Zhou Liyi, Zhang Xiaobing, Lv Yifan, Yang Chao, Lu Danqing, Wu Yuan, Chen Zhuo, Liu Qiaoling, Tan Weihong
†Molecular Science and Biomedicine Laboratory, State Key Laboratory for Chemo/Bio-Sensing and Chemometrics, College of Chemistry and Chemical Engineering, College of Biology, and Collaborative Research Center of Molecular Engineering for Theranostics, Hunan University, Changsha 410082, China.
‡Department of Chemistry, Department of Physiology and Functional Genomics, Center for Research at Bio/Nano Interface, Shands Cancer Center, University of Florida Genetics Institute and McKnight Brain Institute, University of Florida, Gainesville, Florida 32611-7200, United States.
Anal Chem. 2015 Jun 2;87(11):5626-31. doi: 10.1021/acs.analchem.5b00691. Epub 2015 May 18.
Photoactivatable probe-based fluorescent imaging has become an efficient and attractive technique for spatiotemporal microscopic studies of biological events. However, almost all previously reported photoactivatable organic probes have been based on hydrosoluble precursors, which have produced water-soluble active fluorophores able to readily diffuse away from the photocleavage site, thereby dramatically reducing spatial resolution. Hydroxyphenylquinazolinone (HPQ), a small organic dye known for its classic luminescence mechanism through excited-state intramolecular proton transfer (ESIPT), shows strong light emission in the solid state, but no emission in solution. In this work, HPQ was employed as a precursor to develop a localizable, photoactivatable two-photon probe (PHPQ) for spatiotemporal bioimaging applications. After photocleavage, PHPQ releases a precipitating HPQ fluorophore which shows both one-photon and two-photon excited yellow-green fluorescence, thereby producing a localizable fluorescence signal that affords high spatial resolution for bioimaging, with more than 200-fold one-photon and 150-fold two-photon fluorescence enhancement.
基于光活化探针的荧光成像已成为一种用于生物事件时空显微镜研究的高效且有吸引力的技术。然而，几乎所有先前报道的光活化有机探针都基于水溶性前体，这些前体产生的水溶性活性荧光团能够轻易地从光裂解位点扩散开，从而显著降低空间分辨率。羟基苯基喹唑啉酮（HPQ）是一种以通过激发态分子内质子转移（ESIPT）的经典发光机制而闻名的小型有机染料，它在固态下显示出强烈的发光，但在溶液中不发光。在这项工作中，HPQ被用作前体来开发一种用于时空生物成像应用的可定位、光活化双光子探针（PHPQ）。光裂解后，PHPQ释放出一种沉淀的HPQ荧光团，该荧光团显示出单光子和双光子激发的黄绿色荧光，从而产生一种可定位的荧光信号，为生物成像提供高空间分辨率，单光子荧光增强超过200倍，双光子荧光增强超过150倍。
