Electrochemiluminescence immunoassay of cTnI with ruthenium-based metal covalent organic framework and dual DNAzymes cascade amplification strategy

Sheng-Han Tang; Ling Qin; Wei-Guo Yang; Ruo Yuan; Jun Yang; Yan Li; Shan-Shan Hu

doi:10.1002/chem.202404053

Electrochemiluminescence immunoassay of cTnI with ruthenium-based metal covalent organic framework and dual DNAzymes cascade amplification strategy

Chemistry. 2024 Dec 23:e202404053. doi: 10.1002/chem.202404053. Online ahead of print.

Authors

Sheng-Han Tang¹, Ling Qin¹, Wei-Guo Yang¹, Ruo Yuan¹, Jun Yang¹, Yan Li², Shan-Shan Hu³

Affiliations

¹ Southwest University, college of chemistry and chemical engineering, CHINA.
² Southwest University, analytical and testing center, CHINA.
³ Southwest University, school of chemistry and chemical enjineering, 2 Tiansheng Road, Beibei District, Chongqing, 400700, Chongqing, CHINA.

PMID: 39716272
DOI: 10.1002/chem.202404053

Abstract

Currently, metal-organic frameworks (MOFs) with tunability and covalent organic frameworks (COFs) with high stability are promising nanomaterials for electrochemiluminescence (ECL), while Ru-based metal covalent organic frameworks (Ru-MCOFs) have rarely been reported. Herein, an ECL immunosensor based on a strong ECL-emitting Ru-MCOF was proposed for the sensitive detection of the cardiac troponin-I (cTnI). Imine-linked Ru-MCOF was prepared as an ECL emitter via solvothermal method using tris(4,4' -diamino-2,2' -bipyridine)ruthenium(II) (Ru(dbpy)32+) as a precursor. Compared with monomers, the imine-linked Ru-MCOF achieved structural extension through covalent bonds, which not only effectively facilitated the electrochemical activation of the luminophores but also shortened the transmission distance between electrons and co-reactants, generating dense ECL emission. In addition, the porous framework of Ru-MCOF provided a microreactor with nanoconfinement effect, which could accelerate the diffusion of co-reactants into the framework and promote the excitation of internal and external ECL emitters, significantly enhancing the ECL intensity. Considering the excellent ECL performance of Ru-MCOF, combined with dual DNAzymes-driven catalytic hairpin cycle amplification, the ECL immunosensor achieved sensitive detection of cTnI with a detection limit as low as 0.42 fg/mL. The proposed highly stable Ru-MCOF raises a new approach for exploring MCOF-based luminophores, highlighting the potential of MCOFs in advancing ECL emitters.

Keywords: electrochemiluminescence, Ru-MCOF, DNAzymes, cTnI.