title: Electrochemical evaluation of DNA methylation level based on the stoichiometric relationship between purine and pyrimidine bases.
abstract: An efficient electrochemical approach for the evaluation of DNA methylation level was proposed according to the oxidation signal of DNA bases at an overoxidized polypyrrole (PPyox) directed multiwalled carbon nanotubes (MWNTs) film modified glassy carbon electrode (GCE). The PPyox/MWNTs/GCE exhibited remarkable electrocatalytic activities towards the oxidation of DNA bases due to the advantages of wide potential window, large effective surface area, and excellent antifouling property. As a result, all purine and pyrimidine bases of guanine (G), adenine (A), thymine (T), cytosine (C) and 5-methylcytosine (5-mC) exhibited well identified oxidation peaks at the PPyox/MWNTs/GCE. The direct potential resolution between 5-mC and C was obtained to be 180 mV, which was large enough for their signal recognition and accurate detection in mixture. In particular, the signal interference from T, a great challenge in exploring DNA methylation, was successfully eliminated by an innovative strategy, which was developed based on the stoichiometric relationship between purine and pyrimidine bases in DNA molecular structure. The proposed method was effectively applied to the rapid detection of DNA methylation status in real sample within 45 min with satisfactory results.
authors: Jiangsu Key Laboratory of Green Synthetic Chemistry for Functional Materials, School of Chemistry and Chemical Engineering, Jiangsu Normal University, Xuzhou 221116, PR China. wangpo@jsnu.edu.cn
authors: Po
authors: P
authors: Wang
authors: Hanbin
authors: H
authors: Chen
authors: Jiuying
authors: J
authors: Tian
authors: Zong
authors: Z
authors: Dai
authors: Xiaoyong
authors: X
authors: Zou
mesh_terms: D015374:Biosensing Techniques / Q000379:methods*; D004247:DNA / Q000737:chemistry / Q000302:isolation & purification*; D019175:DNA Methylation; D055664:Electrochemical Techniques; D006801:Humans; D037742:Nanotubes, Carbon / Q000737:chemistry; D010084:Oxidation-Reduction; D011687:Purines / Q000302:isolation & purification*; D011743:Pyrimidines / Q000302:isolation & purification*
chemical_list: D037742:Nanotubes, Carbon; D011687:Purines; D011743:Pyrimidines; D004247:DNA; C030986:pyrimidine; C030985:purine