A single contrast agent that offers whole-body non-invasive imaging along with the superior sensitivity and spatial resolution of surface-enhanced resonance Raman scattering (SERRS) imaging would allow both pre-operative mapping and intraoperative imaging and thus be highly desirable. We hypothesized that labeling our recently reported ultrabright SERRS nanoparticles with a suitable radiotracer would enable pre-operative identification of regions of interest with whole body imaging that can be rapidly corroborated with a Raman imaging device or handheld Raman scanner in order to provide high precision guidance during surgical procedures. Here we present a straightforward new method that produces radiolabeled SERRS nanoparticles for combined positron emission tomography (PET)-SERRS tumor imaging without requiring the attachment of molecular chelators. We demonstrate the utility of these PET-SERRS nanoparticles in several proof-of-concept studies including lymph node (LN) tracking, intraoperative guidance for LN resection, and cancer imaging after intravenous injection. We anticipate that the radiolabeling method presented herein can be applied generally to nanoparticle substrates of various materials by first coating them with a silica shell and then applying the chelator-free protocol.

中文翻译：

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SERRS纳米粒子的无螯合放射标记用于全身PET和术中拉曼成像

提供全身非侵入性成像以及表面增强共振拉曼散射（SERRS）成像的卓越灵敏度和空间分辨率的单一造影剂将允许术前作图和术中成像，因此非常需要。我们假设，使用合适的放射性示踪剂标记我们最近报道的超亮SERRS纳米颗粒，将可以通过全身成像进行术前识别，该区域可以通过拉曼成像设备或手持式拉曼扫描仪快速确认，从而在手术过程中提供高精度指导外科手术。在这里，我们提出了一种简单的新方法，该方法可产生放射性标记的SERRS纳米颗粒，用于组合正电子发射断层扫描（PET）-SERRS肿瘤成像，而无需连接分子螯合剂。我们在几个概念验证研究中证明了这些PET-SERRS纳米粒子的效用，包括淋巴结（LN）追踪，LN切除术的术中指导以及静脉注射后的癌症成像。我们预期，通过首先用二氧化硅壳涂覆它们，然后应用无螯合剂方案，可以将本文提出的放射性标记方法通常应用于各种材料的纳米颗粒基质。静脉注射后进行癌症成像。我们期望通过首先用二氧化硅壳涂覆它们，然后应用无螯合剂方案，可以将本文提出的放射性标记方法通常应用于各种材料的纳米颗粒基质。静脉注射后进行癌症成像。我们期望通过首先用二氧化硅壳涂覆它们，然后应用无螯合剂方案，可以将本文提出的放射性标记方法通常应用于各种材料的纳米颗粒基质。