Dual-Amplifying Electrochemiluminescence Sensor Based on CdS QDs@HKUST-1/MWCNTs Composite for Sensitive Catechol Assay

Herein, a novel electrochemiluminescence (ECL) sensor was developed using a dual signal amplification mechanism based on a typical HKUST-1 metal-organic framework, [Cu-3(BTC)(2)(H2O)(3), BTC=1,3,5-benzene tricarboxylate], CdS quantum dots (QDs) and multi-walled carbon nanotubes (MWCNTs) for ultrasensitive determination of catechol. HKUST-1 not only has a dispersion effect to carry more CdS QDs for enhancing stability, but also acts as effective catalyzer to accelerate the transformation of persulfate ion (S2O82-) for generating more sulfate radical anions (SO4 center dot-), - therefore amplifying the signal of the ECL sensor. Meanwhile, the introduction of MWCNTs to the ECL process could promote the electron transfer rate and accelerate the kinetics of the electro-catalytic reaction attributing to its stronger conductivity, achieving dual-amplifying effect, which could obviously increase the sensitivity of the ECL sensor. The proposed sensor displayed a wide linear range of 1 x 10(-7) - 1 x 10(-3) M and a low detection limit of 3.8 x 10(-8) M with excellent stability, high repeatability and outstanding anti-interference ability under the optimal conditions. Impressively, the sensor possessed commendable feedback when detecting catechol in real samples. Therefore, this research provided a new strategy combining the advantages of MOFs, QDs and MWCNTs materials for phenolic pollutants detection. (C) 2022 The Electrochemical Society (ECS). Published on behalf of ECS by IOP Publishing Limited.

Automated summary

In this study, a novel electrochemiluminescence (ECL) sensor was developed using a dual signal amplification mechanism with HKUST-1, CdS quantum dots (QDs), and multi-walled carbon nanotubes (MWCNTs) for ultrasensitive detection of catechol. The sensor exhibited a wide linear range, low detection limit, excellent stability, and high anti-interference ability.