Abstract: This invention relates to novel nucleotide-based compounds, methods of making radiolabeled compounds and use of such compounds for diagnostic imaging. Provided are compounds according to Formula (I) A-B-L-C, wherein A stands for an aptamer, B is absent or stands for a bridging structure, L is a linker, and C is a metal ion chelator. All substituents are defined in detail in the description. Preferred embodiments of said compounds bind to Tenascin-C.

Abstract: The object of the present invention is solved by compositions of peptide linkers and their use for synthesis and annealing of aptamer oligonucleotides in form of dimers. The present invention in particularly provides said compositions for the use as a diagnostic and/or therapeutic agent. In another preferred embodiment the present invention relates to a kit for preparing a radiopharmaceutical preparation, said kit comprising a vial comprising a quantity of the compound according to the invention. A further preferred embodiment of the present invention relates to methods of producing said compounds, comprising synthesis of said compound in an automated peptide synthesizer. In another preferred embodiment the present invention concerns the use of said compounds according to the present invention for the manufacture of a medicament, preferably for diagnosis or therapy of proliferative diseases.