具有X-射线自显影功能的碘代聚氨酯栓塞剂材料的研究

Radiopaque Iodinated Polyurethane for Embolic Agents

设计合成四碘代双酚A(IBPA)作为扩链剂,以聚丁二酸丁二醇酯(PBS-OH)为软段、异佛尔酮二异氰酸酯(IPDI)和IBPA为硬段,通过偶联反应获得一种新型X-射线聚氨酯显影材料.红外光谱和核磁共振氢谱确定所合成碘代聚氨酯(I-PUs)的结构与组成,并用示差扫描量热法,热重分析,X-射线衍射仪和临床X-射线仪评价不同IBPA含量的碘代聚氨酯的热性能、结晶性和显影效果.结果表明,碘代扩链剂IBPA较高含量的引入对聚合物的热稳定性有一定的影响,并促使聚氨酯由结晶态向非晶态转变.引入IBPA对聚氨酯的显影效果有很好的促进增强作用,聚氨酯材料及微球均具有较好的X光显影效果.噻唑蓝比色法(MTT)评价细胞毒性证实制备的较高碘含量的聚氨酯材料均无细胞毒性,是一种很好的血管栓塞剂材料.

A series of radiopaque iodinated polyurethanes （I-PUs） used for embolic agents were synthesized via coupling reaction between poly（butylene succinate） PBS and iodinated bisphenol-A （IBPA） with varying compositions using isophorone diisocyanate （IPDI）. The IBPA with four iodine atoms per molecule was applied as a chain extender and X-ray contrast agent. The chemical structure and composition of I-PUs were characterized by FTIR and 1H-NMR. The effects of IBPA on crystallization and thermal properties of I-PUs were systematically studied by means of differential scanning calorimetry （DSC） , thermogravimetry analysis （TGA） and wide-angle X-ray diffraction （WAXD）. The results showed that the crystallization behavior and thermal stability were restrained with the introduction of IBPA,which was also confirmed by WAXD. However, in the X-radiography analysis, all the synthesized I-PUs and their microspheres exhibited high radiopacity compared with an aluminum wedge of equivalent thickness. As expected, the X-ray visibility was increased with the iodine content increased. Basic cytotoxicity test was conducted by the method of thiazolyl blue tetrazolium bromide （MTT） colorimetric assay and fluorescent live/dead staining. Cells proliferating well on the polymer- coated coverslips demonstrated that all the synthesized I-PUs were noncytotoxic biomaterials. This study presents a facile synthetic route of radiopaque polyurethanes with high iodine contents,which are expected to possess significantly advantage over the traditional polymer counterparts used for embolic agents and other related biomedical applications.