Silicate electrochemical measurements in seawater: Chemical and analytical aspects towards a reagentless sensor
|Author(s)||Lacombe Marielle1, Garcon Veronique1, Thouron Daniele1, Le Bris Nadine2, Comtat Maurice3|
|Affiliation(s)||1 : CNRS, Lab Etud Geophys & Ocenog Spatiales, UMR 5566, F-31401 Toulouse 9, France.
2 : IFREMER, Dept Etud Ecosyst Profonds, F-29280 Plouzane, France.
3 : Univ Toulouse 3, Lab Genie Chim, UMR 5503, F-31062 Toulouse, France.
|Source||Talanta (0039-9140) (Elsevier), 2008-12 , Vol. 77 , N. 2 , P. 744-750|
|WOS© Times Cited||13|
|Keyword(s)||Cyclic voltammetry, Amperometry, Reagentless, Silicate, Molybdenum|
|Abstract||From the study of molybdenum oxidation in aqueous solutions we developed a semi-autonomous method to detect silicate in aqueous samples. Molybdenum oxidation was used to form molybdate in acidic media. The silicomolybdic complex formed with silicate is detectable by amperometry or cyclic voltammetry. The new electrochemical method is in good agreement with the method conventionally used for environmental water silicate analysis. In the second stage, a completely reagentless method was developed using molybdate and proton produced during molybdenum oxidation. Reproducibility tests show a precision of 2.6% for a concentration of 100 mu mol L-1. This new method will be Very Suitable for the development of new autonomous silicate sensors easy to handle and without reagents. In this paper we present the analytical and chemical aspects necessary for a complete documentation of the method before the development of a new reagentless sensor. (C) 2008 Published by Elsevier B.V.|