Jump to main content
Jump to site search


Ag+-coordinated oligonucleotides on gold nanoparticle for anodic-stripping voltammetric immunoassay of cancer antigen 125 for cervical carcinoma

Abstract

A simple and enzyme-free electrochemicla immunoassay was developed for the sensitive screening of cancer antigen 125 (CA 125; one biomarker for epithelial ovarian tumors and cervical carcinoma) using anodic-stripping voltammetry (ASV). The electrochemical immunosensor was constructed through immobilization of monocolonal anti-CA 125 antibody on an activated glassy carbon electrode on the basis of a classical carbodiimide coupling method. Cytosine (C)-rich oligonucleotide strands and polyclonal anti-CA 125 antibody labeled onto gold nanoparticle (AuNP) were used as the detection probes to quantify the target analyte with a sandwiched assay format. The voltammetric signal derived from the coordinated silver ion (Ag+) on the AuNP through the C-Ag+-C coordination chemistry. Accompanying the formation of target-induced immunocomplexes, the coordinated Ag+ ions exhibited good voltammetric characteristics within the applied potentials. Under optimal conditions, the C-Ag+-C-based immunoassay displayed the sensitive responses toward target CA 125 within a dynamic linear range of 0.01 – 100 U mL-1 at a limit of detection of 6.8 mU mL-1. Good reproducibility, high specificity and accpetable accuracy of this method were acquired for analysis of human serum specimens. Importantly, this immunoassay system offers a promising protocol for the detection of disease-related biomarkers without the needs of natural enzymes.

Back to tab navigation

Publication details

The article was received on 25 Apr 2019, accepted on 15 May 2019 and first published on 15 May 2019


Article type: Paper
DOI: 10.1039/C9AY00875F
Anal. Methods, 2019, Accepted Manuscript

  •   Request permissions

    Ag+-coordinated oligonucleotides on gold nanoparticle for anodic-stripping voltammetric immunoassay of cancer antigen 125 for cervical carcinoma

    H. Xue, J. Zheng, Q. Chen, Q. Wang, Y. Lin and J. Chen, Anal. Methods, 2019, Accepted Manuscript , DOI: 10.1039/C9AY00875F

Search articles by author

Spotlight

Advertisements