摘要
目的采用^11C-胆碱模块合成^11C-乙酸盐（AC），并研究其在荷瘤鼠体内分布和临床显像效果。方法采用改造过的^11C-胆碱模块合成^11C-AC：^11CO2与1．5mol／L溴化甲基镁在loop环内反应，2ml 1mmol／L乙酸酸化，粗产品经纯化、洗脱、盐酸酸化，再通入氮气除去未反应的^11CO2，以柠檬酸钠中和。荷肺腺癌小鼠于给药后不同时间处死，取血液、心、肝、脾、肺、肾、肌肉及肿瘤，测每克组织百分注射剂量率（％ID／g）。1例经病理检查证实的中分化肝癌患者分别行^18F-脱氧葡萄糖（FDG）和^11C-AC显像。结果^11C-AC的放化产率为（60．5±8．7）％（衰减校正，n=10），放化纯〉98％。从^11CO2到^11C-AC的合成时间为10min。荷肺腺癌鼠的肿瘤／肌肉放射性摄取比值在30min时为1．76。肝癌患者^18F-FDG显像为阴性，而^11C-AC为阳性。结论采用^11C-胆碱模块合成^11C-AC经济、方便，稳定性高，合成放化产率高、放化纯高；能满足临床显像需要。
Objective ^11C-acetate is a useful PET tracer in evaluating myocardial metabolism but more interest has been focused on its application in tumor detection in recent years, especially hepatocellular carcinoma （HCC）. This study was designed to evaluate the laboratory preparation of ^11C-acetate with a modified ^11C-choline commercial module and to investigate its biodistribution in tumor （lung adenocarcinoma）-bearing mice as well as its potential as a tumor imaging agent. Methods ^11C-acetate was synthesized with a modified ^11C choline module： Methyl magnesium bromide Grignard （0.1 ml of 1.5 mol/L） was loaded to a Teflon loop before ^11CO2 was recovered from the target. Carrier acetate solution （2 ml of 1 mmol/L） was pushed through the loop, SPE cartridges （mixed AG50 and IC-Ag） and then the QMA. The loop and cartridges were then rinsed with water. The product ^11C-acetate was then washed out from QMA with 0.9% NaCl solution into a collection vial containing diluted HCl. ^11C-carbonate was removed by nitrogen bubbling for 2 min. After neutralization with trisodium citrate, the injectable ^11C-acetate solution was obtained. The tumor-bearing mice were sacrificed. The percentage activity of injected dose per gram of tissue （% ID/g） for tumor and other tissues were calculated. One patient with known diagnosis of moderately differentiated HCC was injected with ^11C-acetate and imaged by PET/CT, followed by ^18SF-fluorodeoxyglucose （FDG）. Results The synthesis yield of ^11C-acetate was （60.5 ± 8.7 ）% （decay corrected, n = 10） ; the radiochemistry purity was 〉 98% and the synthesis time was 10 min from ^11CO2 to ^11C-acetate. The radioactivity ratio for tumor/muscle was 1.76 at 30 min. A patient with known HCC showed positive ^11C-acetate accumulation in the tumor but was negative in is F-FDG. Conclusion The synthesis of ^11C-acetate by modification of an ^11C-choline commercial module was feasible and it could be achieved with high yield, high radiochemical purity and with more stable operation.
出处
《中华核医学杂志》
CAS
CSCD
北大核心
2008年第5期319-322,共4页
Chinese Journal of Nuclear Medicine
基金
基金项目：国家自然科学基金重点课题（60331010）
