Stability and the Improved Methods of ~(18)F-FDG

To study the stability of 18F-FDG with routinely synthesis at high radio-dose and high radioconcentration,18F-FDG was added 0.1% ethanol or repurification by solid-phase extraction for radiolytic 18F-FDG to improve its radiochemical purity(RCP).The results showed that the RCP declined from 99% to 95% within 4 h at 6 TBq/L for room temperature(RT).The radiolysis could be depressed with 0.1% ethanol,the RCP could be over 95% even if the radioactivity concentration was 7.4 TBq/L at RT for 6 h.The repurification method could improve the RCP of 18F-FDG from 80% to 99%.Micro PET/CT imagings of normal rats showed that the vertebra had high uptake with radiolytic 18F-FDG because of impurity.There were no radioactivity uptaking in bone with repuification of 18F-FDG.It indicated that 0.1% ethanol could be used as stabilizers for 18F-FDG to improve the RCP when 18F-FDG had high radio-dose and high radioconcentrtion.The radiolytic 18F-FDG could be repurified by solid-phase extraction to remove the radio-impurity.The method of added 0.1% thanot could be combined with repurification method to assure the RCP of 18F-FDG for over 95% at any given time andradiodose or contcentrayion.