title: Rapid and cost-effective detection of sequence-specific DNA by monitoring the electrochemical response of 2'-deoxyguanosine 5'-triphosphate in a PCR sample.
abstract: This study describes a novel strategy for rapid and cost-effective detection of sequence-specific DNA based upon the essential utility of the polymerase chain reaction (PCR) and electrochemical technologies. A dramatic enhancement of the anodic peak current (i(pa)) and a visible decrease of overpotential towards free 2'-deoxyguanosine 5'-triphosphate (dGTP) could be realized on a glassy carbon electrode modified with short single-walled carbon nanotubes (S-SWNT/GCE). Thereby, the concentration of the free dGTP in the PCR sample mixture could be determined sensitively. The i(pa) of the free dGTP decreased remarkably after a successful PCR amplification owing to the participation of the free dGTP as one of the reactive substrates for the PCR products, namely dsDNA. Based upon this response change of the free dGTP before and after incorporation in PCR, a novel method aiming at detecting PCR results was established. One transgenic maize sample as a model was successfully detected by employing the specific sequences of 35S promoter from cauliflower mosaic virus (CaMV35S) gene and nopaline synthase (NOS) gene as markers. The result was in good accordance with that obtained with gel electrophoresis.
authors.affiliation: Key Laboratory of Eco-Chemical Engineering of Ministry of Education, College of Chemistry & Molecular Engineering, Qingdao University of Science & Technology, Qingdao, PR China.
authors.forename: Xuzhi
authors.initials: X
authors.lastname: Zhang
authors.forename: Shufeng
authors.initials: S
authors.lastname: Liu
authors.forename: Kui
authors.initials: K
authors.lastname: Jiao
authors.forename: Hongwei
authors.initials: H
authors.lastname: Gao
authors.forename: Yanjing
authors.initials: Y
authors.lastname: Shi
mesh_terms: D000594:Amino Acid Oxidoreductases / Q000235:genetics; D000818:Animals; D017796:Caulimovirus / Q000235:genetics; D003362:Cost-Benefit Analysis; D004247:DNA / Q000032:analysis*; D004279:DNA, Viral / Q000032:analysis; D003848:Deoxyguanine Nucleotides / Q000737:chemistry; D004563:Electrochemistry / Q000379:methods; D037742:Nanotubes, Carbon; D016133:Polymerase Chain Reaction / Q000191:economics / Q000379:methods
chemical_list: D004279:DNA, Viral; D003848:Deoxyguanine Nucleotides; D037742:Nanotubes, Carbon; C029603:deoxyguanosine triphosphate; D004247:DNA; D000594:Amino Acid Oxidoreductases; C021883:nopaline synthase