Voltammetric Determination of Herbicide Triasulfuron using Mercury Meniscus Modified Silver Solid Amalgam Electrode

Voltammetric behavior of triasulfuron (TS), which belongs to sulfonylurea herbicide family, was studied using two working electrodes: mercury meniscus modified silver solid amalgam electrode (m-AgSAE) and hanging mercury drop electrode (HMDE) for comparison. It was found that TS provided one reduction peak on both used working electrodes. The highest response was observed in the environment of Britton-Robinson buffer (BR) of pH 3 (m-AgSAE) and 2.5 (HMDE), respectively. Working parameters of differential-pulse voltammetry (DPV) were optimized and this method was applied in analysis of agricultural formula and river water

Voltammetric Behavior of Folates and Related Substances Using Silver Solid Amalgam Electrode

The possibility of application of silver solid amalgam electrode in voltammetric analysis of compounds with folate structure (folic acid, methotrexate, leucovorin) and substances, which play an important role in its metabolism (riboflavin, hydroxocobalamin) has been investigated. Cyclic voltammetry, DC voltammetry and Elimination voltammetry with linear scan has been used for study of voltammetric behavior of mentioned substances and for elucidation of electrochemical reactions. Differential pulse voltammetry has been applied for development of sensitive methods of determination for investigated electroactive compounds. The proposed methods were successfully applied for real samples analysis. Obtained results have been compared with those achieved using HMDE

Citlivá voltametrická metoda stanovení herbicidu metribuzinu s využitím stříbrné pevné amalgámové elektrody

New sensitive voltammetric method for determination of triazinone herbicide metribuzin (MTZ) was developed employing polished and mercury meniscus-modified silver solid amalgam electrode (p-, m-AgSAE). MTZ yielded two reduction signals on both used working electrodes in acidic and slightly acidic media and the positively situated peak [at about -650 mV vs. Ag|AgCl|KCl (sat.)] was found suitable for further analytical measurements. The highest responses were recorded in Britton-Robinson buffer of pH 2 (p-AgSAE) or 3 (m-AgSAE). Various voltammetric techniques like cyclic, linear sweep, and differential pulse voltammetry were used for examination of the voltammetric behavior of MTZ. Parameters of differential pulse voltammetry were optimized and low detection limits were reached (LODm-AgSAE = 6.0 x 10(-8) mol dm(-3) and LODp-AgSAE = 7.5 x 10(-8) mol dm(-3)). Moreover, excellent repeatability of determination and measurements as well was confirmed by low values of relative standard deviations of five repeated determinations [RSD (5) a parts per thousand currency sign 6.0 %] and of 11 repeated measurements [RSD (11) a parts per thousand currency sign 4.5 %], respectively. Finally, practical applicability of newly proposed methods was verified by the analysis of spiked tap and river water and by determination of MTZ in pesticide preparation with excellent results. All the obtained results were compared with those gained for classic mercury electrode.Bylo studováno voltametrické chování herbicidu metribuzinu s využitím stříbrné pevné amalgámové elektrody a byla vyvinuta metoda stanovení této látky. Ta byla splikována při analýze přírodních vod a pesticidního přípravku