RT Journal Article SR Electronic T1 Optimization, automation and validation of [18F]AlF tracer in a custom-made automatic platform with high yield for large scale routine use JF Journal of Nuclear Medicine JO J Nucl Med FD Society of Nuclear Medicine SP 513 OP 513 VO 61 IS supplement 1 A1 Zhiguo Liu A1 Kai Cheng A1 Ming Zhou A1 Li Li YR 2020 UL http://jnm.snmjournals.org/content/61/supplement_1/513.abstract AB 513Objectives: [18F]AlF radiochemistry has been developed as one convenient 18F-labeling strategy with favorable characteristics such as mild labeling conditions, simple purified procedure and multi-patient doses production. However, the commercially available synthesizers were more preferable for 18F nucleophilic fluorination in anhydrous solution at milliliter scale rather than the chelate-based radiolabeling in aqueous solution with small-volumes mixture. To address the problem, we aimed to design and assemble a custom-made automatic platform that was suitable for conducting 18F-AlF radiochelation reliably under small-volume mixture, radiolabeling in one sealed and tight reactor, and SPE based purification. Methods: The hardware of the platform was consisted of commercially available components including one Cavro XCalibur syringe pump, three multi-port switch vales, one heating block and one small-volume reactor showed in Fig.1A. Central control unit (CCU) and software interface on PC desktop were also designed for hardware control and custom-programing. There were three types of the electrical interfaces for the discrete components connection, which include one RS-485 serial interface for Cavro XCalibur syringe pump, 3 Input/output (IO) ports for three switch vales respectively and one connection for temperature control showed in Fig.1B. The platform supporting clinical trial dose production automated general four-step unit operations, including (1) 18F trapping and elution (2) radiolabeling in a small-volume reactor (3) solid phase cartridge purification (4) formulation and sterilization by terminal filtration showed in Fig.1C. Finally, 18F-PSMA-11 and 18F-NOTA-Octreotide, as well as 18F-AlF-Alfatide under clinical investigation (NCT03384511), were produced using this automatic platform. Quality control included radiochemical purity, specific activity, endotoxin test, pH and sterility test. Results: Compared with the complicated architecture of the commercially available synthesizers, the platform we have designed was packed compactly with limited resources . The platform was easy for assembling and the fluid path was simple to configurate even for the operators with no professional experience. The automatic system could realize three work-modes for device controlling including single step operation, unit operation and whole-process automated operation corresponding to the custom-programing. During the past two years, this automatic system has been used in well over more than 50 runs for these 18F-AlF tracers’ productions with only few failures (no more than 5). As shown in Table 1, these 18F-AlF tracers could be produced in large scale for routine use up to18.5 GBq at the end of synthesis (EOS) under the optimized condition, yielding the isolated product in a decay-corrected radiochemical yield of 52±6% for 18F-Alfatide (n=22), 67±6% for 18F-PSMA-11 (n=12) and 45±5% for 18F-NOTA-Octreotide (n=14), respectively. The radiochemical purity was >95% and the specific activity were calculated as 13.2-185.0 GBq/μmol in an overall synthesis time within 30 min. All quality control tests were met for the criteria of the 2015 edition of the Chinese pharmacopoeia for human applications. Conclusions: The platform was simple, affordable and easily configured for 18F-AlF tracers automation . The limited recourses, simple design and low cost reduce the barrier for reproducing the platform. The RCYs were generally higher than those the protocols were operated in commercially available platform, and comparable to those the processes were implemented manually. The production of large radioactivity batches of these tracers would be convenient for multi-patient doses and/or off-site transportation, which increased the potential clinical translations of 18F-AlF radiopharmaceutical. Research Support: This study was partially funded by NSFC 81601554.