Affordable Access

Access to the full text

Ratiometric fluorescent immunoassay for the cardiac troponin-I using carbon dots and palladium-iridium nanocubes with peroxidase-mimicking activity

Authors
  • Tan, Xiaofeng1
  • Zhang, Lianhua2
  • Tang, Qiaorong1
  • Zheng, Gengxiu1
  • Li, He1, 3
  • 1 University of Jinan, School of Chemistry and Chemical Engineering, and Institute of Surface Analysis and Chemical Biology, Jinan, 250022, China , Jinan (China)
  • 2 Shanghai Jiao Tong University School of Medicine, Renji Hospital, Shanghai, 200127, China , Shanghai (China)
  • 3 Chengdu University of Information Technology, College of Optoelectronics Technology, Chengdu, 610225, China , Chengdu (China)
Type
Published Article
Journal
Microchimica Acta
Publisher
Springer-Verlag
Publication Date
Apr 13, 2019
Volume
186
Issue
5
Identifiers
DOI: 10.1007/s00604-019-3375-z
Source
Springer Nature
Keywords
License
Yellow

Abstract

A nanozyme-linked immunosorbent assay is described for cardiac troponin I which is a biomarker for myocardial infarction. The method is based on the use of Pd-Ir nanocubes with excellent peroxidase-like activity. The nanocubes catalyze the oxidization of nonfluorescent o-phenylenediamine (OPD) by H2O2 to form a yellow fluorescent product (oxOPD) with excitation/emission maxima at 400/570 nm. Carbon dots are added as a reference fluorophore. Under the same excitation wavelength, they display blue fluorescence (450 nm). The ELISA uses the Pd-Ir nanocubes as a label for the secondary antibody and OPD as substrate. The ratio of fluorescence intensities at 570 and 450 nm increases in the 1 pg·mL−1 to 1 ng·mL−1 cardiac troponin I concentration range, and the detection limit is 0.31 pg·mL−1. The method was applied to analyze spiked serum samples, and the results compared well with those obtained by a commercial chemiluminescence assay. Graphical abstractSchematic presentation of the ratiometric fluorescence immunoassay for cardiac troponin-I. Pd-Ir nanocubes were employed to fabricate nanozyme-based signal labels for its excellent peroxidase-mimicking activity.

Report this publication

Statistics

Seen <100 times