A fluorescent light-up probe based on AIE and ESIPT processes for β-galactosidase activity detection and visualization in living cells

Abstract

A fluorescent probe with both AIE and ESIPT characteristics is developed for a β-galactosidase activity study in solution and living cells.

Aggregation‐Induced Emission: Lighting up Cells, Revealing Life!

“…i) Detection of β‐galactosidase activity in living C6/LacZ cells, which express β‐galactosidase, and HeLa cells, which do not. Both cell lines were stained with 50 μM SA‐bGal for 2 h. Reproduced with permission . Copyright 2015, Royal Society of Chemistry.…”

“…The development of a selective and sensitive probe for β‐galactosidase will be beneficial for evaluating gene transfection efficiency. For this purpose, Liu and co‐workers have developed a light‐up AIE probe, SA‐βGal, with excited‐state intramolecular proton transfer (ESIPT) properties, to evaluate β‐galactosidase activity in living cells . The probe possesses two β‐galactopyranoside groups as the β‐galactosidase reaction sites and salicylaldehyde azine (SA) as the fluorophore (Figure h).…”

“…For this purpose, Liu and co-workers have developed a light-up AIE probe, SA-βGal, with excited-state intramolecular proton transfer (ESIPT) properties, to evaluate β-galactosidase activity in living cells. [33] The probe possesses two β-galactopyranoside groups as the β-galactosidase reaction sites and salicylaldehyde azine (SA) as the fluorophore (Figure 3h). It emitted very weak fluorescence in aqueous buffer, whereas it exhibited strong greenish yellow fluorescence in the presence of β-galactosidase.…”

A New Fluorescent Probe Based on Aggregation Induced Emission for Selective and Quantitative Determination of Copper(II) and its Further Application to Cysteine Detection

“…AIE fluorophore systems could be classified to three types: aryl substituted heterocyclic compounds, intramolecular charge transfer compounds, hydrogen‐ bonding compounds. TPESAA are a class of hydrogen‐bonding compounds which are AIE‐active . The hydroxyl groups at the ortho ‐position on the benzene ring of these compounds are key factor for their AIE fluorescence because that intramolecular hydrogen bonds of salicylaldimine moieties and stacking of molecules in aggregate state inhibit the free intramolecular rotation resulting in the reduced attenuation of non‐radioactive energy to trigger the fluorescence “turn on” .…”

A Pyrone‐based Ratiometric Probe for Galactosidase with Dramatic Color and Fluorescence Changes

“…2 Recently, various activatable fluorophores for the enzyme were developed from modified X-Gal, 3 that produced intense fluorescence signals by chemical reaction-based activation. [4][5][6][7][8][9][10][11] However, a few ratiometric fluorescent probes have been developed due to the environmental artifact-free signaling properties. [12][13][14] For example, Zhu group recently published an excellent ratiometric fluorophore for β-Gal from a precursor, benzopyrone.…”