Abstract:
Bright red to NIR emitting cyanine probes 2-3 were synthesized in very good yields. Probes 2-3 exhibited excellent fluorescent quantum yields (ϕfl ≈ 0.1-0.4) and large Stokes shift (Δλ > 150 nm) due to efficient intramolecular charge transfer (ICT) in the conjugated π system. Organelle specificity of these probes was investigated by live cell fluorescence confocal microscopy studies. Probe 3 exhibited the ability to visualize the cell nucleus and mitochondria simultaneously in live cell samples during imaging experiments. However, in structurally modified probe 2 with different substituents (i.e., benzothiazolium vs benzothiazole), the selectivity of the probe switched entirely toward cellular lysosomes. Spectrometric DNA titration experiments were conducted to confirm the DNA/nucleus selectivity of probe 3. The study further evaluates the role of the substituent toward DNA selectivity. Probe 3 was identified as a valuable fluorescent marker to visually identify and study mitochondrial dysfunction in live cells via fluorescent confocal microscopy.
摘要:
以非常好的产率合成了明亮的红色至NIR发射花青探针2-3。由于共轭π系统中有效的分子内电荷转移(ICT),探针2-3表现出优异的荧光量子产率(φfl≈0.1-0.4)和大的斯托克斯位移(Δλ>150nm)。通过活细胞荧光共聚焦显微镜研究研究了这些探针的细胞器特异性。探针3表现出在成像实验期间同时可视化活细胞样品中的细胞核和线粒体的能力。然而,在具有不同取代基的结构修饰探针2中(即,苯并噻唑与苯并噻唑),探针的选择性完全转向细胞溶酶体。进行光谱DNA滴定实验以确认探针3的DNA/核选择性。该研究进一步评估了取代基对DNA选择性的作用。探针3被鉴定为有价值的荧光标记,以通过荧光共聚焦显微镜视觉鉴定和研究活细胞中的线粒体功能障碍。