Self-reporting hypoxia-responsive supramolecular phototheranostic nanomaterials based on AIEgen and azocalixarene

• DOI: 10.1007/s11426-024-2301-3
• Publication Date: 2025-01-09T08:09:27Z
• Authors: Xiao-Wen Han; Guo-Ling Zhang; Pu Chen; Jing Zhang; Guogang Shan; Chunxuan Qi; Ben Zhong Tang; Hai-Tao Feng
• Keywords: Nanomaterials; Hypoxia

Hypoxia is a significant feature in most of solid tumors and developing hypoxia-responsive phototheranostic system is still a challenge. In this contribution, a supramolecular assembly strategy based on sulfonate-functionalized azocalix[4]arene (SAC4A) and cationic aggregation-induced emission photosensitizer (namely TPA-H) was proposed for hypoxia-responsive bioimaging and photodynamic therapy (PDT). Upon supramolecular complexation of TPA-H and SAC4A through electrostatic interaction, the fluorescence and reactive oxygen species (ROS) generation of TPA-H were largely inhibited. In hypoxic tumors, the azo group of SAC4A can be reduced to aniline derivative and release the included TPA-H to recover its pristine fluorescence and ROS. Interestingly, the free TPA-H undergoes cell membrane-to-mitochondria translocation during cell imaging, achieving a real-time self-reporting PDT system. In vivo tumor imaging and therapy reveal that this as-prepared supramolecular complexes have good biosafety and efficient antitumor activity under hypoxia. Such hypoxia-responsive supramolecular photosensitizer system will enrich image-guided PDT.