Ratiometric fluorescent probes with a self-immolative spacer for real-time detection of β-galactosidase and imaging in living cells

• Published in: Analytica chimica acta 2018-11, Vol.1033, p.193-198
• Main Authors: Chen, Xiangzhu, Ma, Xiaodong, Zhang, Yuanyuan, Gao, Gui, Liu, Jingjing, Zhang, Xueyan, Wang, Mian, Hou, Shicong
• Format: Article
• Language: English
• Subjects: Animals; beta-Galactosidase - analysis; beta-Galactosidase - metabolism; Biocompatibility; Catalysis; Cells, Cultured; Dogs; Endogenous detection; Enzymatic activity; Enzyme activity; Fluorescent Dyes - chemistry; Fluorescent indicators; Galactosidase; High sensitivity; Humans; Madin Darby Canine Kidney Cells - enzymology; Molecular Structure; Optical Imaging; Ovarian cancer; Probes; Radiometry; Ratiometric; Real time; Response time; Self-immolative; Substrates; Time Factors; β-Galactosidase
• ISSN: 0003-2670; 1873-4324
• DOI: 10.1016/j.aca.2018.05.071

Ratiometric fluorescent probes with a self-immolative spacer for β-galactosidase (β-gal) were developed. They function by β-gal-cleaving the β-galactoside bond of fluorescent substrates, followed by self-immolation to liberate the amino group of fluorophore. Thus, a remarkable variation in the photophysical properties was observed and the corresponding ratiometric detection of β-gal was realized. Our studies demonstrated that the GNPN exhibited high sensitivity for recognition of β-gal, with a detection limit as low as 0.17 U L−1. GNPN can rapidly quantify β-gal enzyme activity; the emission ratio F545/F475 for the GNPN reached maxima after approximately 4 min, which was one of the shortest response time ever reported. Furthermore, we demonstrated that these probes possess excellent biocompatibility and can be used to visualize the endogenous β-gal in ovarian cancer cells. [Display omitted] •We developed ratiometric fluorescent probes for detecting β-galactosidase.•The GNPN exhibits a rapid response towards β-galactosidase (4 min) in PBS buffer.•The GNPN exhibits high sensitivity for recognition of β-galactosidase.•These probes are suitable for fluorescence imaging of β-galactosidase in living cells.