Applications analytiques des films minces de mercure protégés par du fibrinogène pour la détermination du plomb et du cadmium dans des échantillons d’eaux usées et d’eaux de mer

Abstract

Analytical application of fibrinogen-coated mercury film electrodes for the detection of lead and cadmium in water samplesThe aim of this study was the development of sensor based on fibrinogen (Fbg) coated mercury film electrodes at carbon paste electrode in the perspective of in-field stripping analysis of heavy metals in complex matrix. The preparation, optimization and characterization of coatings of Fibrinogen (Fbg) for the modification of thin mercury film electrodes and its application for the detection of trace metals have been described . The modified carbon paste electrode was prepared by a simple adsorption of fibrinogen from an aqueous solution containing an adequate quantity of fibrinogen. The Mercury film was then prepared by electrodeposition through the fibrinogen coating. The experimental parameters such as concentration of fibrinogen, deposition time and deposition potential were investigated. The performance of this electrode is evaluated in a presence of different surfactants such as gelatine, albumin, SDS and Tween 20, while lead and cadmium were employed as test metal ions. Using selected conditions the limits of detection were 5.10-9 mol.L-1 and 2.10-8 mol.L-1 for lead and cadmium, respectively. Since fibrinogen coated mercury film showed the best performance and increased efficiency against surfactants when comparing to the conventional mercury film, it was used for the analysis of trace metals in environmental samples of waters and industrial effluents.