Jump to main content
Jump to site search


Reduced graphene oxide-gold nanoparticles-catalase-based dual signal amplification strategy in spatial-resolved ratiometric electrochemiluminescence immunoassay

Abstract

A novel spatial-resolved electrochemiluminescent (ECL) ratiometry for cardiac troponin I (cTnI) analysis was developed using resonance energy transfer (RET) and coreactant consumption strategy for signal amplification. Specifically, the spatial-resolved dual-disk glassy carbon electrodes were modified with CdS nanowires (CdS NWs) and luminol-gold nanoparticles (L-Au NPs) as potential-resolved ECL emitters, respectively. After stepwise immobilization of anti-cTnI, bovine serum albumin on the dual-disk electrodes, the CdS NWs-based electrode with varied concentration cTnI was used to provide working signal, whereas the L-Au NPs-based electrode with fixed amount of cTnI was employed to provide the reference signal. To efficiently amplify the working signal on CdS NWs-based electrode, anti-cTnI-reduced graphene oxide-gold nanoparticles-catalase probe (anti-cTnI-rGO-Au NPs-CAT) was loaded onto the electrode to form a sandwich immunocomplex. The RET from CdS NWs to Au NPs and the coreactant (i.e. H2O2) consumption by CAT generate a great ECL decrease on the CdS NWs-based electrode in the presence of cTnI. The new and sensitive ratiometric detection mode for cTnI was achieved by the ratio values of working signal of CdS NWs-based electrode and reference signal of L-Au NPs-based electrode. The integration of RET and coregent consumption strategy in the designed spatial-resolved ratiometric platform endows the immunosensor with a wide linear range of 5.0 × 10-13 – 1.0 × 10-7 g/mL and a low detection limit of 0.10 pg/mL for cTnI. Furthermore, the method exhibits high accuracy and sensitivity for cTnI determination in human serum samples.

Back to tab navigation

Supplementary files

Publication details

The article was received on 14 Oct 2019, accepted on 06 Nov 2019 and first published on 09 Nov 2019


Article type: Paper
DOI: 10.1039/C9AN02056J
Analyst, 2019, Accepted Manuscript

  •   Request permissions

    Reduced graphene oxide-gold nanoparticles-catalase-based dual signal amplification strategy in spatial-resolved ratiometric electrochemiluminescence immunoassay

    J. Cao, X. Fu, F. Liu, S. Ren and Y. Liu, Analyst, 2019, Accepted Manuscript , DOI: 10.1039/C9AN02056J

Search articles by author

Spotlight

Advertisements