超声造影微泡:敏锐成像、定点给药与治疗

超声造影剂是一种具有稳定壳层结构的微米级气泡。当受到超声激励时,微泡会随着声波周期性压力变化发生有规律的收缩与膨胀。超声造影剂的引入使得超声成像的分辨力、敏感性和特异性得到极大提升。通过将特异性抗体或配体连接到超声造影剂表面构筑靶向超声造影剂,使超声造影剂主动结合到靶标组织可以实现对病变组织的分子成像。而且,通过在靶向微泡上携带药物或基因可以实现靶向定点治疗。本文首先对超声造影剂的发展历程及制备方法进行了介绍,对超声激励下微泡的声学特性以及新型超声微泡成像方法进行了概述,接着对超声分子影像的原理、靶向微泡制备以及超声分子影像的应用进行了阐述,最后介绍和展望了超声微泡在给药与治疗方面的应用。

Ultrasound Contrast Agents:Sensitive Imaging,Drug Delivery,and Therapy

Ultrasound contrast agents（UCAs） are micron-sized bubbles with a stabilizing shell.Microbubbles work by resonating in an ultrasound beam,rapidly contracting and expanding in response to the pressure changes of the sound wave.The use of UCAs greatly enhances the sensitivity and specificity of ultrasound imaging.Binding specific probes to the microbubbles can achieve affinity to a certain disease specific receptors,and allow targeted ultrasound molecular imaging.Moreover,localization of drug or gene with targeted contrast agents affords the opportunity for targeted drug delivery and gene therapy.The following article reviews the developing process and fabrication method of UCAs,the acoustic properties of UCAs and the imaging methods for their detection,the concept of ultrasound molecular imaging and its application,and the great potential of UCAs in drug delivery and gene therapy.