All-solid-state surfactant sensing electrode using conductive polymer as internal electric contact

An all-solid-state anionic surfactant electrode type was developed using te flonized graphite rods coated with electrochemically prepared polypyrrole f ilm as electric connector support. The measuring membrane of the electrodes was made of ion-pairs formed with the appropriate anionic and cationic sur factants incorporated into plasticized poly(vinylchloride) film. Preparatio n procedure for the ion-pair is described briefly in the text. The electroc hemical properties of the electrode were studied and the function of the el ectrode was tested. Due to the well defined charge transfer mechanisms at t he graphite-polypyrrole-membrane interfaces the surfactant electrode showed good stability. The lower limit of detection was in the range of 0.5-1 muM in case of the different surfactants tested. Due to the relatively fast re sponse time and the good stability of the electrode, a sample rate of 30 sa mple/h in flow-injection determinations could be achieved. (C) 2001 Elsevie r Science B.V. All rights reserved.