An electrochemiluminescence biosensor based on boron nitride quantum dots as novel coreactant for quantitative determination of concanavalin A.

An electrochemiluminescence (ECL) analytical platform is constructed based on boron nitride quantum dots (BNQDs) as a novel coreactant of luminol for quantitative assay of concanavalin A (Con A). Different from previous research that mainly focuses on its superior optical properties, BNQDs are used for the first time as a coreactant for boosting ECL intensity of luminol, which has a 10-fold enhancement compared with individual poly(luminol/aniline) nanorods loaded on reduced graphene oxide (PLA-rGO) using GCE. On the basis that BNQDs contain an abundance of active amino, a possible mechanism of amino oxidation facilitating ECL emission is proposed. Firstly, luminol as light spices are oxidized to luminol•- and BNQDs generate an abundance of BNQDs-NH+• via electrochemical oxidization, producing reductive intermediates BNQDs-N• in alkaline conditions. Finally, BNQDs-N• react with luminol•- to obtain the excited species AP2-*, returning to ground state and emitting light. Due to the hindrance effect of Con A, the ECL intensity decreases gradually as various concentrations of Con A are modifying the electrode surface. Therefore, a sensitive ECL biosensor for detecting Con A is constructed exhibiting a wide linear range of 1.0 pg·mL-1 to 1.0 μg·mL-1 and a low detection limit of 0.15 pg·mL-1. Graphical abstract Schematic representation of an electrochemiluminescence (ECL) biosensor based on boron nitride quantum dots (BNQDs) as an efficient coreactant of reduced graphene oxide functionalized poly(luminol/aniline) (PLA-rGO) for quantitative assay of concanavalin A (Con A).