title: Electrochemical determination of dopamine and ascorbic acid at a novel gold nanoparticles distributed poly(4-aminothiophenol) modified electrode.
abstract: A modified electrode is fabricated by embedding gold nanoparticles into a layer of electroactive polymer, poly(4-aminothiophenol) (PAT) on the surface of glassy carbon (GC) electrode. Cyclic voltammetry (CV) is performed to deposit PAT and concomitantly deposit Au nanoparticles. Field emission transmission electron microscopic image of the modified electrode, PAT-Au(nano)-ME, indicates the presence of uniformly distributed Au nanoparticles having the sizes of 8-10nm. Electrochemical behavior of the PAT-Au(nano)-ME towards detection of ascorbic acid (AA) and dopamine (DA) is studied using CV. Electrocatalytic determination of DA in the presence of fixed concentration of AA and vice versa, are studied using differential pulse voltammetry (DPV). PAT-Au(nano)-ME exhibits two well defined anodic peaks at the potential of 75 and 400mV for the oxidation of AA and DA, respectively with a potential difference of 325mV. Further, the simultaneous determination of AA and DA is studied by varying the concentration of AA and DA. PAT-Au(nano)-ME exhibits selectivity and sensitivity for the simultaneous determination of AA and DA without fouling by the oxidation products of AA or DA. PAT and Au nanoparticles provide synergic influence on the accurate electrochemical determination of AA or DA from a mixture having any one of the component (AA or DA) in excess. The practical analytical utilities of the PAT-Au(nano)-ME are demonstrated by the determination of DA and AA in dopamine hydrochloride injection and human blood serum samples.
authors.affiliation: Advanced Analytical Science and Nanomaterials Lab, Department of Chemistry Education, Kyungpook National University, Daegu 702-701, South Korea; Nano Practical Application Center, Daegu 704-230, South Korea; Department of Industrial Chemistry, Alagappa University, Karaikudi-630 003, India.
authors.forename: Anantha Iyengar
authors.initials: AI
authors.lastname: Gopalan
authors.forename: Kwang-Pill
authors.initials: KP
authors.lastname: Lee
authors.forename: Kalayil Manian
authors.initials: KM
authors.lastname: Manesh
authors.forename: Padmanabhan
authors.initials: P
authors.lastname: Santhosh
authors.forename: Jun Heon
authors.initials: JH
authors.lastname: Kim
authors.forename: Jae Soo
authors.initials: JS
authors.lastname: Kang