Section Biomedical Imaging, Department of Radiology and Neuroradiology, University Medical Center Schleswig-Holstein (UKSH), Kiel University, Kiel, Germany.
Klinik für Mund-, Kiefer- und Gesichtschirurgie, Universitatsklinikum Schleswig-Holstein Campus Kiel, Christian Albrechts Universitat zu Kiel, Germany.
Curr Pharm Des. 2020;26(31):3828-3833. doi: 10.2174/1381612826666200318170849.
Nanoparticle imaging and tracking the release of the loaded material from the nanoparticle system have attracted significant attention in recent years. If the release of the loaded molecules could be monitored reliably in vivo, it would speed up the development of drug delivery systems remarkably.
Here, we test a system that uses indocyanine green (ICG) as a fluorescent agent for studying release kinetics in vitro and in vivo from the lipid iron nanoparticle delivery system. The ICG spectral properties like its concentration dependence, sensitivity and the fluctuation of the absorption and emission wavelengths can be utilized for gathering information about the change of the ICG surrounding.
We have found that the absorption, fluorescence, and photoacoustic spectra of ICG in lipid iron nanoparticles differ from the spectra of ICG in pure water and plasma. We followed the ICG containing liposomal nanoparticle uptake into squamous carcinoma cells (SCC) by fluorescence microscopy and the in vivo uptake into SCC tumors in an orthotopic xenograft nude mouse model under a surgical microscope.
Absorption and emission properties of ICG in the different solvent environment, like in plasma and human serum albumin, differ from those in aqueous solution. Photoacoustic spectral imaging confirmed a peak shift towards longer wavelengths and an intensity increase of ICG when bound to the lipids. The SCC cells showed that the ICG containing liposomes bind to the cell surface but are not internalized in the SCC-9 cells after 60 minutes of incubation. We also showed here that ICG containing liposomal nanoparticles can be traced under a surgical camera in vivo in orthotopic SCC xenografts in mice.
近年来，纳米粒子成像和跟踪负载材料从纳米粒子系统中的释放引起了人们的极大关注。如果能够可靠地监测负载分子的体内释放，将显著加快药物输送系统的发展。
在这里，我们测试了一种使用吲哚菁绿（ICG）作为荧光剂的系统，用于研究体外和体内脂质铁纳米粒子递药系统的释放动力学。ICG 的光谱特性，如浓度依赖性、灵敏度以及吸收和发射波长的波动，可用于收集有关 ICG 周围变化的信息。
我们发现脂质铁纳米粒子中 ICG 的吸收、荧光和光声光谱与纯水中和血浆中的 ICG 光谱不同。我们通过荧光显微镜跟踪含脂质体纳米颗粒的 ICG 进入鳞状癌细胞（SCC）的摄取，并用手术显微镜在原位异种移植裸鼠模型中跟踪 ICG 进入 SCC 肿瘤的摄取。
ICG 在不同溶剂环境（如血浆和人血清白蛋白）中的吸收和发射特性与在水溶液中的特性不同。光声光谱成像证实，当与脂质结合时，ICG 的吸收和发射峰向长波长移动，强度增加。SCC 细胞显示，含 ICG 的脂质体与细胞表面结合，但在孵育 60 分钟后，SCC-9 细胞中未被内化。我们还在这里表明，含有脂质体纳米颗粒的 ICG 可以在体内原位 SCC 异种移植的裸鼠中通过手术相机追踪。
