To study the synthetic method

quality control and biodistribution of 13 N-ammonia

13 N-NO - 3 and 13 N-NO - 2 were produced from water via the 16 O(p

α) 13 N nuclear reaction with 16.5 MeV proton at 25-30 μA for 10-20 min and then converted to 13 N-ammonia by the Devarda’s alloy. Radiochemical purity was better than 95% as determined by HPLC and TLC. The biodistribution study of 13 N-ammonia in mice indicated that the mean uptake of 13 N-ammonia in myocardium was as high as 19.54%. At the first-pass time

the uptakes of myocardial and lung were (24.90±1.82)% and (22.79±1.94)%

respectiviely

and 92% radioactivity was cleared from blood. After injection

the radioactivity in each organ was significantly readuced at 1 min and was minimum at 5min

but significantly increased at 10min. The uptake of myocardium varied within the range of 11.34-29.24 during 1-30min. High heart-to-liver and heart-to-lung ratios and rapid blood clearance were found. The results suggust that the Devarda’s alloy method is a simple and rapid reducing means for the preparation of 13 N-ammonia. 13 N-ammonia was suitable for clinical regional blood perfusion imaging. PET imaging is suitable at 2-5min after injection.