title: Sensitive electrochemical detection of dopamine with a DNA/graphene bi-layer modified carbon ionic liquid electrode.
abstract: A DNA and graphene (GR) bi-layer modified carbon ionic liquid electrode (CILE) was fabricated by an electrodeposition method. GR nanosheets were electrodeposited on the surface of CILE at the potential of -1.3 V and then DNA was further deposited at the potential of +0.5 V on GR modified CILE. Electrochemical performances of the fabricated DNA/GR/CILE were carefully investigated. Then electrochemical behaviors of dopamine (DA) on the modified electrode were studied with the calculated electrochemical parameters. Under the optimized conditions, a linear relationship between the oxidation peak current and the concentration of DA was obtained in the range from 0.1 μmol/L to 1.0 mmol/L with a detection limit of 0.027 μmol/L (3σ). The modified electrode exhibited excellent reproducibility, repeatability, stability, validation and robustness for the electrochemical detection of DA. The proposed method was further applied to the DA injection solution and human urine samples determination with satisfactory results.
authors: Department of Precision Instrument, Tsinghua University, Beijing 100084, PR China.
authors: Xiaofeng
authors: X
authors: Wang
authors: Department of Precision Instrument, Tsinghua University, Beijing 100084, PR China.
authors: Zheng
authors: Z
authors: You
authors: Department of Orthodontics, Beijing Stomatological Hospital, Beijing 100050, PR China.
authors: Hailiang
authors: H
authors: Sha
authors: College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, Qingdao 266042, PR China.
authors: Yong
authors: Y
authors: Cheng
authors: College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, Qingdao 266042, PR China.
authors: Huanhuan
authors: H
authors: Zhu
authors: College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, Qingdao 266042, PR China. Electronic address: swyy26@hotmail.com.
authors: Wei
authors: W
authors: Sun
mesh_terms: D004247:DNA / Q000737:chemistry* / Q000648:ultrastructure; D004298:Dopamine / Q000032:analysis* / Q000737:chemistry / Q000652:urine; D055664:Electrochemical Techniques / Q000295:instrumentation / Q000379:methods*; D004566:Electrodes; D006108:Graphite / Q000737:chemistry*; D006801:Humans; D052578:Ionic Liquids / Q000737:chemistry*; D008855:Microscopy, Electron, Scanning; D015203:Reproducibility of Results
chemical_list: D052578:Ionic Liquids; D006108:Graphite; D004247:DNA; D004298:Dopamine
keywords: Carbon ionic liquid electrode; Differential pulse voltammetry; Dopamine; Grapheme; dsDNA