An acceptor–donor–acceptor structured small molecule for effective NIR triggered dual phototherapy of cancer
writer：Zheng He, Linlin Zhao, Qiang Zhang, Meijia Chang, Chenxi Li, Hesheng Zhang, Yan Lu*, Yongsheng Chen*
keywords：Dual phototherapy； PDT
source：期刊
specific source：Adv. Funct. Mater., 2020, 30, 1910301.
Issue time：2020年
Dual phototherapy, including photodynamic therapy (PDT) and
photothermal therapy (PTT), is regarded as a more effective method for
cancer treatment than single PDT or PTT. However, development of single
component and near-infrared (NIR) triggered agents for efficient dual
phototherapy remains a challenge. Herein, a simple strategy to develop
dual-functional small-molecules-based photosensitizers for combined
PDT and PTT treatment is proposed through: 1) finely modulating
HOMO–LUMO energy levels to regulate the intersystem crossing (ISC)
process for effective singlet oxygen (1O2) generation for PDT; 2) effectively
inhibiting fluorescence via strong intramolecular charge transfer (ICT) to
maximize the conversion of photo energy to heat for PTT or ISC process
for PDT. An acceptor–donor–acceptor (A-D-A) structured small molecule
(CPDT) is designed and synthesized. The biocompatible nanoparticles,
FA-CNPs, prepared by encapsulating CPDT directly with a folate
functionalized amphipathic copolymer, present strong NIR absorption,
robust photostability, cancer cell targeting, high photothermal conversion
efficiency as well as efficient 1O2 generation under single 808 nm laser
irradiation. Furthermore, synergistic PDT and PTT effects of FA-CNPs
in vivo are demonstrated by significant inhibition of tumor growth. The
proposed strategy may provide a new approach to reasonably design and
develop safe and efficient photosensitizers for dual phototherapy against
cancer.