Jump to main content
Jump to site search

Issue 9, 2018
Previous Article Next Article

Electrochemical signal-amplified detection of 5-methylcytosine and 5-hydroxymethylcytosine in DNA using glucose modification coupled with restriction endonucleases

Author affiliations

Abstract

The levels of 5-methylcytosine (5-mC) and 5-hydroxymethylcytosine (5-hmC) in DNA (5-mC-DNA and 5-hmC-DNA) are strongly correlated with cancer occurrence and development. The ability to distinguish and quantitatively detect them is important for cancer research. We have developed a hybridization chain reaction (HCR)-based electrochemical assay for the signal-amplified detection of the relative contents of 5-mC-DNA and 5-hmC-DNA. The DNA duplexes (containing 5-mC-DNA and 5-hmC-DNA with different percentages) were modified on a gold electrode. Electroactive [Ru(NH3)6]3+ (RuHex) was used as the signal reporter, because it binds to DNA double strands. The duplexes can be cleaved by MspJI endonuclease without HCR, and result in a small peak current. However, the cleavage can be blocked after the 5-hmC-DNA duplex is converted to β-glucosyl-5-hydroxymethylcytosine (β-glu-5-hmC) by T4 β-glucosyltransferase (T4 β-GT), and with the addition of helper DNA, a long double-helix DNA was formed through HCR. A significantly amplified peak current can be achieved due to the adsorption of numerous RuHex. The electrochemical signal of RuHex is correlated to the content of 5-hmC-DNA. Upon fixing the total quantity of 5-mC-DNA and 5-hmC-DNA on the electrode, the signals increase with the increase in the percentage of 5-hmC-DNA for the HCR. With this assay, a detection limit of 0.05% for 5-hmC-DNA was achieved.

Graphical abstract: Electrochemical signal-amplified detection of 5-methylcytosine and 5-hydroxymethylcytosine in DNA using glucose modification coupled with restriction endonucleases

Back to tab navigation

Supplementary files

Publication details

The article was received on 19 Dec 2017, accepted on 15 Mar 2018 and first published on 16 Mar 2018


Article type: Paper
DOI: 10.1039/C7AN02049J
Citation: Analyst, 2018,143, 2051-2056
  •   Request permissions

    Electrochemical signal-amplified detection of 5-methylcytosine and 5-hydroxymethylcytosine in DNA using glucose modification coupled with restriction endonucleases

    Y. Yang, G. Yang, H. Chen, H. Zhang, J. Feng and C. Cai, Analyst, 2018, 143, 2051
    DOI: 10.1039/C7AN02049J

Search articles by author

Spotlight

Advertisements