Preparation and biodistribution assessment of 68Ga-DKFZ-PSMA-617 for PET prostate cancer imaging

摘要

Prostate-specific membrane antigen(PSMA) is a useful target for diagnostic and therapeutic applications,and it is demonstrated that ^(68) Ga in conjugation with DKFZPSMA-617 is better than ^(68)Ga-PSMA-1 in biodistribution data after 1 h,but more preclinical data are still required.In this paper,we presented the additional preclinical data for ^(68)Ga-DKFZ-PSMA-617 and relevant aspects of its production.^(68) Ga was obtained from the SnO_2-based ^(68)Ge/ ^(68) Ga generator.Optimum conditions(p H,temperature,time and ligand concentration) for ^(68)Ga-DKFZPSMA-617 preparation were studied.Radiochemical purity of the radiolabeled compound was determined by HPLC and RTLC.After stability assessments,the complex was intravenously injected into rats.HPLC and ITLC characterizations indicated that the radiopharmaceutical could be prepared with radiochemical purity of [96 % and specific activity of 308.3 TBq/mmol at the optimized conditions(p H of 3.5–4,ligand amount of 2.4 nmol,temperature of90–95 C and reaction time of 10 min).Also,the biodistribution data showed no undesirable uptake in nontarget organs at any interval after injection.In fact,the activity is cleaned from blood and excreted rapidly via the kidneys.Generally,this compound can be considered as a wellestablished PET imaging agent.