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Site-Specific Radiofluorination of Biomolecules with 8-[(18)F]-Fluorooctanoic Acid Catalyzed by Lipoic Acid Ligase.

ABSTRACT: New methodologies for site-specifically radiolabeling proteins with (18)F are required to generate high quality radiotracers for preclinical and clinical applications with positron emission tomography. Herein, we report an approach by which we use lipoic acid ligase (LplA) to conjugate [(18)F]-fluorooctanoic acid to an antibody fragment bearing the peptide substrate of LplA. The mild conditions of the reaction preserve antibody immunoreactivity, and the efficiency of LplA allows for >90% yield even with very small amounts of peptidic precursor (1-10 nmol). These features are advantageous compared to the current gold standard in the field. Moreover, the methodology introduces a new application for an important tool in chemical biology.

SUBMITTER: Drake CR

PROVIDER: S-EPMC5712215 | biostudies-literature | 2016 Jun

REPOSITORIES: biostudies-literature

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Site-Specific Radiofluorination of Biomolecules with 8-[(18)F]-Fluorooctanoic Acid Catalyzed by Lipoic Acid Ligase.

Drake Christopher R CR Sevillano Natalia N Truillet Charles C Craik Charles S CS VanBrocklin Henry F HF Evans Michael J MJ

ACS chemical biology 20160331 6

New methodologies for site-specifically radiolabeling proteins with (18)F are required to generate high quality radiotracers for preclinical and clinical applications with positron emission tomography. Herein, we report an approach by which we use lipoic acid ligase (LplA) to conjugate [(18)F]-fluorooctanoic acid to an antibody fragment bearing the peptide substrate of LplA. The mild conditions of the reaction preserve antibody immunoreactivity, and the efficiency of LplA allows for >90% yield e ...[more]

PMID: 27008570

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