多功能纳米CT造影剂的研究进展  

Advances in multifunctional nano-sized CT contrast agents

作　　者：张晓婷[1] 戴志飞[1] 

机构地区：[1]北京大学工学院生物医学工程系,北京100871

出　　处：《科学通报》2015年第35期3424-3437,共14页Chinese Science Bulletin

基　　金：国家杰出青年科学基金(81225011);国家自然科学基金重点项目(81230036)和国家自然科学基金(21273014)资助

摘　　要：计算机断层扫描(CT)具有适用面广、价格相对低廉、高效性和高分辨率等特点,是使用最广泛的无创临床成像技术之一.尽管CT的分辨率远高于传统X射线和其他几种成像技术,但因为成像原理的限制,CT很难分辨软组织的微小变化.为增强软组织的对比度,提高疾病诊断的准确性,人们研制了多种CT造影剂.临床上最早使用的CT造影剂是小分子碘化物,但它们具有毒性和循环时间短的缺点限制了其进一步应用.开发纳米尺寸的造影剂能有效增加循环时间,降低造影剂副作用.除了含碘纳米粒子,基于重金属的纳米粒子,如金、钽、镧系、铋等均可作为高效的CT造影剂.这类新型纳米CT造影剂具有更好生物相容性和更长循环时间,在血管和肿瘤的可视化成像中有十分明显的优势.此外,将CT和其他成像技术,如磁共振成像和超声成像等联合使用,则可以实现优势互补,为临床诊断提供更精确、清晰的图像,为疾病的诊治提供更多个体化诊断信息.考虑到目前疾病诊治,尤其是癌症诊治方面存在的问题,整合了诊断和治疗功能的诊疗一体化制剂更适合临床应用.将CT成像和各种治疗方式结合在一起,即开发基于CT成像的多功能诊疗制剂,可以实现对疾病的实时成像和监控治疗.本文介绍了CT成像的基本原理和当前常用的几种CT造影元素,包括碘、金、铋、钽、镧系元素等,综述了目前多功能纳米CT造影剂的研究现状、发展趋势和面临的问题.Computed tomography（CT） is one of the most widely used noninvasive clinical imaging modalities because of its wide availability,low cost,high efficiency and high resolution. Although the resolution of CT is much higher than that of conventional radiography and many other imaging techniques,it is still difficult to distinguish subtle changes of soft tissues because of physical limitations. To increase the contrast of soft tissues and improve the accuracy of disease diagnosis,a variety of CT contrast agents have been developed. Small iodinated compounds have been widely used as clinical CT contrast agents,but their toxicity and short circulation time restrict their further application. To resolve these problems,nanosized CT contrast agents have been developed. In addition to iodine,nanoparticles based on heavy atoms such as gold,tantalum,lanthanides,and bismuth have been investigated as more efficient CT contrast agents than small iodinated compounds. These novel nanosized CT contrast agents have high biocompatibility and long circulation times,which are advantageous for visualization of blood vessels and tumors. Moreover,the combination of CT with other imaging techniques,such as magnetic resonance imaging and ultrasound imaging,could realize higher sensitivity and more personalized diagnostic information. In particular,theranostic CT contrast agents that integrate diagnosis with therapy in a single nanoplatform may serve as a nanomedicine capable of both noninvasive imaging and remote-controlled therapy. Herein,we introduce the principles of CT imaging and commonly used nanoscale CT contrast elements,including iodine,gold,bismuth,tantalum,and lanthanides. The recent advances,future development and existing problems of multifunctional nanosized CT contrast agents are reviewed.

关 键 词：造影剂 纳米粒子 CT成像 

分 类 号：R981[医药卫生—药品]