Practıcal Aspects of 68Ga-Labelled Dota-Peptides for Peptide-Receptor Radionuclide Therapy

Abstract

68Gallium-labeled receptor ligands, such as 68Gallium DOTATOC, 68Gallium-DOTANOC, and 68Gallium-DOTATATE which are used in PET are becoming gold standard of 68Ga-labeled peptides. The 68Ga-labeled peptides show a rapid renal clearance and are rapidly accumulated in the tumors (80% within 30 minutes); concentration in tissues without expression of somatostatin receptors is low, providing higher contrast imaging. Here, this paper presents the practical aspects and the results of preparation and radiolabelling DOTA-peptides with TiO2-based commercially available 68Ge/68Ga generator by using fully automated radiopharmaceutical synthesis device. The radiochemical purity (RCP) of 68Ga-labeled DOTA-peptides has been investigated using high performance liquid chromatography (HPLC) and instant thin layer chromatography (ITLC). The labeling procedure resulted in high radiochemical yield. The system allows the fully automated, efficient and rapid preparation of 68Ga-DOTA-derivatized peptides.

Keywords

• 68Ga,DOTANOC,DOTATATE,peptides,PET

References

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