Twisted BODIPY derivative: intersystem crossing, electron spin polarization and application as a novel photodynamic therapy reagent
Twisted BODIPY derivative: intersystem crossing, electron spin polarization and application as a novel photodynamic therapy reagent
复制标题
扭曲的BODIPY衍生物：系间窜越、电子自旋极化及其作为新型光动力治疗试剂的应用
DOI：
10.1039/d1cp00948f
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发表时间：
2021-03-10
影响因子：
3.3
通讯作者：
Fedin, Matvey
中科院分区：
文献类型：
--
作者：
Dong, Yu;Kumar, Prashant;Fedin, Matvey
研究了一种无重原子、具有扭曲π共轭骨架的BODIPY衍生物的电子物理性质。有效的系间交叉（ISC量子产率：56%）和一个异常长寿的三重态观察（4.5毫秒在固体聚合物膜矩阵和197.5亩在溶液中）。时间分辨电子顺磁共振（TREPR）谱和密度泛函理论（DFT）计算证实了三重态在整个扭曲π共轭骨架上的离域和零场分裂（zero-field-splitting，DFD）D参数D =-69.5mT，小于2，6-diiodoBODIPY的DFD =-104.6mT。扭曲BODIPY的三重态TREPR谱的电子自旋极化（ESP）相位图为（a，a，e，a，e，e），与2，6-二碘BODIPY的（e，e，e，a，a，a）不同，表明扭曲结构ISC的电子自旋选择性与自旋轨道耦合效应的电子自旋选择性不同。根据计算得到的自旋轨道耦合矩阵元（0.154-1.964 cm（-1）），结合S-1/T-n态的匹配能量，提出ISC是通过S-1 → T-2/T-3发生的.计算结果与TREPR关于电子自旋选择性（T-1态的T-Y子能级的过布居）的结果一致。扭曲BODIPY的长寿命三重态的优点通过其有效的单线态氧（O-1（2））光敏化（phi（Delta）= 50.0%）证明，即使在严重缺氧气氛（pO（2）= 0.2%，v/v）下。观察到扭曲BODIPY的高光毒性（EC 50 = 1.0 μ M）和低暗毒性（EC 50 = 78.5 μ M），因此细胞研究证明其作为新型有效的无重原子光动力治疗（PDT）剂的潜力。
The photophysical properties of a heavy atom-free BODIPY derivative with a twisted pi-conjugated framework were studied. Efficient intersystem crossing (ISC quantum yield: 56%) and an exceptionally long-lived triplet state were observed (4.5 ms in solid polymer film matrix and 197.5 mu s in solution). Time-resolved electron paramagnetic resonance (TREPR) spectroscopy and DFT computations confirmed the delocalization of the triplet state on the whole twisted pi-conjugated framework and the zero-field-splitting (ZFS) D parameter of D = -69.5 mT, which is smaller than that of 2,6-diiodoBODIPY (D = -104.6 mT). The electron spin polarization (ESP) phase pattern of the triplet state TREPR spectrum of the twisted BODIPY is (a, a, e, a, e, e), which is different from that of 2,6-diiodo BODIPY (e, e, e, a, a, a), indicating that the electron spin selectivity of the ISC of the twisted structure is different from that of the spin orbital coupling effect. According to the computed spin-orbit coupling matrix elements (0.154-1.964 cm(-1)), together with the matched energy of the S-1/T-n states, ISC was proposed to occur via S-1 -> T-2/T-3. The computational results were consistent with TREPR results on the electron spin selectivity (the overpopulation of the T-Y sublevel of the T-1 state). The advantage of the long-lived triplet state of the twisted BODIPY was demonstrated by its efficient singlet oxygen (O-1(2)) photosensitizing (phi(Delta) = 50.0%) even under a severe hypoxia atmosphere (pO(2) = 0.2%, v/v). A high light toxicity (EC50 = 1.0 mu M) and low dark toxicity (EC50 = 78.5 mu M) were observed for the twisted BODIPY, and thus the cellular studies demonstrate its potential as a novel potent heavy atom-free photodynamic therapy (PDT) agent.