The electrochemiluminescence coreactant accelerator of metal–organic frameworks grafted with N-(aminobutyl)-N-(ethylisoluminol) for the ultrasensitive detection of chloramphenicol

Abstract

In this work, metal–organic frameworks (MOFs) are utilized as effective ECL coreactant accelerator to enhance the ECL responses of N-(aminobutyl)-N-(ethylisoluminol) (ABEI). Zn-based MOFs (MOF-Zn-1) were prepared by chelating Zn ions with melamine and thiophenedicarboxylic acid (TPDA), which observably accelerated the electrocatalytic oxidation of tripropylamine (TPA). Then, ABEI-MOF-Zn-1 as a high-performance ECL emitter was synthesized via an amide reaction between ABEI and mercaptopropionic acid (MPA) modified MOF-Zn-1. Strikingly, the ABEI-MOF-Zn-1 showed the 18-fold increase in the ECL signals relative to pure ABEI by using TPA as a coreactant. Moreover, ferrocene (Fc) as a quencher was first linked with capture DNA (cDNA), and then used to modify the ABEI-MOF-Zn-1, thereby constructing a label-free ECL biosensor. After the linkage between chloramphenicol (CAP) and aptamer DNA (aptDNA), the ECL response was definitely recovered by releasing L-DNA from double-stranded DNA (dsDNA, hybridization of aptDNA and L-DNA). The resultant sensor showed a wide linear range of 1.00 nM–0.10 mM (R² = 0.99) and a low limit of detection (LOD) down to 0.11 nM for detecting CAP. This work developed a novel pattern to design an efficient ECL enhanced emitter, coupled by expanding its potential applications in clinical diagnosis.