Sheehan Aimee, Okkelman Irina A, Groslambert Geoffrey, Bucher Christophe, Dmitriev Ruslan I, Filatov Mikhail A
School of Chemical and Biopharmaceutical Sciences, Technological University Dublin, City Campus, Grangegorman, Dublin 7, Ireland.
Tissue Engineering and Biomaterials Group, Department of Human Structure and Repair, Faculty of Medicine and Health Sciences, Ghent University, The Core, C. Heymanslaan 10, 9000, Ghent, Belgium.
Chemistry. 2025 Feb 17;31(10):e202404188. doi: 10.1002/chem.202404188. Epub 2025 Jan 10.
Donor-acceptor BODIPY dyads, functionalized at the 2 and 6 positions with benzyl ester (BDP-DE) or carboxylic acid (BDP-DA) groups, were synthesized, and their optoelectronic properties were investigated. Carbonyl groups were found to increase the reduction potential of the BODIPY core by 0.15-0.4 eV compared to regular alkyl-substituted BODIPYs. These compounds exhibited efficient intramolecular charge separation and triplet state formation through the spin-orbit charge transfer intersystem crossing (SOCT-ISC) process, achieving singlet oxygen quantum yields of up to 92 %, depending on the solvent polarity. Notably, the fluorescence and singlet oxygen generation of BDP-DAs were found to depend on the ionization state of the carboxylic groups. Time-resolved fluorescence measurements revealed that complexation of BDP-DAs with bovine serum albumine (BSA) significantly extended their excited state lifetimes. Fluorescence lifetime imaging microscopy (FLIM) studies of human colorectal carcinoma (HCT116) cells and pig small intestinal organoids (enteroids) provided insights into subcellular localization. The diacid with 2,4-dimethoxyphenyl group at the meso-position (DA1) displayed longer lifetimes in lipid-droplet-like structures and shorter lifetimes in cytoplasmic regions. The diacid containing a meso-anthracenyl group (DA2) formed 'islands' in cell monolayers, exhibiting a distinct lifetime gradient from the periphery to the center. These results highlight the potential of donor-acceptor BODIPYs as fluorescent probes for biological imaging, particularly in revealing subtle differences in cellular environments.
合成了在2位和6位用苄酯（BDP-DE）或羧酸（BDP-DA）基团功能化的供体-受体硼二吡咯二元化合物，并研究了它们的光电性质。发现与常规烷基取代的硼二吡咯相比，羰基可使硼二吡咯核心的还原电位提高0.15 - 0.4 eV。这些化合物通过自旋轨道电荷转移系间窜越（SOCT-ISC）过程表现出有效的分子内电荷分离和三重态形成，根据溶剂极性，单线态氧量子产率高达92%。值得注意的是，发现BDP-DA的荧光和单线态氧生成取决于羧基的电离状态。时间分辨荧光测量表明，BDP-DA与牛血清白蛋白（BSA）的络合显著延长了它们的激发态寿命。对人结肠直肠癌（HCT116）细胞和猪小肠类器官（肠类细胞）的荧光寿命成像显微镜（FLIM）研究提供了亚细胞定位的见解。在中位带有2,4-二甲氧基苯基的二酸（DA1）在脂滴样结构中显示出较长的寿命，而在细胞质区域中寿命较短。含有中位蒽基的二酸（DA2）在细胞单层中形成“岛”，从周边到中心呈现出明显的寿命梯度。这些结果突出了供体-受体硼二吡咯作为生物成像荧光探针的潜力，特别是在揭示细胞环境中的细微差异方面。
