An Electrochemiluminescent Biosensor Based on Interactions between a Graphene Quantum Dot−Sulfite Co‐reactant System and Hydrogen Peroxide

Abstract

Dedicated to Professor Qinjin Wan on the occasion of his 60th birthdayGraphene quantum dots (GQDs) are recently emerging carbon nanomaterials. GQDs have been recognized as attractive electrochemiluminescence (ECL) luminophores, owing to their environmental friendliness, facile preparation, easy labeling, and high ECL activity. However, in terms of the co-reactant of GQDs ECL, only strongly oxidative S 2 O 8 2À has been well studied and applied in GQD-based ECL sensing, which seriously limits the application of GQD ECL sensors. In the present work, we found that the commonly used reducing reagent, sulfite (SO 3 2À ), could serve as a new type of co-reactant of GQD ECL. Moreover, GQDs exhibited much higher ECL activity than spherical carbon quantum dots when using SO 3 2À as the co-reactant, owing to more abundant surface states of GQDs. Further investigation showed that GQD/SO 3 2À ECL could be sensitively quenched by H 2 O 2 at physiological pH. On this basis, new, green, and simple ECL chemical and biological sensors have been proposed for the detection of H 2 O 2 and biologically interesting molecules such as glucose. Additionally, the ECL reaction and sensing mechanisms have also been studied and discussed.

Au decorated core-shell structured Au@Pt for the glucose oxidation reaction

“…In particular, it is essential to monitor the patient's glucose level in a timely manner using a robust portable sensor device. To detect glucose, various techniques have been reported, such as chemiluminescence [14], electrochemiluminescence [15], and electrochemical sensors [16]. Among them, electrochemical sensor devices are currently the A C C E P T E D M A N U S C R I P T best choice.…”

Electrochemiluminescence of Carbon‐based Quantum Dots: Synthesis, Mechanism and Application in Heavy Metal Ions Detection

“…Therefore, it is necessary to explore other, newer co‐reactants of CQDs in order to further reveal the ECL mechanism of CQDs and expand its application. In recent years, it has been found that sulfite (SO 3 2− ), hydrogen peroxide (H 2 O 2 ) and L‐cysteine can be used as co‐reactants of CQDs to enhance the ECL cathode emission [61–63]. In addition, Long et al.…”

One-Step Preparation of Nitrogen-Doped Graphene Quantum Dots With Anodic Electrochemiluminescence for Sensitive Detection of Hydrogen Peroxide and Glucose

“…In addition, the structure and performance of GQDs can be easily adjusted by changing the precursor, dopant, or modifier in the “bottom-up” method. However, the current method to produce GQDs with the ECL property mainly uses the “top-down” strategy ( Zhang et al, 2015 ; Chen et al, 2016 ; Zhou et al, 2017 ; Jie et al, 2019 ). These methods usually require complex and harsh synthesis procedures.…”