Acceptor engineering for NIR-II dyes with high photochemical and biomedical performance

• DOI: 10.1038/s41467-022-31521-y
• Publication Date: 2022-07-02T02:03:10Z
• Authors: Aiyan Ji; Hongyue Lou; Chunrong Qu; Wanglong Lu; Yifan Hao; Jiafeng Li; Yuyang Wu; Tonghang Chang; Hao Chen; Zhen Cheng
• Keywords: Acceptor; Quantum yield; Quinoxaline; Electron acceptor; Molecular engineering

It is highly important and challenging to develop donor-acceptor-donor structured small-molecule second near-infrared window (NIR-II) dyes with excellent properties such as water-solubility chem/photostability. Here, we discovery an electron acceptor, 6,7-di(thiophen-2-yl)-[1,2,5]thiadiazolo[3,4-g]quinoxaline (TQT) highest stability in alkaline conditions, compared conventional NIR-II building block benzobisthiadiazole (BBT) 6,7-diphenyl-[1,2,5] thiadiazolo[3,4-g]quinoxaline (PTQ). The sulfonated hydrophilic dye, FT-TQT, further synthesized 2.13-fold increased quantum yield than its counterpart FT-BBT BBT acceptor. FT-TQT complexed FBS also prepared displays a 16-fold increase fluorescence intensity alone. demonstrates real-time cerebral tumor vessel imaging capability µm-scale resolution. Dynamic monitoring of vascular disruption after drug treatment achieved by fluorescent imaging. Overall, TQT efficient acceptor for designing innovative dyes. engineering strategy provides promising approach design next generation fluorophores which open new biomedical applications.