Methods and compositions for improved f-18 labeling of proteins, peptides and other molecules

Abstract

The present application discloses compositions and methods of synthesis and use ofF- orF-labeled molecules of use in PET, SPECT and/or MR imaging. Preferably, theF orF is conjugated to a targeting molecule by formation of a complex with a group IIIA metal and binding of the complex to a bifunctional chelating agent, which may then be directly or indirectly attached to the targeting molecule. In other embodiments, theF orF labeled moiety may comprise a targetable construct used in combination with a bispecific antibody to target a disease-associated antigen. The disclosed methods and compositions allow the simple and reproducible labeling of molecules at very high efficiency and specific activity in 30 minutes or less. In preferred embodiments, the bifunctional chelating agent bound toF- orF-metal complex may be conjugated to the molecule to be labeled at a reduced temperature, e.g. room temperature.