Biocompatible Nitro Group-Based Photosensitizer for AIE, Hypoxia, and Photodynamic Therapy. Experimental and...

Photodynamic therapy (PDT), which relies on the production of reactive oxygen species (ROS) induced by a photosensitizer to kill cancer cells, has become a non-invasive approach to combat cancer. However, the conventional aggregation-caused quenching effect, as well as the low ROS generation ability of photosensitizers, restricts their biological applications. Herein, we described the design and synthesis of MAN-NO₂, a novel nitro-based chalcone and investigate with aggregation induced emission (AIE), HUMO-LUMO, and cellular imaging properties. MAN-NO₂ exhibited AIE in acetonitrile-water mixture and this was confirmed by fluorescence spectroscopy studies. The compound MAN-NO₂ was investigated by computational analysis in which their HUMO-LUMO, optimized geometry, ELF-π values, LOL-π, and pi-pi-stacking are included. The synthesized AIE compound MAN-NO₂ was found to be non-toxic and promising candidate for biological studies. Cell imaging experiments reveals that MAN-NO₂ can effectively enhance the signal-to-noise ratio of imaging by reducing the interference from background due to their impressive AIE characteristics. In HeLa cells, MAN-NO₂ showed notable oxygen responses in hypoxia and normoxia. Compound MAN-NO₂ was discovered to have outstanding qualities as intracellular oxygen probes. This work will provide guidance for the construction of biological applications on the base of AIE-active compounds, which offers multiple opportunities for multiple clinical applications under hypoxic conditions.