摘要
目的 :探索用99Tcm 直接标记血管抑素 (angiostatin ,AS)的方法 ,并研究标记产物的体外稳定性及其生物活性 .方法 :制备的AS经鉴定后 ,分别用 2 巯基乙醇 (2 ME)和氯化亚锡 (SnCl2 )还原法进行标记 ,并用正交设计筛选最佳合成条件 ;对标记产物用纸层析法及SephadexG 5 0层析柱分离测标记率 ;产物中分别加入牛血清白蛋白 (BSA)、生理盐水及不同摩尔比的半胱氨酸 (Cys)以观察其体外稳定性 ;用人脐静脉内皮细胞系ECV30 4观察其生物活性 .结果 :2 ME法最佳标记条件为AS 1 0 0 μg ,PB(0 .5mol·L-1 ,pH 7.3) 1mL ,2 ME1 0 0 μg,亚甲基二膦酸盐 (MDP) (用 1mL生理盐水溶解 ) 1 0μL ,加入99TcmO4-1 85MBq ,标记率可达 (97.0± 1 .5 ) % ;SnCl2 法为AS 1 0 0 μg ,硼酸缓冲液 (0 .1mol·L-1 ,pH 9.0 ) 1mL ,2 0g·L-1 SnCl2 (1mol·L-1 盐酸作为溶剂 ) 2 0 μL加入MDP药盒 ,用去氧水稀释至 1mL ,取 2 0 μL ,加入99TcmO4-1 85MBq ,标记率可达 (90 .0± 3.0 ) % .产物在体外稳定 ;细胞培养观察其抑制内皮细胞生物活性与AS无显著差异 .结论 :用99Tcm 直接法标记AS简单高效 ,且对AS生物活性无明显影响 .
AIM: To explore the method of 99 Tc m direct labeling of angiostatin (AS) and to investigate the stability and biological activity of 99 Tc m AS in vitro . METHODS: AS was synthesized, validated and then labeled with 99 Tc m after being reduced by 2 ME or SnCl 2. The best synthesis condition was screened by cross design and labeling efficiency was measured by paper chromatography and column chromatography. The stability of 99 Tc m AS was observed by adding BSA, saline and different molar ratios of Cys. The biological activity of 99 Tc m AS was observed in human umbilical vein endothelial cell line CEV304. RESULTS: The labeled efficiency was (97.0±1.5)% for the 2 ME reduced approach. Its best experimental condition was described as below: AS 100 μg, PB(0.5 mol·L -1 , pH 7.3)1 mL, 2 ME 100 μg, MDP (dissolved in 1 mL saline) 10 μL,and 99 Tc mO 4 -185 MBq. The labeled efficiency was (90.0± 3.0)% by use of SnCl 2 reduced method. The best experimental procedure was: AS 100 μg,boric acid buffer (0.1 mol·L -1 , pH 9.0) 1 mL and SnCl 2 (dissolved in 1 mol·L -1 hydrochloric acid) 20 μL were added into MDP, which was diluted with 1ml deoxygenized water. Then 20 μL was taken out and 99 Tc mO 4 - 185 MBq was added. 99 Tc m AS was stable in vitro and had the same biological activity as AS. CONCLUSION: 99 Tc m direct labeling of AS is simple and efficient and the biological activity of 99 Tc m AS has no significant changes compared that of AS.
出处
《第四军医大学学报》
北大核心
2003年第23期2189-2192,共4页
Journal of the Fourth Military Medical University
