ABSTRACT
Objective:To produce 68Ga and automatically synthesize 68Ga-labeled drugs based on low-energy medical cyclotron solid target system. Methods:68Zn was electroplated on the surface of the target by electrodeposition. According to the principle of 68Zn(p, n) 68Ga nuclear reaction, 68Zn was irradiated by the 10 MeV medical cyclotron solid target system (30 μA, 30 min) to produce 68Ga, and the activity, nuclear purity, half-life and content of metal impurities of purified product were determined. 68Ga-prostate specific membrane antigen (PSMA)-11 and 68Ga-1, 4, 7, 10-tetraazacyclododecane-1, 4, 7, 10-tetraacetic acid- D-Phe1-Tyr3-Thr8-octreotide (DOTATATE) were synthesized automatically using 68Ga respectively, and the quality control analyses of drug properties, concentration, pH, radiochemical purity, sterility and bacterial endotoxin were carried out. Results:The electroplating mass of 68Zn was (43.71±0.87) mg ( n=35), the yield of 68Ga after irradiation was (10.96±0.67) GBq ( n=35), and the measured half-life was (67.64±0.06) min ( n=7). Only 511 keV energy peak was detected by the gamma spectrometer. After purification, (6.85±0.12) GBq ( n=35) of pure 68Ga was obtained, and the purification efficiency was (62.46±0.96)% (non-attenuated correction, n=35). The metal impurity contents of Zn and Fe were (0.18±0.06) and (1.25±0.43) μg/GBq ( n=5), which met the requirements of European Pharmacopoeia. Three batches of 68Ga-PSMA-11 and 68Ga-DOTATATE were automatically synthesized, with the yield, concentration and radiochemical purity of (3.54±0.14) and (2.74±0.20) GBq, (294.97±11.58) and (228.17±16.32) GBq/L, (99.73±0.11)% and (99.45±0.25)%, respectively. Both sterility and bacterial endotoxin were qualified. Conclusion:High-yield and qualified nuclide 68Ga and 68Ga-labeled drugs are successfully prepared through the low-energy medical cyclotron solid target system and the automated purification and synthesis module, which provide a strong guarantee for clinical practice.
ABSTRACT
In this paper, the domestic and international demand and development trend of clinical diagnostic radionuclides are analyzed, and the medium and high-energy cyclotrons, adequate and systematic facilities, and preparation techniques required for the production of medical radionuclides based on solid targets are introduced. This paper focuses on the research and development carried out by some important medical institutions and scientific research institutes in China over the years in the aspects of medium and high-energy cyclotrons, beam transmission lines, high-power irradiation target stations and new medical isotope production processes etc. It also looks forward to some new directions for the development of medical radionuclides in China during the 14th Five-Year Plan period.