Potential-resolved differential electrochemiluminescence immunosensor based on novel designed IBPHF for self-correctable detection of AFB1

Abstract

Electrochemiluminophore system with potential-resolved has exhibited giant potentiality for the application of bioassays in recent years, however, rarely studies toward the novel luminophore with potential-resolved electrochemiluminescence (PRECL) have been reported. In this work, a novel organoboron complex microrod (IBPHF) with PRECL property was synthesized, which emitted two strongest electrochemiluminescence (ECL) signals in the anode region at around 1.5 V and cathode region at around −1.5 V by using tri-n-propylamine (TPA)/K2S2O8 as coreactant. The relevant ECL properties and luminescence mechanisms have been discussed in detail. Moreover, electroactive substrate of three-dimensional porous starch carbon nanomaterials (3D-PSC NPs) were designed to capture antibodies. As a result, the competitive potential-resolved differential electrochemiluminescence immunosensor was fabricated, and greatly enhanced sensitivity was achieved by using IBPHF by using IBPHF as a carrier to label competing antigens. In the presence of aflatoxin B1 (AFB1), due to the competitive mechanism and the specific recognition of antigen–antibody, the well-prepared immunosensor performed a quantitative decreasement in the range from 50 fg/mL to 100 ng/mL with a minimum detectable limit of 16.44 fg/mL by using the intensity difference (△ECL) (ECLanode-ECLcathode). The self-correction of △ECL extremely enhanced the accuracy and reliability of the sensor. Furthermore, the designed sensor achieved excellent detection towards AFB1 in walnut samples, and performed a bright application for trace target detection in future.