中文摘要：

在冷试验确定最佳反应条件、鉴定反应产物的基础上，对硝基苯乙酮采用亲核法进行^18F标记，经溴代、酯化将标记物与叶酸偶联，生成^18F-叶酸对氟苯乙酮酯，实现叶酸的^18F标记。^18F-叶酸对氟苯乙酮酯与叶酸结合蛋白的结合特性及在荷瘤裸鼠体内的分布结果显示：^18F-叶酸对氟苯乙酮酯能够与叶酸的结合蛋白β-乳球蛋白特异性结合，在荷瘤裸鼠的肿瘤组织有聚集现象。表明合成的。^18F-叶酸对氟苯乙酮酯标记率高、稳定性好，且由于不直接对叶酸分子进行氟标记，避免了高温对结构的破坏。合成的衍生物能够与β-乳球蛋白特异结合。通过肿瘤表面过度表达的叶酸受体介导，浓集于肿瘤组织，用于肿瘤的PET显像。

英文摘要：

This work is aimed at synthesizing an ^18F-labelled folate derivative that can be used as folate-receptorinduced tumor PET imaging agent. Under the optimal reaction and testing specification formulated during the cold-labeling experiments, ^18F labeling of folic acid was achieved in three steps of ^18F pre-labeling, bromination and esterification. The receptor binding property of the newly-synthesized folate radio-derivative was studied through β-lactoglobulin binding test. Tumor-bearing nude mice injected with the new compound were used to study whether the derivative can accumulate within tumor issue. Preliminary studies in vitro and in vivo showed that this new PET agent still possessed receptor binding qualities of folic acid. ^18F-flurophenethyl folate remained good affinity and specificity with β-lactoglobulin. Accumulation of activities in tumor tissues was found in tumor-bearing nude mice. A new folate receptor ligand： ^18F-flurophenethyl folate was synthesized, with high yield and good stability. Since the pre-labeling method was used, the fluorine labeling was not directly imposed upon folic acid. In this way, the structure destruction, which happens in high temperature reaction of folic acid, can be avoided. The synthesized folate derivative remained the binding structural quality of folic acid and could bind with the folate-binding protein： β-lactoglobulin. Through the folate receptors located on tumor tissues, ^18F-flurophenethyl folate accumulated in the tumor tissue, exhibiting its potential as a tumor PET imaging agent.