Synthesis of podo-and epipodo-11C-podophyllotoxin and their biodistribution in mouse bearing EMT6 tumor / 中华核医学与分子影像杂志

ABSTRACT

Objective To synthesize podo-and epipodo-podophyllotoxin labeled with 11C and investigate their biodistribution in mice bearing EMT6 tumor by microPET.Methods 11 C-podo-or epipodopodophyllotoxin was synthesized by 11 C-CH3-Triflate mixed with 4'-methyl-demethmyl-podophyllotoxin (podo-and epipodo-) and purified using HPLC.The radiochemical purity (RCP) was analyzed by HPLC.Thirty mice bearing EMT6 tumor were divided into 2 groups and injected with 3.7 MBq 11C-podo-or epipodo-podophyllotoxin.The biodistribution of 11C-podo-or epipodo-podophyllotoxin was evaluated with microPET.The ID％/g was calculated.Paired t test was used to analyze the data.Results The yields of 11C-podo-and epipodo-podophyllotoxin were both ＞90％.The RCP was ＞99％.The biodistribution of 11C-podo-and epipodo-podophyllotoxin was similar with slow blood clearance and high uptake in abdomen.The tumor uptake of 11C-epipodophyllotoxin and 11C-podophyllotoxin at 30 min was (3.63±0.98) ％ID/g and (3.16±0.27) ％ID/g,respectively.The uptake ratio of tumor to blood and to muscle was 0.68 vs 0.62 and 1.52 vs 1.22,respectively.There was no significant difference between the tumor uptake of the two agents (t=0.47,P＞0.05).The result of microPET imaging was consistent with that of mice experiment.Conclusion 11C-podophyllotoxin has limited clinical value for tumor imaging.