M. Zimpl, M. Kotouček, K. Lemr
Dec 1, 2001
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0
Influential Citations
7
Citations
Journal
Fresenius' Journal of Analytical Chemistry
Abstract
Abstract. The electrochemical behavior of the herbicide chloridazon, I (pyrazon), at different pH is described. The electrode reaction (one wave in acidic media and another in alkaline media), investigated using direct current and pulse voltammetry, controlled–potential coulometry, and HPLC–MS, is a combination of the electroreduction (two-electron in the first step) and a kinetic process as a result of which simple compounds (HCl, NH3) are released and, moreover, a five-membered pyrrole cycle is formed in strongly acid media. Products of the kinetic reaction are further reducible. The dissociation constant of I, pKa=2.96, was found spectrophotometrically. Fast-scan differential pulse voltammetry (FSDPV) was used for determination of I; the detection limit was 2.7×10–8 mol L–1 (0.006 µg L–1) at pH 2.3. Chloridazon was determined in spiked drinking and river water.