title: Label-free and amplified electrochemical detection of cytokine based on hairpin aptamer and catalytic DNAzyme.
abstract: In this work, by incorporating a specific DNAzyme sequence into a hairpin aptamer probe, we describe a label-free and sensitive method for electrochemical detection of cytokines using recombinant human IFN-γ as the model analyte. The hairpin aptamer probes are immobilized on a gold electrode through self-assembly. The presence of IFN-γ opens the hairpin structure and forms the hemin/G-quadruplex peroxidase-mimicking DNAzyme with subsequent addition of hemin. The peroxidase-mimicking DNAzyme catalyzes the electro-reduction of H(2)O(2) and amplifies the current response for IFN-γ detection, which enables the monitoring of IFN-γ at the sub-nanomolar level. The proposed sensor also shows high selectivity towards the target analyte. Our strategy thus opens new opportunities for label-free and amplified detection of different types of cytokines.
authors.affiliation: Key Laboratory on Luminescence and Real-Time Analysis, Ministry of Education, School of Chemistry and Chemical Engineering, Southwest University, Chongqing, 400715, PR China.
authors.forename: Haixia
authors.initials: H
authors.lastname: Zhang
authors.forename: Bingying
authors.initials: B
authors.lastname: Jiang
authors.forename: Yun
authors.initials: Y
authors.lastname: Xiang
authors.forename: Yaqin
authors.initials: Y
authors.lastname: Chai
authors.forename: Ruo
authors.initials: R
authors.lastname: Yuan
mesh_terms: D052157:Aptamers, Nucleotide / Q000737:chemistry; D015374:Biosensing Techniques / Q000379:methods*; D021881:DNA, Catalytic / Q000737:chemistry* / Q000378:metabolism; D055664:Electrochemical Techniques / Q000379:methods*; D054856:G-Quadruplexes; D006427:Hemin / Q000737:chemistry; D006801:Humans; D007371:Interferon-gamma / Q000032:analysis* / Q000737:chemistry; D055029:Inverted Repeat Sequences; D013194:Staining and Labeling
chemical_list: D052157:Aptamers, Nucleotide; D021881:DNA, Catalytic; D006427:Hemin; D007371:Interferon-gamma