An electrochemiluminescence biosensor based on boron nitride quantum dots as novel coreactant for quantitative...

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 AP^2-*, 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).