Radiolabeling of EGCG with 125I and its biodistribution in mice

The aim of the present study was to label EGCG with ¹²⁵I and to determine its radiopharmaceutical potential in mice. EGCG was labeled with ¹²⁵I using the iodogen method. The labeling yield and the radiochemical purity of ¹²⁵I–EGCG were determined by radio thin-layer chromatography (RTLC). The Labeling yield was approximately 89.4 %. The radiochemical purity was approximately 96.4 %. The biodistribution studies of the labeled compound (specific activity; 0.47 TBq/μg) were performed in male Kunming mice. The uptakes of ¹²⁵I–EGCG in some organs were determined at different time after injection to the mice. The radioactivity in each organ was counted and the percentage of injected activity per gram of tissue weight (%ID/g) for each organ and blood was calculated. Incorporation of radioactivity in the various tissue/organ was confirmed by microautoradiography. ¹²⁵I–EGCG uptake in the stomach and salivary gland was higher than other organ/tissue. The black silver grains was concentrated in the nucleus, cytoplasm, intercellular substance and capillaries of that various organs, and its unevenly distributed. Thus, ¹²⁵I–EGCG may be radiopharmaceutical for the imaging of the stomach and salivary gland.