文档介绍：ORIGINAL PAPER Electrocatalytic determination of sulfite using a modified carbon nanotubes paste electrode: application for determination of sulfite in real samples Hassan Karimi-Maleh &Ali A. Ensafi &Hadi Beitollahi & Vahid Nasiri &Mohammad A. Khalilzadeh & Pourya Biparva Received: 13 November 2010 / Revised: 12 November 2011 / Accepted: 11 December 2011 / Published online: 7 January 2012 # Springer-Verlag 2011 Abstract This paper introduces a carbon paste electrode modified with ferrocene and carbon nanotubes as a voltam- metric sensor for determination of sulfite at pH . The results showed that under the optimum condition (pH ) in cyclic voltammetry, the oxidation of sulfite occurred at a potential about 280 mV less positive than the unmodified carbon paste electrode. ic parameters such as electron transfer coefficient ( α) and heterogeneous rate constant ( k ) for sulfite were also determined using electrochemical approaches. Under the optimized conditions, the electrocata- lytic oxidation peak current of sulfite showed two linear dynamic ranges with a detection limit of μM for sulfite. The proposed method was examined as a selective, simple, and precise method for voltammetric determination of sulfite in some real samples such as weak liquor from wood and paper industry, boiler water, river water, industrial water, and tap water. Keywords Sulfite .Carbon nanotub