ECL Biosensor for Sensitive Detection of Soybean Agglutinin Based on AuPt@C60 Nanoflowers Enhanced N-(aminobutyl)-N-(ethylisoluminol)

A sandwich electrochemiluminescence (ECL) biosensing system for soybean agglutinin (SBA) detection was developed with AuPt@C60 nanoflowers (AuPt@C60 NFs) as a novel co-reactant accelerator to enhance the performance of N-(aminobutyl)-N-(ethylisoluminol) (ABEI). In this strategy, nanoflower-liked AuPt@C60 complex served as a matrix for loading a large sum of ABEI and galactosamine (Gal) by Au-N and Pt-N bonds to achieve the nanocomposite Gal-ABEI-AuPt@C60 NFs. Dissolved oxygen was used as a co-reaction reagent, while AuPt@C60 complex acted as a co-reactant accelerator for dissolved oxygen to enhanced the ECL emission of ABEI. Gal, as an identifying element, was highly loaded by electrodeposited gold nanoparticles (Dp Au) on the electrode to recognize SBA, and further combine with Gal-ABEI-AuPt@C60 NFs to form a sandwich model. As a result, the proposed SBA biosensor exhibited a wide linear range from 1.0 ng·mL−1 to 5.0 μg·mL−1 and a low detection limit of 0.33 ng·mL−1. In addition, the biosensor displayed an excellent selectivity and an acceptable stability and reproducibility. The combination of AuPt@C60 NFs and ABEI provided a new ECL sensing platform without exogenous co-reactant.