Enhancing Intersystem Crossing by Intermolecular Dimer-Stacking of Cyanine as Photosensitizer for Cancer Therapy
CCS CHEMISTRY(2021)
摘要
Development of new photosensitizers (PSs) with high singlet oxygen quantumyield and minimal side effects is of great interest in photodynamic therapy (PDT). Herein, a facile strategy to significantly improve photosensitization has been demonstrated for the first time with two pentamethine dyes connected by a varying alkyl chain resulting in a series of cyanine dimers. The photophysical properties of the dimerswere studied with steady-state optical spectroscopies, a time correlated single photon counting technique, and laser flash photolysis spectrometry. X-ray crystallography confirmed that the molecular packing modes of CyBu-D and Cy-He-D were dominated by H-aggregation. The H-aggregation by dimerization suppresses the radiative singlet decay, which helps to stabilize the highly efficient triplet excitation state. Moreover, the dimers show more intense wavelength absorption in the near-infrared (epsilon 1.5-2.0 times more than monomer Cy-H at 650 nm), better singlet oxygen quantum yield, and a longer triplet-state lifetime than monomer Cy-H, providing excellent performance as a triplet PS. In vivo experiments demonstrated that Cy-He-D successfully suppresses tumor growth after PDT treatment. This work is beneficial to the design of novel heavy atom free PSs for PDT-based theranostic systems. [GRAPHICS] .
更多查看译文
关键词
dimer, intersystem crossing, photodynamic therapy, photosensitizers, cancer
AI 理解论文
溯源树
样例
生成溯源树,研究论文发展脉络
Chat Paper
正在生成论文摘要