Development of microelectrode arrays modified with inorganic – organic 3 composite materials for dopamine electroanalysis

23 New electrode materials based on composite inorganic redox material–organic conducting polymer for 24 electroanalysis of dopamine were developed. The composite inorganic–organic coatings based on Prus25 sian blue (PB) and poly(3,4-ethylenedioxythiophene) (PEDOT) have been prepared by electrochemical 26 methods onto gold disk microelectrode arrays. Both insoluble and soluble forms of PB were prepared 27 in situ inside the organic matrix and their electrochemical behaviour was investigated in electrolyte solu28 tion. The composite inorganic–organic coating containing the soluble PB form exhibited good electrocat29 alytic activity towards dopamine (DA) oxidation in aqueous buffered solutions. The DA concentration was 30 determined by cyclic voltammetry in the presence of a high excess of ascorbic acid (AA). A linear response 31 for DA concentrations ranging from 10 lM to 50 lM, in the presence of 1 mM AA, with a sensitivity of 32 460 lA/lM and a detection limit of 4.3 lM, have been obtained. 33 2009 Published by Elsevier B.V.