptake. In vitro and in vivo stability and the biological profile of theradiolanthanide complexes under study support the interest of 153Sm/166Ho-TRITA to be potentiallyused for targeted radiotherapy when conjugated to a biomolecule.