Magneto-optical nanoparticles for cyclic magnetomotive photoacoustic imaging.
Magneto-optical nanoparticles for cyclic magnetomotive photoacoustic imaging.
复制标题
DOI：
10.1021/nn5069258
复制
发表时间：
2015-02-24
期刊：
影响因子：
17.1
通讯作者：
Gao X
中科院分区：
文献类型：
--
作者：
Li J;Arnal B;Wei CW;Shang J;Nguyen TM;O'Donnell M;Gao X
光声成像已成为一种非常有前途的工具，可以可视化具有深层组织穿透的分子事件。然而，与大多数其他方式一样，由于来自组织的背景信号，体内条件下的图像对比度远非最佳。使用氧化铁-金核-壳纳米颗粒，我们之前已经演示了磁动光声（mmPA）成像的概念，它能够显着减少背景信号的影响并产生高对比度的分子图像。在这里，我们报告了该技术临床转化的两项重大进展。首先，我们介绍了一类新型紧凑、均匀、磁光耦合的核壳纳米粒子，该纳米粒子是通过聚吡咯（PPy）在氧化铁纳米粒子表面上的局部共聚而制备的。所得的氧化铁-PPy纳米粒子具有高胶体稳定性，解决了金涂层方法之前遇到的光不稳定和小规模合成问题。与此同时，我们开发了具有循环磁运动和超声散斑跟踪（USST）功能的新一代毫米PA，其成像捕获帧率比我们之前演示的光声散斑跟踪（PAST）方法快数百倍。这些进步能够有效消除由生理运动引起的伪影，并证明 mmPA 技术在体内敏感肿瘤成像中的应用。
Photoacoustic imaging has emerged as a highly promising tool to visualize molecular events with deep tissue penetration. Like most other modalities, however, image contrast under in vivo conditions is far from optimal due to background signals from tissue. Using iron oxide–gold core–shell nanoparticles, we have previously demonstrated the concept of magnetomotive photoacoustic (mmPA) imaging, which is capable of dramatically reducing the influence of background signals and producing high-contrast molecular images. Here, we report two significant advances toward clinical translation of this technology. First, we introduce a new class of compact, uniform, magneto-optically coupled core–shell nanoparticles, prepared through localized copolymerization of polypyrrole (PPy) on an iron oxide nanoparticle surface. The resulting iron oxide–PPy nanoparticles feature high colloidal stability and solve the photoinstability and small-scale synthesis problems previously encountered by the gold coating approach. In parallel, we have developed a new generation of mmPA featuring cyclic magnetic motion and ultrasound speckle tracking (USST), whose imaging capture frame rate is several hundred times faster than the photoacoustic speckle tracking (PAST) method we demonstrated previously. These advances enable robust artifact elimination caused by physiologic motions and demonstrate the application of the mmPA technology for in vivo sensitive tumor imaging.