A novel near-infrared fluorescent probe for sensitive detection of β-galactosidase in living cells

Abstract

A novel near-infrared fluorescent probe for β-galactosidase has been developed based on a hemicyanine skeleton, which is conjugated with a D-galactose residue via a glycosidic bond. The probe serves as a substrate of β-galactosidase and displays rapid and sensitive turn-on fluorescent responses to β-galactosidase in aqueous solution. A 12.8-fold enhancement of fluorescence intensity at 703 nm was observed after incubation of 10 nM of β-galactosidase with 5 μM probe for 10 min. The probe can sensitively detect as little as 0.1 nM of β-galactosidase and shows linear responses to the enzyme concentration below 1.4 nM. The kinetic study showed that the probe has high binding affinity to β-galactosidase with Km = 3.6 μM. The probe was used to detect β-galactosidase in living cells by employing the premature cell senescence model. The probe exhibited strong fluorescent signals in senescent cells but not in normal cells, which demonstrats that the probe is able to detect the endogenous senescence-associated β-galactosidase in living cells.

Targeting senescent cells in translational medicine

“…This probe produces a blue‐to‐yellow emission response to β‐gal and has high insensitivity to pH and reactive oxygen species, high photostability and low cytotoxicity. Gal‐Pro, another senescence‐specific fluorescent probe, was recently validated in vitro using HDFs undergoing oxidative stress‐induced senescence (Zhang et al , ). Gal‐Pro is based on a hemicyanine skeleton conjugated with a D ‐galactose residue via a glycosidic bond displaying near‐infrared emission.…”

In Situ Generated Novel 1H MRI Reporter for β-Galactosidase Activity Detection and Visualization in Living Tumor Cells

“…Thus, β-gal activity detection has been exploited with diverse techniques including colorimetric assays (James et al, 2000;Browne et al, 2010;Zeng et al, 2012;Yeung et al, 2013;Chen et al, 2016; Abbreviations: NMR, nuclear magnetic resonance; MRS, magnetic resonance spectroscopy; MRI, magnetic resonance imaging; TR, repetition time; TE, echo time; β-gal, β-galactosidase; FAC, ferric ammonium citrate, TBAB, tetrabutylammonium bromide; CH2Cl2, dichloromethane; HRMS, high-resolution mass spectrometry; PBS, phosphate-buffered saline; X-Gal, 5bromo-4-chloro-3-indolyl-β-D-galactopyranoside; S-Gal, 3,4-cyclohexenoesculetin β-D-galactopyranoside; DMSO, dimethyl sulfoxide; TLC, thin-layer chromatography. 2017), fluorescence (Tung et al, 2004;Urano et al, 2005;Josserand et al, 2007;Kamiya et al, 2007;Feng et al, 2009;Koide et al, 2009;Kamiya et al, 2011;Oushiki et al, 2012;Han et al, 2013;Sakabe et al, 2013;Lee et al, 2014;Asanuma et al, 2015;Peng et al, 2015;Zeng et al, 2015;Doura et al, 2016;Gu et al, 2016;Zhang C. et al, 2016;Zhang X. X. et al, 2016;Jiang et al, 2017;Kim et al, 2017;Nakamura et al, 2017;Wei et al, 2017;Zhang et al, 2017;Tang et al, 2017;Chen et al, 2018;Ito et al, 2018;Liu et al, 2018;Yang et al, 2018;Chen et al, 2019;Fu et al, 2019;Gu et al, 2019;…”

A ratiometric fluorescent probe for the detection of β-galactosidase and its application

“…To this end, the development of novel uorescent probes is very promising, [24][25][26][27][28][29] and many kinds of b-gal probes have been reported for use in biological imaging, [30][31][32] including two-photon uorescence probes, 33,34 ratiometric probes, 35,36 and turn-on probes. [37][38][39] However, uorescent probes used in fruit detection are extremely rare in scientic literature. 40,41 To develop a simple detection method for b-gal activity in fruit, a ratiometric uorescent probe (Probe 1) with high accuracy and detection precision was developed.…”