Analytical Sciences

Abstract − Analytical Sciences, 19(4), 511 (2003).

Differential Pulse Adsorptive Stripping Voltammetric Determination of Dinoseb and Dinoterb at a Modified Electrode
Mallipattu SREEDHAR, Tukiakula Madhusudana REDDY, Kami Reddy SIRISHA, and Srinivasulu Reddy Jayarama REDDY 
Electrochemical Research Laboratories, Department of Chemistry, Sri Venkateswara University, Tirupati-517 502, India
A sensitive adsorptive stripping voltammetric method for the determination of dinitrophenolic herbicides, dinoseb (DSB) and dinoterb (DTB) at a bare carbon paste electrode (CPE) and a clay modified carbon paste electrode (CMCPE) was developed. A systematic study of various experimental conditions, such as the pH, accumulation variables and composition of a modifier on the adsorptive stripping response, were examined by using differential pulse voltammetry. A significant improvement was observed in the sensitivity by using the present method with CMCPE. When CMCPE was used, a linear response was obtained over the concentration range 2 x 10-10 to 3 x 10-7 M and 6 x 10-10 to 6 x 10-7 M with lower detection limits of 1 x 10-10 M and 5.4 x 10-10 M for dinoseb and dinoterb, respectively, at an accumulation time of 100 s. The interference from other herbicides and ions on the stripping signals of both compounds was also evaluated. The described method was applied to estimate of the dinoseb and dinoterb in environmental samples.