Laboratory for Molecular Photonics, Departments of Biology and Chemistry , University of Miami , 1301 Memorial Drive , Coral Gables , Florida 33146-0431 , United States.
Grup de Materials Orgànics, Institut de Nanociència i Nanotecnologia (IN2UB), Departament de Química Inorgànica i Orgànica (Secció de Química Orgànica) , Universitat de Barcelona , Martí i Franqués 1 , E-08028 , Barcelona , Spain.
ACS Sens. 2018 Jul 27;3(7):1347-1353. doi: 10.1021/acssensors.8b00262. Epub 2018 Jun 21.
A mechanism to photoactivate far-red/near-infrared fluorescence with infinite contrast and under mild visible illumination was designed around the photophysical properties of borondipyrromethene (BODIPY) dyes and the photochemical behavior of oxazine heterocycles. Specifically, the photoinduced and irreversible cleavage of an oxazine ring with a laser line at 405 nm extends the electronic conjugation of a BODIPY chromophore over a 3 H-indole auxochrome with a 2-(4-methoxyphenyl)ethenyl substituent in position 5. This structural transformation shifts bathochromically the main absorption band of the BODIPY component to allow the selective excitation of the photochemical product with a laser line of 633 nm and produce fluorescence between 600 and 850 nm. This combination of activation, excitation, and emission wavelengths permits the visualization of the cellular blastoderm of developing Drosophila melanogaster embryos with optimal contrast and essentially no autofluorescence from the biological specimen. Furthermore, the sequential acquisition of images, after the photoactivation event, enables the tracking of individual cells within the embryos in real time. Thus, our structural design and operating principles for the photoactivation of far-red/near-infrared fluorescence can evolve into invaluable probes to monitor cellular dynamics in vivo.
设计了一种基于硼二吡咯甲川（BODIPY）染料的光物理性质和恶嗪杂环的光化学反应行为的远红/近红外光荧光光激活机制，其具有无限对比度，并在温和的可见光照射下进行。具体来说，通过在 405nm 激光线照射下，恶嗪环的光诱导和不可逆断裂，将具有 2-(4-甲氧基苯基)乙烯基取代基的 3H-吲哚助色团的电子共轭延伸到 BODIPY 生色团上。这种结构转变使 BODIPY 组件的主要吸收带红移，从而允许用 633nm 的激光线选择性地激发光化学反应产物，并产生 600nm 至 850nm 之间的荧光。这种激活、激发和发射波长的组合允许用最佳对比度可视化发育中的黑腹果蝇胚胎的细胞原肠胚，并且基本上没有来自生物样本的自发荧光。此外，在光激活事件后，顺序获取图像，可以实时跟踪胚胎内的单个细胞。因此，我们的远红/近红外荧光光激活的结构设计和操作原理可以发展成为监测体内细胞动力学的宝贵探针。
