Universal Molecular Scaffold for Facile Construction of Multivalent and Multimodal Imaging Probes.

Multivalent and multimodal imaging probes are rapidly emerging as powerful chemical tools for visualizing various biochemical processes. Herein, we described a bifunctional chelator (BFC)-based scaffold that can be used to construct such promising probes concisely. Compared to other reported similar scaffolds, this new BFC scaffold demonstrated two major advantages: (1) significantly simplified synthesis due to the use of this new BFC that can serve as chelator and linker simultaneously; (2) highly efficient synthesis rendered by using either click chemistry and/or total solid-phase synthesis. In addition, the versatile utility of this molecular scaffold has been demonstrated by constructing several multivalent/multimodal imaging probes labeled with various radioisotopes, and the resulting radiotracers demonstrated substantially improved in vivo performance compared to the two individual monomeric counterparts.