Introduction: The use of germanium-68 (68Ge)/gallium-68 (68Ga) generators is still limited when compared with the 99Mo/99mTc counterpart, mainly because of the absence of commercial kits and a kit-based method for preparing 68Ga-labelled radiopharmaceuticals in a reliable way. The present study aimed to develop and optimize a reliable direct labelling of DOTATOC with 68Ga through a kit-based approach. Materials and methods: A fraction of the eluate of two different 68Ge/68Ga generators was directly injected into a vial prefilled with precursor, buffer and scavenger (the prototype of a potential lyophilized kit). The vial was directly warmed to 100°C and then buffered with a 1.5 mol/l sodium ascorbate solution. The parameters influencing the reaction were studied and optimized. The efficacy of the method in terms of incorporation yield and quality of the final radiotracer was compared with preparations performed with two commercial automatic synthesizers by applying the tests prescribed in the European Pharmacopeia monograph for 68Ga-DOTATOC. Results: Under optimal conditions, the overall radiochemical yields of the kit-based process were 73 ± 4 and 69 ± 3% not decay-corrected for the IGG100 and itG generator, respectively. The radiochemical purity was 95 ±3% and the preparations were compliant with all specifications given in the pharmacopoeia monograph. Conclusion: The feasibility of a kit-based approach for the preparation of 68Ga-DOTATOC was proved and a first homemade version of a putative lyophilized kit was proposed.
- Kit-based synthesis
- Somatostatin analogues
ASJC Scopus subject areas
- Radiology Nuclear Medicine and imaging