一种磁共振造影剂前体BSA-(Gd-DTPA)n的制备、表征及体内外评价  

Synthesis,Characterization and Evaluation of BSA-(Gd-DTPA)n as a MRI Contrast Agent Precursor

作　　者：李树平[1,2] 冯晓源[1] 梁春敏[3] 何慧瑾[1] 孟庆刚[4] 占昌友[4] 李瑾[4] 顾炳[4] 佘振珏[3] 邱龙华[1] 杨波[2] 陈路平 

机构地区：[1]复旦大学附属华山医院放射科 [2]中国人民解放军第四五五医院 [3]复旦大学医学院 [4]复旦大学药学院 [5]上海纽迈电子科技有限公司

出　　处：《中国医学计算机成像杂志》2010年第1期46-51,共6页Chinese Computed Medical Imaging

基　　金：卫生部卫生行业科研专项项目(项目编号:200802099)资助~~

摘　　要：目的:改进BSA-(Gd-DTPA)n制备及纯化方法,探讨其作为磁共振造影剂前体的优势及应用前景。方法:BSA与二乙烯三胺五乙酸环酐反应生成BSA-(DTPA)n,并与GdCl3螯合生成BSA-(Gd-DTPA)n。紫外光谱法鉴定其结构,并定量测定其中DTPA对BSA的偶联率。测定配合物体外弛豫时间T1、T2,分析其弛豫性能R1、R2。小鼠急性毒性试验评价药物安全性。大鼠磁共振增强扫描评价其活体内代谢及分布情况。结果:本研究制得的BSA-(Gd-DTPA)n配合物中n=26。体外弛豫性能R1约为7.00×10-3L.mmol-1.ms-1,比小分子Gd-DTPA的弛豫性能(3.52×10-3L.mmol-1.ms-1)提高近1倍。大鼠磁共振增强扫描显示BSA-(Gd-DTPA)n和白蛋白一样具有长循环特性。结论:本实验改进方法可制备出磁共振造影剂前体BSA-(Gd-DTPA)n,该配合物具备长循环特性,且具有多个可供修饰的氨基,可作为一种潜在的磁共振造影剂前体。Purpose： To improve the synthesis and purification methods of BSA - （Gd - DTPA）n, and to explore its advantages and application prospect as a high - performance relaxation magnetic resonance imaging agent precursor. Methods： Bovine serum albumin （BSA） reacted with diethylenetriamine pen- taacetic acid cyclic anhydride （DTPACA） under the condition pH = 9, and produced the conjugate BSA - （DTPA）n, GdCl3 was further chelated to the conjugate to produce BSA - （Gd - DTPA）,. BSA - （Gd - DT- PA） , was characterized and identified by UV spectroscopy . The coupling ratio of DTPA and BSA was quantitatively determined by ICP/AES. The relaxation rates of R1/R2 were further analyzed by measuring the relaxation time TI/ T2 of the complex in vitro. The drug safety was evaluated by acute toxicity test. The preliminary evaluation of its metabolism and distributions in vivo was done by magnetic resonance multi - phase enhanced scanning for multi - organs in rats. Results： In the obtained complex BSA - （Gd- DTPA） n, n = 26. The relaxation property R1 in vitro was about 7.00×10-3L·mmol^-1·ms^-1 at 0.5T in 32℃, about twice of the relaxation property of the small - molecule Gd - DTPA（3.52 ×10-3L·mmol^-1·ms^-1）. The enhanced MRI scans in SD rats showed that vessels were obviously enhanced at the same time that the renal pelvis already had been filled by the contrast agent. This indicated that BSA- （Gd- DTPA）n had notable long - circulating characteristic as albumin, and this was conducive to its fully integration with the targeted lesions and displaying the vessels.Conclusion： The high relaxation performance magnetic resonance contrast agent precursor BSA- （Gd- DTPA）n can be prepared and purified by the improved methods in this experiment, it has notable long - circulating characteristic, and has many amino- groups for modification , so it can be used as a potential MRI targeting contrast agent precursor.

关 键 词：磁共振造影剂前体 合成 表征 BSA-(Gd—DTPA)n 

分 类 号：R445.2[医药卫生—影像医学与核医学] R914[医药卫生—诊断学]