Dendritic poly-chelator frameworks for multimeric bioconjugation

Starting from multifunctional triazacyclononane-triphosphinate chelator cores, dendritic molecules with the ability to bind metal ions within their framework were synthesized. A cooperative interaction of the chelator cages resulted in a markedly increased affinity towards ^67/68Ga^III. A hexameric PSMA inhibitor conjugate with high affinity (IC₅₀ = 1.2 nM) and favorable in vivo PET imaging properties demonstrated practical applicability. The novel scaffolds are useful for synthesis of structurally well-defined multimodal imaging probes or theranostics.