title: Zeolite A functionalized with copper nanoparticles and graphene oxide for simultaneous electrochemical determination of dopamine and ascorbic acid.
abstract: A novel Cu-zeolite A/graphene modified glassy carbon electrode for the simultaneous electrochemical determination of dopamine (DA) and ascorbic acid (AA) has been described. The Cu-zeolite A/graphene composites were prepared using Cu(2+) functionalized zeolite A and graphene oxide as the precursor, and subsequently reduced by chemical agents. The composites were characterized by X-ray diffraction, Fourier transform infrared spectra and scanning electron microscopy. Based on the Cu-zeolite A/graphene-modified electrode, the potential difference between the oxidation peaks of DA and AA was over 200mV, which was adequate for the simultaneous electrochemical determination of DA and AA. Also the proposed Cu-zeolite/graphene-modified electrode showed higher electrocatalytic performance than zeolite/graphene electrode or graphene-modified electrode. The electrocatalytic oxidation currents of DA and AA were linearly related to the corresponding concentration in the range of 1.0×10(-7)-1.9×10(-5)M for DA and 2.0×10(-5)-2.0×10(-4)M for AA. Detection limits (<!-- no-mfc -->S/N<!-- /no-mfc -->=3) were estimated to be 4.1×10(-8)M for DA and 1.1×10(-5)M for AA, respectively.
authors: State Key Laboratory Cultivation Base for Nonmetal Composites and Functional Materials, School of Materials Science and Engineering, Southwest University of Science and Technology, Mianyang 621010, Sichuan, PR China. heping1971@yahoo.com.cn
authors: Ping
authors: P
authors: He
authors: Wei
authors: W
authors: Wang
authors: Licheng
authors: L
authors: Du
authors: Faqin
authors: F
authors: Dong
authors: Yuequan
authors: Y
authors: Deng
authors: Tinghong
authors: T
authors: Zhang
mesh_terms: D001205:Ascorbic Acid / Q000032:analysis*; D003300:Copper / Q000737:chemistry*; D004298:Dopamine / Q000032:analysis*; D055664:Electrochemical Techniques / Q000295:instrumentation* / Q000379:methods; D004566:Electrodes; D006108:Graphite / Q000737:chemistry; D057230:Limit of Detection; D053768:Metal Nanoparticles / Q000737:chemistry*; D008855:Microscopy, Electron, Scanning; D010087:Oxides / Q000737:chemistry; D017550:Spectroscopy, Fourier Transform Infrared; D014961:X-Ray Diffraction; D017641:Zeolites / Q000737:chemistry
chemical_list: D010087:Oxides; D017641:Zeolites; D006108:Graphite; D003300:Copper; D001205:Ascorbic Acid; D004298:Dopamine