title: Hairpin DNA probe based electrochemical biosensor using methylene blue as hybridization indicator.
abstract: In this paper, a label-free, rapid and simple method was proposed to study the hybridization specificity of hairpin DNA probe using methylene blue (MB) as a hybridization indicator. Thiolated hairpin DNA probe was immobilized on the gold electrode by self-assembly. The voltammetric signals of MB were investigated at these modified electrodes by means of cyclic voltammetry (CV) detection. Single-base mutation oligonucleotide and random oligonucleotide can be easily discriminated from complementary target DNA. The effect of mismatch position in target DNA was investigated. Experimental results showed that mutation in the center of target DNA had greatest effect on the hybridization with hairpin DNA probe. The relationship between electrochemical responses and DNA target concentration was also studied. The reduction current of MB intercalation decreased with increasing the concentration of target DNA. Taken together, these experiments demonstrate that the hybridization indicator MB provides great promise for rapid and specific measurement of target DNA.
authors.affiliation: Department of Chemistry, Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology, Tsinghua University, Beijing 100084, PR China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Jin
authors.forename: Xin
authors.initials: X
authors.lastname: Yao
authors.forename: Qing
authors.initials: Q
authors.lastname: Liu
authors.forename: Jinghong
authors.initials: J
authors.lastname: Li
mesh_terms: D015374:Biosensing Techniques / Q000295:instrumentation / Q000379:methods*; D015342:DNA Probes / Q000737:chemistry* / Q000235:genetics*; D004563:Electrochemistry / Q000295:instrumentation / Q000379:methods*; D017403:In Situ Hybridization / Q000295:instrumentation / Q000379:methods*; D008751:Methylene Blue; D020411:Oligonucleotide Array Sequence Analysis / Q000295:instrumentation / Q000379:methods*
chemical_list: D015342:DNA Probes; D008751:Methylene Blue