title: Construction of Metal-Ion-Free G-quadruplex-Hemin DNAzyme and Its Application in S1 Nuclease Detection.
abstract: In this work, a new kind of peroxidase-mimicking DNAzyme (G-quadruplex-hemin DNAzyme, G4-hemin) was constructed by using hemin-modified G-rich DNA (hemin-G-DNA). Experimental results demonstrated that the G-rich DNA can form a G-quadruplex structure by the inducement of terminally modified hemin, rendering the assembly of hemin and G-quadruplex structure spontaneously and efficiently. As a result, G-hemin revealed higher peroxidase activity than traditional G-quadruplex/hemin DNAzyme (G4/hemin). Besides, different from G4/hemin, G4-hemin was constructed in one step without the participation of metal ions and adscititious hemin. Accordingly, the construction procedure was significantly simplified and the background signal from dissociative hemin was remarkably reduced. In a proof-of-concept trial, according to the colorimetric signals of G4-hemin, a novel biosensor for the detection of S1 nuclease activity was established, which provides a novel perspective for designing peroxidase-mimicking DNAzyme-based biosensors.
authors.affiliation: Jiangsu Key Laboratory of Biofunctional Materials, College of Chemistry and Materials Science, Nanjing Normal University , Nanjing 210023, P. R. China.
authors.forename: Zhaoyin
authors.initials: Z
authors.lastname: Wang
authors.affiliation: Jiangsu Key Laboratory of Biofunctional Materials, College of Chemistry and Materials Science, Nanjing Normal University , Nanjing 210023, P. R. China.
authors.forename: Jian
authors.initials: J
authors.lastname: Zhao
authors.affiliation: Jiangsu Key Laboratory of Biofunctional Materials, College of Chemistry and Materials Science, Nanjing Normal University , Nanjing 210023, P. R. China.
authors.forename: Jianchun
authors.initials: J
authors.lastname: Bao
authors.affiliation: Jiangsu Key Laboratory of Biofunctional Materials, College of Chemistry and Materials Science, Nanjing Normal University , Nanjing 210023, P. R. China.
authors.forename: Zhihui
authors.initials: Z
authors.lastname: Dai
mesh_terms: D000818:Animals; D002417:Cattle; D021881:DNA, Catalytic / Q000138:chemical synthesis*; D003851:Deoxyribonucleases / Q000032:analysis*; D054856:G-Quadruplexes; D006427:Hemin / Q000138:chemical synthesis*; D007477:Ions; D008670:Metals / Q000737:chemistry*; D009195:Peroxidase; D011188:Potassium; D013056:Spectrophotometry, Ultraviolet; D013997:Time Factors
chemical_list: D021881:DNA, Catalytic; D007477:Ions; D008670:Metals; D006427:Hemin; D009195:Peroxidase; D003851:Deoxyribonucleases; D011188:Potassium
keywords: S1 nuclease; colorimetric biosensor; hemin-modified DNA; metal ion-free; peroxidase-mimicking DNAzyme