Polycyclic naphthalenediimide-based nanoparticles for NIR-Ⅱ fluorescence imaging guided phototherapy

作者:Chuanchao Tang; Chuanhui Song; Zheng Wei; Chen Liang; Jianchuan Ran; Yu Cai*; Xiaochen Dong*; Wei Han*
来源:Science China Chemistry, 2020, 63(07): 946-956.

摘要

Optical imaging and phototherapy in the second near-infrared window(NIR-Ⅱ, 900–1700 nm) can reduce tissue auto-fluorescence and photon scattering, which facilitates higher spatial resolution and deeper tissue penetration depth for solid tumor theranostics. Herein, a polycyclic naphthalenediimide(NDI) based chromophore 13-amino-4,5-dibromo-2,7-di(dodecan-6-yl)-1 H-isoquinolino[4,5,6-fgh]naphtho[1,8-bc][1,9]phenanthroline-1,3,6,8(2H,7H,9H)-tetraone(NDI-NA) was designed and synthesized. With large polycyclic π-systems, NDI-NA molecule possesses broad near-infrared(NIR) absorption(maximum at777 nm) and emission(maximum at 921 nm). By nanoprecipitation, NDI-NA nanoparticles(NPs) were formed in aqueous solution with J-aggregative state, which showed huge red-shift in both absorption spectrum(maximum at 904 nm) and emission spectrum(maximum at 1,020 nm), endowing NDI-NA NPs efficient NIR-Ⅱ fluorescence imaging capability. Besides, the NPs present effective tumor-targeting capability in vivo based on the enhanced permeation and retention(EPR) effect. More importantly, NDI-NA NPs simultaneously have high photothermal conversion efficiency(30.8%) and efficient reactive oxygen species generation ability, making them remarkably phototoxic to cancer cells. The polycyclic chromophore based multifunctional NDI-NA NPs as NIR-Ⅱ phototheranostic agents possess bright future for clinical NIR-Ⅱ imaging-guided cancer phototherapy.