Department of Applied Physics, Biomedical and X-ray Physics, KTH Royal Institute of Technology/Albanova, SE 106 91 Stockholm, Sweden.
Contrast Media Mol Imaging. 2018 Dec 27;2018:8174820. doi: 10.1155/2018/8174820. eCollection 2018.
Nanoparticles (NPs) have been used as contrast agents for several bioimaging modalities. X-ray fluorescence (XRF) tomography can provide sensitive and quantitative 3D detection of NPs. With spectrally matched NPs as contrast agents, we demonstrated earlier in a laboratory system that XRF tomography could achieve high-spatial-resolution tumor imaging in mice. Here, we present the synthesis, characterization, and evaluation of a library of NPs containing Y, Zr, Nb, Rh, and Ru that have spectrally matched K-shell absorption for the laboratory scale X-ray source. The K-shell emissions of these NPs are spectrally well separated from the X-ray probe and the Compton background, making them suitable for the lab-scale XRF tomography system. Their potential as XRF contrast agents is demonstrated successfully in a small-animal equivalent phantom, confirming the simulation results. The diversity in the NP composition provides a flexible platform for a better design and biological optimization of XRF tomography nanoprobes.
纳米粒子（NPs）已被用作几种生物成像模式的对比剂。X 射线荧光（XRF）层析成像可以提供对 NPs 的敏感和定量的 3D 检测。使用光谱匹配的 NPs 作为对比剂，我们之前在实验室系统中证明，XRF 层析成像可以在小鼠中实现高空间分辨率的肿瘤成像。在这里，我们介绍了一系列含有 Y、Zr、Nb、Rh 和 Ru 的 NPs 的合成、表征和评估，这些 NPs 的 K 壳层吸收光谱与实验室规模的 X 射线源匹配。这些 NPs 的 K 壳层发射与 X 射线探针和康普顿背景光谱分离良好，使其适合实验室规模的 XRF 层析成像系统。它们在小动物等效体模中的作为 XRF 对比剂的潜力得到了成功验证，证实了模拟结果。NP 组成的多样性为 XRF 层析成像纳米探针的更好设计和生物优化提供了一个灵活的平台。
