ABSTRACT
The introduction of 2-[18F] fluor-2-deoxy-D-glucose (18FDG) has provided a valuable tool for the study of glucose metabolism in both normal and diseased tissue in conjunction with positron emission tomography (PET). 18FDG is the most important radiopharmaceutical to be used in Nuclear Medicine for studying the brain, heart and tumor. The advancement in synthesis and quality control of 18FDG and its approval by US FDA are main reasons for increasing clinical application of 18FDG over the last 20 years. In this manuscript we explain the synthesis, quality control and stability studies of 18FDG (evaluate the physicochemical and microbiological stability of 18FDG, stored at room temperature (18 - 23 °C), and 35 - 40 °C, at different time intervals). We investigated how the influence of environmental factors in different lengths of time, alters the quality of this radiopharmaceutical. The pH, radionuclidic identity and purity, radiochemical identity and purity, chemical purity, bacterial endotoxins and sterility of 18FDG were evaluated according to the European Pharmacopoeia 7ed. analytical methods and acceptance criteria. The results suggest that under experimental conditions 18FDG has physicochemical and microbiological stability up to 10 h after the end of synthesis.
ABSTRACT
Improvements in the two-step synthesis of 1,1,1,3,3,3-hexafluoro-2- (fluoromehoxy)propane (Sevoflurane) that result in the product cost reduction, safety level enhancement and positive environmental impacts are described. This process consists of chloromethylation reaction of 1,1,1,3,3,3-hexafluoro-2-propanol (HFIP) followed by a halogen-exchange fluorination. This is the first synthesis of Sevoflurane in Iran which was successfully scaled up. During this work, several improvements have been achieved by optimization of the reaction time, the amount of consumed starting materials and solvents and work up procedure while keeping the yield and purity intact. The reaction time of the first step (24 h) was diminished to 4 h. (19)F NMR spectroscopy was used to investigate the rate of the reaction in the first step and to evaluate the influence of different parameters mentioned on the achieved improvements.
