Basic Science Investigation
Preparation of Al18F-PSMA-11 and its preliminary PET/CT imaging
Li Rou, Cheng Chao, Mao Juanli, Li Danni, Cui Bin, Li Xiao, Zuo Changjing
Published 2022-10-25
Cite as Chin J Nucl Med Mol Imaging, 2022, 42(10): 602-606. DOI: 10.3760/cma.j.cn321828-20210225-00043
Abstract
ObjectiveTo optimize the preparation conditions and methods of Al18F-prostate specific membrane antigen (PSMA)-11 and evaluate the feasibility of clinical transformation.
MethodsPSMA-N, N′-bis(2-hydroxy-5-(carboxyethy)benzyl)ethylenediamine-N, N′-diacetic acid (HBED-CC) dissolved in CH3COONH4 buffer (pH=4.8) was reacted with AlCl3·3H2O dissolved in pure water at a molar ratio of 1∶1 (60 ℃, 10 min), and then purified by tC18 column and freeze-dried to obtain [Al]-PSMA-11. [Al]-PSMA-11 was labeled by 18F- and the effects of reaction temperature and pH value on the labeling rate were investigated. The labeled products were purified by tC18 column and filtered through sterile filter to obtain Al18F-PSMA-11. The comparison of biodistribution between Al18F-PSMA-11 and 68Ga-PSMA-11 was analyzed on 5 healthy volunteers (age (56±8) years). The differences of SUVmax between two groups were analyzed by independent-sample t test. Besides, the early and delayed imaging of Al18F-PSMA-11 PET/CT were performed on a patient (70 years old) with recurrent prostate cancer for assessment of its potential for prostate cancer recurrence monitoring.
ResultsThe labeling rate was (42.3±3.2)% reacting in aqueous phase (60 ℃, pH=4.8) for 15 min. After being purified with tC18 cartridge, the radiochemical purity of the product was still more than 95% after placement at room temperature for 3 h. Preliminary application demonstrated that there was no significant difference in the biodistribution of Al18F-PSMA-11 and 68Ga-PSMA-11 among lacrimal gland, parotid gland, submandibular gland, liver, spleen, kidney, bladder and part of intestine and SUVmax of targeted organs were also not different (t values: 0.19-1.95, all P>0.05) between two groups. Multiple bone metastases were observed by Al18F-PSMA-11 PET/CT delayed imaging (3 h) in a patient with recurrent prostate cancer.
ConclusionAl18F-PSMA-11 produced with pre-conjugated [Al]-PSMA-11 meets the requirement of the PET imaging application, and it has good potential of localization and imaging for prostate cancer metastatic lesions.
Key words:
Prostatic neoplasm; Prostate-specific membrane antigen; Isotope labeling; Fluorine radioisotopes; Positron-emission tomography; Tomography, X-ray computed
Contributor Information
Li Rou
School of Medical Imaging, Xuzhou Medical University, Xuzhou 221000, China
Cheng Chao
Department of Nuclear Medicine, Shanghai Changhai Hospital, Navy Medical University, Shanghai 200433, China
Mao Juanli
Department of Nuclear Medicine, Shanghai Changhai Hospital, Navy Medical University, Shanghai 200433, China
Li Danni
Department of Nuclear Medicine, Shanghai Changhai Hospital, Navy Medical University, Shanghai 200433, China
Cui Bin
Department of Nuclear Medicine, Shanghai Changhai Hospital, Navy Medical University, Shanghai 200433, China
Li Xiao
Department of Nuclear Medicine, Shanghai Changhai Hospital, Navy Medical University, Shanghai 200433, China
Zuo Changjing
School of Medical Imaging, Xuzhou Medical University, Xuzhou 221000, China
Department of Nuclear Medicine, Shanghai Changhai Hospital, Navy Medical University, Shanghai 200433, China
