Comparison of three different methods in [⁶⁸Ga]Ga‐PSMA11 radiolabeling

Abstract

In this study, quality control parameters such as radiochemical yield, radiochemical purity, and in vitro stability of gallium (68Ga)‐prostate‐specific membrane antigen‐11 ([68Ga]Ga‐PSMA11) radiopharmaceutical obtained in a research laboratory with three different synthesis algorithms were evaluated and compared. Gallium (68Ga) chloride precursor to be used in labeling in all three methods was obtained by using ITG brand 68Ge/68Ga generator. The first method for the [68Ga]Ga‐PSMA11 radiopharmaceutical was performed with the automated synthesis module, which is widely used in clinical practice. Its radiochemical yield, quality assurance, and stability met expectations. Radiolabeling success, suitability of quality control parameters, and in vitro stability of [68Ga]Ga‐PSMA11 radiopharmaceutical performed with ANMI kit were examined. The final product showed success in 68Ga‐complexation kinetics. All quality control criteria performed met the expectation for clinical applications. Direct cold labeling of PSMA11 ligand with sodium bicarbonate buffer was examined. Results were similar to the ANMI kit. Considering that all three methods are successful in radiochemical labeling, labeling with NaHCO3 buffer shows the labeling preference when we choose the cheap, practical, and easy labeling option.

Evaluation of quality control and initial imaging properties of labeled [68Ga]GaPSMA-11 by elution of Monrol [68Ge]/[68Ga] generator

“…Before being injected into the patient, quality control analyzes of the radiotracers were performed with radio-HPLC. The radiochemical purity of the obtained PET radiotracer was analyzed by the method described in our previous study [11].…”