Voltammetric sensor development and characterization for the determination of phenylurea herbicides

In this thesis, imprinting of phenylurea herbicides by electrochemical polymerization on single used pencil graphite electrodes was implemented for the first time in the literature. For this purpose, electrochemical behaviors of phenylurea herbicides, monuron or metoxuron, were examined and it was seeing and decided that p-phenylenediamine was the best appropriate monomer for electrochemical polymerization after having determined the optimum polymerization conditions (rate of polymer film growth, pH of the medium, mole ration of monomer/template molecule, polymer film thickness) molecular imprinted polymers were electropolymerized on pencil graphite electrodes. Afterwards, leaching of template from the polymer matrix by chronoamperometry was studied. Following the step, in order to specify the performance of the sensors back-binding studies by means of wet adsorption were realized. It was seen that the maximum binding were occurred by both molecules at 10-3 M concentration at 60 s. Employing sensors that templates were leached at optimum conditions selectivity studies were performed in the presence of some analogues molecules (propanil, 3,4-dichloroaniline, urea, diuron) and it was seeing that selectivity of the developed sensors towards this analogues were acceptable high. Furthermore, the responses of the developed sensors were tested on a synthetically prepared agriculture herbicide samples spiked with monuron and metoxuron.