68Ga-labelled DOTA-derivatised peptide ligands

Area of Science:

• Nuclear Medicine
• Radiopharmaceutical Chemistry

Background:

• Germanium-68/Gallium-68 (68Ge/68Ga) generators offer a practical, cyclotron-independent source for positron emission tomography (PET) radiopharmaceuticals.
• Efficient and safe handling of 68Ga eluates is crucial for labeling DOTA-derivatized peptide ligands for diagnostic imaging.

Purpose of the Study:

• To describe and validate a novel system for the safe and efficient processing of 68Ge/68Ga generator eluates.
• To assess the system's performance in labeling various DOTA-derivatized peptide ligands for PET applications.
• To confirm the system's suitability for routine clinical use by inexperienced personnel.

Main Methods:

• Development of a comprehensive system for concentration, purification, labeling, and purification of 68Ga eluates.
• Testing the system with DOTA-derivatized somatostatin derivatives and a DOTA-derivatized bombesin derivative.
• Evaluation of labeling yields and safety features in a "hot lab" setting.

Main Results:

• The system demonstrated efficient concentration and purification of 68Ga eluates.
• Successful labeling of DOTA-derivatized peptides (somatostatin and bombesin derivatives) was achieved with 10-20 nmol peptide amounts.
• Labeling yields of 50% were obtained for all tested peptides.
• Built-in safety precautions were validated for routine clinical application.

Conclusions:

• The described system provides a safe, efficient, and user-friendly method for preparing 68Ga-labeled peptides for PET imaging.
• The system's effectiveness and safety allow for its implementation in routine clinical settings, even by personnel without prior PET radiopharmaceutical preparation experience.
• This approach broadens access to cyclotron-independent PET radiopharmaceuticals.