Xu Yongkui, He Ruoyu, Lin Dongdong, Ji Minbiao, Chen Jiyao
State Key Laboratory of Surface Physics and Department of Physics, and Key Laboratory of Micro and Nano Photonic Structures (Ministry of Education), Fudan University, 220 Handan road, Yanpu District, Shanghai 200433, China.
Nanoscale. 2015 Feb 14;7(6):2433-41. doi: 10.1039/c4nr05574h.
A new method to image drug release from drug-nanoparticle composites in living cells was established. The composites of silica coated gold nanorods (AuNR@SiO2) and chlorine e6 (Ce6) photosensitizers (AuNR@SiO2-Ce6) were formed by electrostatic force with a Ce6 loading efficiency of 80%. The strong resonance absorptions of AuNR@SiO2-Ce6 in the near-infrared (NIR) region enabled the effective release of Ce6 from AuNR@SiO2-Ce6 by 780 nm CW laser irradiation. The 780 nm laser beam was applied to not only control the releasing amount of Ce6 from cellular AuNR@SiO2-Ce6 by adjusting the irradiation dose (time), but also to spatially confine the Ce6 release in cells by focusing the laser beam on the target sites. Furthermore, the fluorescence lifetime of Ce6 was found to change drastically from 0.9 ns in the AuNR@SiO2-Ce6 complex to 6 ns after release, and therefore fluorescence lifetime imaging microscopy (FLIM) was introduced to image the photo-induced Ce6 release in living cells. Finally, the controllable killing effect of photodynamic cancer therapy (PDT) using AuNR@SiO2-Ce6 was demonstrated by changing the released amount of Ce6, which indicates that AuNR@SiO2-Ce6 is promising for targeted tumour PDT.
建立了一种对活细胞中药物 - 纳米颗粒复合物的药物释放进行成像的新方法。二氧化硅包覆的金纳米棒（AuNR@SiO₂）与氯e6（Ce6）光敏剂（AuNR@SiO₂ - Ce6）的复合物通过静电力形成，Ce6负载效率为80%。AuNR@SiO₂ - Ce6在近红外（NIR）区域的强共振吸收使得通过780 nm连续波激光照射能有效地从AuNR@SiO₂ - Ce6中释放出Ce6。780 nm激光束不仅可通过调整照射剂量（时间）来控制细胞内AuNR@SiO₂ - Ce6中Ce6的释放量，还可通过将激光束聚焦在目标位点来在空间上限制细胞内Ce6的释放。此外，发现Ce6的荧光寿命从AuNR@SiO₂ - Ce6复合物中的0.9 ns急剧变化到释放后的6 ns，因此引入了荧光寿命成像显微镜（FLIM）来对活细胞中光诱导的Ce6释放进行成像。最后，通过改变Ce6的释放量证明了使用AuNR@SiO₂ - Ce6的光动力癌症治疗（PDT）的可控杀伤效果，这表明AuNR@SiO₂ - Ce6在靶向肿瘤PDT方面具有潜力。
