Factores que influenciam a estabilidade da 18F-FDG

Introduction - The absence of a cyclotron for production of 2-( 18 F)Fluor-2- -deoxy-D-glucose ( 18 F-FDG) is now a reality for most of the centers where Positron Emission Tomography (TEP) exams are held in. It is therefore important to ensure the quality of this radiopharmaceutical from the moment of its synthesis till the administration to the patient. The purpose of this study is to show the influence of the parameters temperature, pH, radioactive concentration (CR) and time in radiochemical purity. Methodology - We analyzed the pH and the radiochemical purity (by thin layer chromatography (TLC)) of six samples of 18 F-FDG with different CR and at different times and temperatures. Results - There was an increase in the percentage of 18 F with time. Nevertheless, results show that samples' dilution decreases the degradation of 18 F-FDG. However, comparing only the diluted samples (185 and 740 MBq / ml), there is a positive relationship between CR and the percentage of 18 F - . There was also an increase in percentage of 18 F at higher temperatures. Conclusion - We advise to dilute the solution and the period of time for storage the 18 F-FDG should not be so long. The samples must have a stable temperature and pH.