Automated Radiosynthesis and Micro PET/CT Imaging of 18F-FAPI-42

Abstract

Fibroblast activation protein is highly expressed in most epithelial malignant tumors. FAP inhibitor (FAPI) has been used in the early diagnosis of tumors after radionuclide labeling. Objective to achieve automated synthesis and quality control of PET imaging agent 18F-FAPI-42. This study was based on the Allinone synthesizer and its accompanying blank kit, and 18F-FAPI-42 was prepared through one-pot reaction automation. Then, Positron Emission Tomography/Computed Tomography (PET/CT) dynamic imaging was performed on the U87-MG model mouse bearing glioblastoma to evaluate its value. The automated synthesis time of 18F-FAPI-42 was within 60 minutes, with a yield of (15.8±3.2)% (n=10, without decay correction), radiochemical purity than 95%, and specific activity of 14.52 GBq/μmol. micro PET/CT dynamic imaging showed that 18F-FAPI-42 had clear tumor development, long radiation retention time, high tumor to muscle uptake ratio, and activity time curve showed that it was mainly excreted through the kidney. The Allinone synthesizer can stably and efficiently synthesize 18F-FAPI-42 that meets drug quality control standards, and the resulting product quality meets clinical requirements. This synthesis method can provide reference and guidance for 18F labeling of NOTA modified compounds.

Keywords

• fibroblast activation protein
• 18f-fapi-42