Smith Kevin, Getzin Matthew, Garfield Josephine J, Suvarnapathaki Sanika, Camci-Unal Gulden, Wang Ge, Gkikas Manos
Department of Chemistry, University of Massachusetts Lowell, Lowell, MA 01854, USA.
Department of Biomedical Engineering, Rensselaer Polytechnic Institute, Troy, NY 12180, USA.
Nanomaterials (Basel). 2019 Jul 30;9(8):1092. doi: 10.3390/nano9081092.
Lanthanide-based nanophosphors (NPhs) are herein developed as contrast agents for spectral X-ray imaging, highlighting the chemical, macromolecular and structural differences derived from ligand exchange on computed tomography (CT) and solvent dispersibility. Taking advantage of the ability of spectral X-ray imaging with photon-counting detectors to perform image acquisition, analysis, and processing at different energy windows (bins), enhanced signal of our K-edge materials was derived, improving sensitivity of CT imaging, and differentiation between water, tumor-mimic phantoms, and contrast materials. Our results indicate that the most effective of our oleic acid-stabilized K-edge nanoparticles can achieve 2-4x higher contrast than the examined iodinated molecules, making them suitable for deep tissue imaging of tissues or tumors. On the other hand, ligand exchange yielding poly(acrylic acid)-stabilized K-edge nanoparticles allows for high dispersibility and homogeneity in water, but with a lower contrast due to the high density of the polymer grafted, unless further engineering is probed. This is the first well-defined study that manages to correlate NPh grafting density with CT numbers and water dispersibility, laying the groundwork for the development of the next generation CT-guided diagnostic and/or theranostic materials.
基于镧系元素的纳米磷光体（NPhs）在此被开发为光谱X射线成像的造影剂，突出了在计算机断层扫描（CT）上配体交换产生的化学、大分子和结构差异以及溶剂分散性。利用光子计数探测器进行光谱X射线成像在不同能量窗口（区间）进行图像采集、分析和处理的能力，我们的K边材料获得了增强信号，提高了CT成像的灵敏度，以及水、肿瘤模拟体模和造影剂之间的区分度。我们的结果表明，我们最有效的油酸稳定化K边纳米颗粒可以实现比所检测的碘化分子高2-4倍的对比度，使其适用于组织或肿瘤的深部组织成像。另一方面，配体交换产生的聚丙烯酸稳定化K边纳米颗粒在水中具有高分散性和均匀性，但由于接枝聚合物的高密度而具有较低的对比度，除非进行进一步的工程研究。这是第一项成功将NPh接枝密度与CT值和水分散性相关联的明确研究，为下一代CT引导的诊断和/或治疗诊断材料的开发奠定了基础。
