A Long‐Wavelength Fluorescent Probe for Saccharides Based on Boronic‐Acid Receptor

Abstract

A single boronic acid-based fluorescent probe (compound CSP) for saccharides was designed and synthesized. The probe, with an α,β-unsaturated ketone conjugated into the coumarin fluorophore, was synthesized by 4 steps from the commercial material 4-diethylamino salicylaldehyde. The electron push-pull effect is enhanced with the N,N-diethyl amino as the electron donor and the carbonyl as the electron acceptor. Both the absorption (463 nm) and emission (616 nm) maxima of CSP are in the visible wavelength region with a Stokes shift of about 150 nm, which ensures CSP a potential probe for biological application. Under near physiological conditions, significant fluorescence enhancement of CSP was observed upon the addition of some saccharides, namely, D-sorbitol, D-fructose, D-glucose, D-mannose and D-galactose. The probe showed relatively high sensitivity towards D-fructose and D-sorbitol, and their detection limits were 0.05 mmol/L and 0.1 mmol/L, respectively.

Boronic acids for sensing and other applications - a mini-review of papers published in 2013

“…Many fluorogenic units are used for reporting the interactions of diols with boronic acids. The fluorophores used include pyrene [ 15 , 16 , 19 ], coumarin [ 21 ], naphthalene [ 22 ] and BODIPY [ 23 ]. Furthermore multi-colorimetric sensor arrays were developed using boronic acid-containing thin films combined with three anionic dyes for saccharide detection.…”

Carbohydrate Sensing Using Water-Soluble Poly(methacrylic acid)-co-3-(Acrylamido)phenylboronic Acid Copolymer

“…The quest for stable artificial receptors with high affinities has been very active in sensing science in the past decades, with particular emphasis on supramolecular analytical contributions. − Understanding the supramolecular interactions most suited to the analyte of interest is fundamental to design effective receptors and generate recognition systems. There has long been great interest in the interaction between boronic acids and molecules containing vicinal cis -diols. − In fact, boronic acids are known to covalently and reversibly bind to cis -diol functional groups, spurring their use to recognize diol-containing compounds such as small sugar molecules and glycoproteins. − …”