Ratiometric Molecular Probes Based on Dual Emission of a Blue Fluorescent Coumarin and a Red Phosphorescent Cationic Iridium(III) Complex for Intracellular Oxygen Sensing

Sensors

Toshitada Yoshihara²  Saori Murayama²  Seiji Tobita¹ 

[1] Department of Chemistry and Chemical Biology, Graduate School of Science and Technology, Gunma University, 1-5-1 Tenjin-cho, Kiryu, Gunma 376-8515, Japan;

关键词: oxygen sensor;    fluorescence;    phosphorescence;    iridium complex;    ratiometric probe;    living cells;    imaging;   

DOI  :  10.3390/s150613503

来源: mdpi

【 摘 要 】

Ratiometric molecular probes RP1 and RP2 consisting of a blue fluorescent coumarin and a red phosphorescent cationic iridium complex connected by a tetra- or octaproline linker, respectively, were designed and synthesized for sensing oxygen levels in living cells. These probes exhibited dual emission with good spectral separation in acetonitrile. The photorelaxation processes, including intramolecular energy transfer, were revealed by emission quantum yield and lifetime measurements. The ratios (value of RP2 under hypoxia (2.5% O₂) to that under normoxia (21% O₂) was 1.5 and 1.7 for HeLa and MCF-7 cells, respectively. Thus, the intracellular oxygen levels of MCF-7 cells could be imaged by ratiometric emission measurements using the complex RP2.

【 授权许可】

CC BY   
© 2015 by the authors; licensee MDPI, Basel, Switzerland.