Department of Chemical and Biomolecular Engineering, National University of Singapore, 4 Engineering Drive 4, Singapore, 117585, Singapore.
Nano-Science Center and Department of Chemistry, University of Copenhagen, Universitetsparken 5, 2100, Copenhagen, Denmark.
Small. 2018 Dec;14(52):e1803325. doi: 10.1002/smll.201803325. Epub 2018 Nov 27.
Efficient organic photosensitizers are attractive for cancer cell ablation in photodynamic therapy. Bright fluorescent photosensitizers are highly desirable for simultaneous imaging and therapy. However, due to fundamental competition between emission and singlet oxygen generation, design attempts to increase singlet oxygen generation almost always leads to the loss of fluorescence. Herein, it is shown for the first time that nanocrystallization enables a simultaneous and significant increase in the brightness and singlet oxygen generation of an organic photosensitizer. Spectroscopic studies show simultaneous enhancement in the visible light absorption and fluorescence after nanocrystallization. The enhanced absorption of visible light in nanocrystals is found to translate directly to the enhanced singlet oxygen production, which shows a higher ability to kill HeLa cells as compared to their amorphous counterpart.
高效的有机光敏剂在光动力疗法中用于癌细胞消融具有吸引力。具有明亮荧光的光敏剂非常适合用于同时成像和治疗。然而，由于发射和单线态氧产生之间的基本竞争，设计尝试增加单线态氧产生几乎总是导致荧光的损失。在此，首次表明纳米晶化为有机光敏剂的亮度和单线态氧产生的同时显著增加提供了可能。光谱研究表明纳米晶化后可见光吸收和荧光同时增强。发现纳米晶体中可见光吸收的增强直接转化为单线态氧产生的增强，这表明与非晶态相比，其具有更高的杀伤 HeLa 细胞的能力。
