A fluorescent turn on/off probe for glucose detection based on a boronic acid-capped 1,1′-ferrocenedicarboxylic acid functional graphene oxide

Abstract

The accurate determination of glucose in the human body is highly desired because excessive ingestion of glucose may lead to obesity, diabetes and other diseases. This work demonstrates a fluorescent probe for sugar detection using the unique affinity of boronates for cis -diols. The fluorescent sensing system is composed of two components: 1) Aminated graphene oxide (GON) decorated with phenylboronic acid (BPA) and 1,1'-ferrocenedicarboxylic acid (FCA) as a fluorescence quencher (FCA–GON–BPA); and 2) fluorophores of a cis -diol modified tetraphenylethylene derivative (TPBD) with aggregation-induced emission (AIE) characteristics as the luminescence. FCA–GON–BPA can selectively bind cis -diol-containing fluorogens, such as TPBD, resulting in fluorescence quenching of the probe system. Upon addition of glucose, a new cyclic boronate ester is formed, resulting in the cis -diol-containing fluorogen dissociating from the quenched system, and TPBD fluorescence is recovered. The probe has an obvious response to the presence of glucose and a low limit of detection (LOD, 4.36 mg/mL). • The fluorophore has the characteristics of aggregation-induced emission. • The reaction platform is graphene oxide with high adsorption surface area. • Glucose preempts binding of fluorophore and quencher to release fluorescence.