Radiolabeling of multimeric neurotensin(8-13) analogs with the short-lived positron emitter fluorine-18.
Three methods for (18)F-labeling of dimeric and tetrameric neurotensin(8-13) derivatives were evaluated with respect to the labeling yield and the required peptide amounts. Labeling using N-succinimidyl-4-[(18)F]fluorobenzoate ([(18)F]SFB) gave low radiochemical yield for the dimeric peptides. Coupling of the tetramer with [(18)F]SFB was not successful. High yields were obtained for labeling of the aminooxy-functionalized neurotensin(8-13) dimer using 4-[(18)F]fluorobenzaldehyde ([(18)F]FBA) whilst coupling of the corresponding tetramer gave only low yields. Labeling of sulfydryl-functionalized neurotensin(8-13) derivatives using the maleinimide 4-[(18)F]fluorobenzaldehyde-O-[6-(2,5-dioxo-2,5-dihydro-pyrrol-1-yl)-hexyl]-oxime ([(18)F]FBAM) resulted in high radiochemical yields for both, the dimer and the tetramer. Therefore, [(18)F]FBAM seems to be the most suitable (18)F-labeling agent for multivalent neurotensin(8-13) derivatives.
Hultsch
Christina
C
Institute of Radiopharmacy, Research Center Rossendorf, P.O. Box 51 01 19, D-01314 Dresden, Germany.
Berndt
Mathias
M
Bergmann
Ralf
R
Wuest
Frank
F
D001547:Benzaldehydes / Q000737:chemistry; D001565:Benzoates / Q000737:chemistry; D019281:Dimerization; D004583:Electrons; D005462:Fluorine Radioisotopes / Q000737:chemistry*; D007553:Isotope Labeling; D008301:Maleimides / Q000737:chemistry; D009496:Neurotensin / Q000737:chemistry*; D010446:Peptide Fragments / Q000737:chemistry*; D013388:Succinimides / Q000737:chemistry
D001547:Benzaldehydes; D001565:Benzoates; D005462:Fluorine Radioisotopes; D008301:Maleimides; C518594:N-(6-(4-fluorobenzylidene)aminooxyhexyl)maleimide; D010446:Peptide Fragments; D013388:Succinimides; C075713:N-succinimidyl-4-fluorobenzoate; D009496:Neurotensin; C054381:neurotensin (8-13); C516422:4-fluorobenzaldehyde