Ultrasensitive Immunosensor for Cardiac Troponin I Detection Based on the Electrochemiluminescence of 2D Ru-MOF Nanosheets

Abstract

Electrochemiluminescence (ECL)-functionalized metal–organic frameworks (MOFs) have attracted increasing attention in biosensing in virtue of their diverse and tunable optical properties. A famous ECL luminophore, carboxyl-rich tris­(4,4′-dicarboxylic acid-2,2′-bipyridyl) ruthenium­(II) (Ru­(dcbpy)3 2+), possesses the characteristics of good water solubility and excellent ECL performance and also has the potential to be the organic ligand of metal–organic frameworks. Herein, functionalized MOF nanosheets (RuMOFNSs) containing plenty of Ru­(dcbpy)3 2+ in the frameworks were synthesized in aqueous solution by a simple one-pot method. In this protocol, Ru­(dcbpy)3 2+ acted as organic ligand to coordinate with Zn2+ originated from Zn­(NO3)2, and polyvinylpyrrolidone (PVP) was used as structure-directing agent to control the formation of sheetlike structure. For practical application, a “signal-on” ECL immunosensor was designed for cardiac troponin I (cTnI) detection by employing RuMOFNSs as ECL probe. The immunosensor exhibited high sensitivity and excellent selectivity for cTnI detection in the range from 1 fg/mL to 10 ng/mL with a detection limit as low as 0.48 fg/mL. Finally, the biosensor was successfully applied for the detection of cTnI in human serum sample with satisfactory results, demonstrating its potential application in bioanalysis and clinical diagnosis.

“On the Detection of cTnI - A Comparison of Surface-Plasmon Optical -, Electrochemical -, and Electronic Sensing Concepts”

“…The simple question: what is the molecular mechanism and/or a theoretical model by which one could understand that the sensor response changes by a factor of 3-5 (!) upon varying the cTnI concentration by 5-7 orders of magnitude [28][29][30][31][32] (Calling this "linear" is another story…). All reports refer to a bimolecular reaction between the ligand, cTnI, and its antibody or specific aptamer.…”

The TDs/aptamer cTnI biosensors based on HCR and Au/Ti3C2-MXene amplification for screening serious patient in COVID-19 pandemic

“…Until now, lots of researches focused on cTnI detection using immunosensors ( Dong et al, 2020 ; Palanisamy et al, 2020 ; Yan et al, 2019 ; Yang et al, 2018 ; Ye et al, 2019 ; Zhu et al, 2019b ), including electrochemiluminescent (ECL) ones and electrochemical (EC) ones with high selectivity and sensitivity ( Dong et al, 2020 ; Jin et al, 2018 ; Labib et al, 2016 ; Li, Y.Y. et al, 2018; Yang et al, 2018 ).…”

A Novel Graphene-Based Nanomaterial Modified Electrochemical Sensor for the Detection of Cardiac Troponin I

“…The composite of other nanomaterials in rGO can reduce the layer-layer interaction force, so the performance of rGO can be further ensured (Fathil et al, 2017;Lopa et al, 2019). Among them, silver nanomaterial materials are often used in the design of electrochemical sensors due to their cheap price and good electrocatalytic properties (Zhou et al, 2018;Yan et al, 2019).…”