title: Fast indirect fluorine-18 labeling of protein/peptide using the useful 6-fluoronicotinic acid-2,3,5,6-tetrafluorophenyl prosthetic group: A method comparable to direct fluorination.
abstract: Fluorine-18 labeling of biomolecules is mostly performed by an indirect labeling method using a prosthetic group. Fluorine-18 labeled 6-fluoronicotinic acid-2,3,5,6-tetrafluorophenyl ester is a useful prosthetic group to radiolabel a protein. Recently, we reported an improved preparation of this prosthetic group. To test the conjugation efficiency of the labeled ester prepared by this method, we have performed conjugation reactions with a peptide, a protein, and a small molecule. Prostate-specific membrane antigen targeting small molecule [18F]DCFPyL, αvβ3 integrin receptors targeting peptide [18F]c(RGDfK) and [18F]albumin were prepared in good radiochemical yields. The conjugation reactions were completed at 40°C to 50°C in 10 minutes. The overall radiochemical yield was 25% to 43% in 30 to 45 minutes.
authors.affiliation: Imaging Probe Development Center, National Heart, Lung, and Blood Institute, National Institutes of Health, Rockville, MD, USA.
authors.forename: Falguni
authors.initials: F
authors.lastname: Basuli
authors.affiliation: Imaging Probe Development Center, National Heart, Lung, and Blood Institute, National Institutes of Health, Rockville, MD, USA.
authors.forename: Xiang
authors.initials: X
authors.lastname: Zhang
authors.affiliation: Imaging Probe Development Center, National Heart, Lung, and Blood Institute, National Institutes of Health, Rockville, MD, USA.
authors.forename: Carolyn C
authors.initials: CC
authors.lastname: Woodroofe
authors.affiliation: Molecular Imaging Program, National Cancer Institute, National Institutes of Health, Bethesda, MD, USA.
authors.forename: Elaine M
authors.initials: EM
authors.lastname: Jagoda
authors.affiliation: Molecular Imaging Program, National Cancer Institute, National Institutes of Health, Bethesda, MD, USA.
authors.forename: Peter L
authors.initials: PL
authors.lastname: Choyke
authors.affiliation: Imaging Probe Development Center, National Heart, Lung, and Blood Institute, National Institutes of Health, Rockville, MD, USA.
authors.forename: Rolf E
authors.initials: RE
authors.lastname: Swenson
mesh_terms: D000418:Albumins / Q000737:chemistry*; D000595:Amino Acid Sequence; D000954:Antigens, Surface / Q000737:chemistry*; D005462:Fluorine Radioisotopes / Q000737:chemistry*; D043425:Glutamate Carboxypeptidase II / Q000737:chemistry*; D054879:Halogenation; D007553:Isotope Labeling / Q000379:methods*; D007700:Kinetics; D009842:Oligopeptides / Q000737:chemistry*
chemical_list: D000418:Albumins; D000954:Antigens, Surface; D005462:Fluorine Radioisotopes; D009842:Oligopeptides; C047981:arginyl-glycyl-aspartic acid; C473848:FOLH1 protein, human; D043425:Glutamate Carboxypeptidase II; C000615276:Fluorine-18
keywords: F-18; peptide; protein; radiolabeling