Surface-ligand effect on radiosensitization of ultrasmall luminescent gold nanoparticles.
Surface-ligand effect on radiosensitization of ultrasmall luminescent gold nanoparticles.
复制标题
DOI：
10.1142/s1793545816420037
复制
发表时间：
2016-07
影响因子：
2.5
通讯作者：
Zheng J
中科院分区：
文献类型：
--
作者：
Jiang X;Du B;Yu M;Jia X;Zheng J
金纳米粒子（AuNPs）具有良好的生物相容性和高Z材料特性，可作为潜在的放射增敏剂;然而，由于AuNPs的体内外行为不仅取决于其粒径，还取决于其表面化学性质，因此，表面配体是否影响其放射增敏作用的研究很少。通过对两种分别用两性离子谷胱甘肽和中性聚乙二醇（PEG）配体包覆的超小（~2 nm）近红外（NIR）发射金纳米颗粒的放射增敏性进行头对头比较，我们发现两性离子型谷胱甘肽包被的金纳米颗粒（GS-AuNPs）在低剂量（~2.25戈伊）的兆伏级光子束照射下可降低MCF-7细胞的存活率。另一方面，PEG-AuNPs可以作为辐射防护剂，使MCF-7细胞对辐射更具抵抗力，清楚地表明表面化学在AuNPs的辐射增敏中的关键作用。更详细的研究表明，这种差异是独立的细胞摄取及其效率，但可能与配体诱导的光电子产生和/或金纳米粒子和X射线触发的活性氧（ROS）之间的相互作用的差异。
Gold nanoparticles (AuNPs) could serve as potential radiotherapy sensitizers because of their exceptional biocompatibility and high-Z material nature; however, since in vitro and in vivo behaviors of AuNPs are determined not only by their particle size but also by their surface chemistries, whether surface ligands can affect their radiosensitization has seldom been investigated in the radiosensitization of AuNPs. By conducting head-to-head comparison on radiosensitization of two kinds of ultrasmall (~2 nm) near-infrared (NIR) emitting AuNPs that are coated with zwitterionic glutathione and neutral polyethylene glycol (PEG) ligands, respectively, we found that zwitterionic glutathione coated AuNPs (GS-AuNPs) can reduce survival rates of MCF-7 cells under irradiation of clinically used megavoltage photon beam at low dosage of ~2.25 Gy. On the other hand, PEG-AuNPs can serve as a radiation-protecting agent and enabled MCF-7 cells more resistant to the irradiation, clearly indicating the key role of surface chemistry in radiosensitization of AuNPs. More detailed studies suggested that such difference was independent of cellular uptake and its efficiency, but might be related to the ligand-induced difference in photoelectron generation and/or interactions between AuNPs and X-ray triggered reactive oxygen species (ROS).