Cheng Fei, Qiang Taotao, Li Mingli, Wang Baoshuai, Liu Kun, Li Ke
College of Bioresources and Materials Engineering, Shaanxi Collaborative Innovation Center of Industrial Auxiliary Chemistry & Technology, Shaanxi University of Science & Technology, Xi'an, 710021, China.
College of Pharmacy, Xi'an Medical University, Xi'an, 710021, China.
Chemistry. 2025 Jul 25;31(42):e202501427. doi: 10.1002/chem.202501427. Epub 2025 Jul 7.
Near-infrared (NIR) BODIPY-based photosensitizer NIR-2BDP is constructed through an Fe oxidation strategy. Theoretical calculations and experimental results show that intramolecular charge separation effectively reduces the HOMO-LUMO energy gap, broadens the light absorption range, and suppresses radiative transition (RT) processes. The decrease in the singlet-triplet energy gap enhances the intersystem crossing (ISC) ability of NIR-2BDP (the spin-orbit coupling constant (S→T) is 2.5 times that of NIR-BDP, and the singlet oxygen (O) quantum yield is 2.1 times that of NIR-BDP). The low RT (only 2.2% fluorescence quantum yield) and relatively low triplet generation (11.7% O quantum yield) suggest that NIR-2BDP should have a stronger contribution of nonradiative transition (NRT) processes (and hence a higher photothermal conversion capability). Nanoparticles constructed from NIR-2BDP and DSPE-mPEG exhibit good photothermal conversion efficiency (41.4%) and killing efficiency to tumor cells in the NIR-II window (1000-1700 nm). Therefore, this study extends the sensitization window and improves the NRT ability, paving the way for the construction of multi-functional NIR BODIPY-like photosensitizers.
基于近红外（NIR）硼二吡咯的光敏剂NIR-2BDP是通过铁氧化策略构建的。理论计算和实验结果表明，分子内电荷分离有效地减小了HOMO-LUMO能隙，拓宽了光吸收范围，并抑制了辐射跃迁（RT）过程。单重态-三重态能隙的减小增强了NIR-2BDP的系间窜越（ISC）能力（自旋-轨道耦合常数（S→T）是NIR-BDP的2.5倍，单线态氧（O）量子产率是NIR-BDP的2.1倍）。低RT（荧光量子产率仅为2.2%）和相对较低的三重态生成（O量子产率为11.7%）表明NIR-2BDP应具有更强的非辐射跃迁（NRT）过程贡献（因此具有更高的光热转换能力）。由NIR-2BDP和DSPE-mPEG构建的纳米颗粒在近红外二区窗口（1000 - 1700 nm）表现出良好的光热转换效率（41.4%）和对肿瘤细胞的杀伤效率。因此，本研究扩展了敏化窗口并提高了NRT能力，为构建多功能近红外类硼二吡咯光敏剂铺平了道路。
