中文摘要：

目的：制备叶酸偶联人血清清蛋白（Mate—HSA）。方法：利用叶酸活性酯与清蛋白纳米粒表面的氨基反应，制得叶酸偶联清蛋白纳米粒。采用葡聚糖凝胶柱色谱法及紫外分光光度法验证偶联是否成功，并测定叶酸偶联的程度。结果：通过葡聚糖凝胶柱色谱法使叶酸偶联清蛋白纳米粒与未反应的叶酸活性酯完全分离，采用2,4，6－三硝基苯磺酸显色法测得HSA的表面活性氨基的含量为168μg／mgHSA，则偶联于HSA表面的叶酸密度为27．26％。结论：叶酸偶联人血清清蛋白制备成功，为下一步实验奠定了基础。

英文摘要：

Objective： To prepare folate-conjugated human serum albumin （folate-HSA）. Methods： The activated folic acid was conjugated to the surface of HSA via the amino groups to form folate-HSA. Folate-HSAs were purified with Sephadex G250 column and the extent of folate-HSA was measured by quantitative ultraviolet spectrophotometric analysis in order to verify whether the activated folic acid was conjugated to the surface of HSA. Results： The folate-HSAs were completely separated from unreacted folic acid with Sephadex G250 column. The surface activity amino was measured by 2,4,6-trinitro-benzene-sulfonic acid coloration method （TNBS） and its content was 168 μg/mg HSA, so the density of folic acid conjugated to the surface of HSA was 27.26%. Conclusion： The folic acid conjugated to the surface of HSAs is successfully prepared, which will establish a good base for the following experiments.