title: Development of an electrochemical sensor based on the catalysis of ferrocene actuated hemin/G-quadruplex enzyme for the detection of potassium ions.
abstract: Sensitive and selective sensors need to be explored to detect the physiological potassium level due to its important role in the living organisms. In the present system, a novel electron transfer mediator actuated electrocatalytical biosensor was demonstrated to assay K(+) based on the conformational change of DNA. With the hybridization between the complementary bases and the self-folding of guanine-rich nucleic acid sequence, the horseradish peroxidase-mimicking enzyme (HRP-DNAzyme) was formed and brought to approach the ferrocene (Fc) unit on Au nanoparticles (AuNPs). Thus, in the system, Fc unit acted as the relay, stimulating the electrical contact of HRP-DNAzyme with the electrode to obtain the bioelectrocatalyze reduction signal. Under the Fc actuated catalysis of HRP-DNAzyme and amplification of Au nanoparticles, the obtained biosensor exhibited a sensitive detection for K(+). A satisfying result of a wide linear range and low detection limit were obtained with the novel electrocatalytical biosensor which was then applied in real samples.
authors.affiliation: Key Laboratory of Chem-Biosensing, Anhui Province; Key Laboratory of Functional Molecular Solids, Anhui Province; College of Chemistry and Materials Science, Center for Nano Science and Technology, Anhui Normal University, Wuhu 241000, PR China; State Key Laboratory of Chemo/Biosensing and Chemometrics, Hunan University, Changsha 410082, PR China. Electronic address: wangyuz@mail.ahnu.edu.cn.
authors.forename: Guangfeng
authors.initials: G
authors.lastname: Wang
authors.affiliation: Key Laboratory of Chem-Biosensing, Anhui Province; Key Laboratory of Functional Molecular Solids, Anhui Province; College of Chemistry and Materials Science, Center for Nano Science and Technology, Anhui Normal University, Wuhu 241000, PR China; State Key Laboratory of Chemo/Biosensing and Chemometrics, Hunan University, Changsha 410082, PR China.
authors.forename: Ling
authors.initials: L
authors.lastname: Chen
authors.affiliation: Key Laboratory of Chem-Biosensing, Anhui Province; Key Laboratory of Functional Molecular Solids, Anhui Province; College of Chemistry and Materials Science, Center for Nano Science and Technology, Anhui Normal University, Wuhu 241000, PR China; State Key Laboratory of Chemo/Biosensing and Chemometrics, Hunan University, Changsha 410082, PR China.
authors.forename: Yanhong
authors.initials: Y
authors.lastname: Zhu
authors.affiliation: Key Laboratory of Chem-Biosensing, Anhui Province; Key Laboratory of Functional Molecular Solids, Anhui Province; College of Chemistry and Materials Science, Center for Nano Science and Technology, Anhui Normal University, Wuhu 241000, PR China; State Key Laboratory of Chemo/Biosensing and Chemometrics, Hunan University, Changsha 410082, PR China.
authors.forename: Xiuping
authors.initials: X
authors.lastname: He
authors.affiliation: Key Laboratory of Chem-Biosensing, Anhui Province; Key Laboratory of Functional Molecular Solids, Anhui Province; College of Chemistry and Materials Science, Center for Nano Science and Technology, Anhui Normal University, Wuhu 241000, PR China; State Key Laboratory of Chemo/Biosensing and Chemometrics, Hunan University, Changsha 410082, PR China.
authors.forename: Gang
authors.initials: G
authors.lastname: Xu
authors.affiliation: Key Laboratory of Chem-Biosensing, Anhui Province; Key Laboratory of Functional Molecular Solids, Anhui Province; College of Chemistry and Materials Science, Center for Nano Science and Technology, Anhui Normal University, Wuhu 241000, PR China; State Key Laboratory of Chemo/Biosensing and Chemometrics, Hunan University, Changsha 410082, PR China. Electronic address: xjzhang@mail.ahnu.edu.cn.
authors.forename: Xiaojun
authors.initials: X
authors.lastname: Zhang
mesh_terms: D015374:Biosensing Techniques / Q000295:instrumentation*; D021881:DNA, Catalytic / Q000737:chemistry; D058266:Dielectric Spectroscopy; D055664:Electrochemical Techniques / Q000295:instrumentation; D004867:Equipment Design; D005296:Ferrous Compounds / Q000737:chemistry*; D054856:G-Quadruplexes; D006046:Gold / Q000737:chemistry*; D006427:Hemin / Q000737:chemistry*; D006735:Horseradish Peroxidase / Q000737:chemistry; D053768:Metal Nanoparticles / Q000737:chemistry*; D000075163:Metallocenes; D011188:Potassium / Q000032:analysis*
chemical_list: D021881:DNA, Catalytic; D005296:Ferrous Compounds; D000075163:Metallocenes; D006427:Hemin; D006046:Gold; D006735:Horseradish Peroxidase; D011188:Potassium; C004998:ferrocene
keywords: Au nanoparticles; Bioelectrocatalysis; Hemin/G-quadruplexes; Horseradish peroxidase-mimicking enzyme; Potassium ions