Differential Pulse Polarographic Analysis of Chlorpyrifos Insecticide

Abstract

The differential pulse polarographic (DPP) behavior of chlorpyrifos (CP) was investigated over a wide range of pH (pH 1.8-pH 10.1). CP compound displays a well-resolved cathodic reduction peak at ¹1.2 V (vs. Ag/AgCl) (pH 3.2). This peak probably corresponds to the reduction of the --C=N-centre of the pyridyl moiety. The effect of solution and operational parameters on the sensitivity of the DPP peak was carefully examined in order to select the optimum conditions for determination of the CP compound. Under the optimum conditions the reduction response gives a linear calibration plot over a concentration range of 9.70 × 10 ¹7 -6.92 × 10 ¹6 M and the detection limit was found to be 8.7 × 10 ¹7 M. The effects of some diverse metal ions, anions and some other organophosphorus insecticides on the determination of CP compound were studied. The applicability of DPP for determination of the CP insecticide in a commercial sample as well as in some irrigation water (treated waste water and underground water) was detected.

Development of an adsorptive catalytic stripping voltammetric method for the determination of an endocrine disruptor pesticide chlorpyrifos and its application to the wine samples

“…Although catalytic currents are usually of poor reproducibility, they do offer greater sensitivity as the magnitude of the current is two orders larger than that of diffusion currents. This mechanism differs from that proposed earlier [40,41] and implies the high sensitivity of the method. Lower ethanol percentages utilized in this study would also contribute to the sensitivity as it affects the adsorption characteristics.…”

“…To investigate the effect of pH on the peak shape, the analysis was carried out in BR buffer solutions over a pH range of 2.0 to 10.0 each containing 25% ethanol as described earlier [40]. Figure 1 illustrates the dependence of the peak height of the CP on the pH.…”

“…Chlorpyrifos is known to be electroactive and its differential pulse polarographic (DPP) behavior was investigated [40]. Adsorptive property of the molecule was utilized in stripping voltammetric determination of CP in commercial formulations and treated waste water samples [41].…”

Determination of insecticide pymetrozine by differential pulse polarography/application to lake water and orange juice☆

“…So far, chromatographic techniques have been the most widely used for the determination of various insecticides [4][5][6], but electroanalytical techniques have also been used for the determination and studying several insecticides in different matrices like water, soils, plants and food [7][8][9]. So, the voltammetric methods are increasingly used for the determination of biologically active substances, including pesticides; these methods offer sufficiently low detection limits, broad intervals of contents determined, and selectivity.…”

Recent Applications of Mercury Electrodes for Monitoring of Pesticides: A Critical Review

“…This radical is further reduced in the second step involving one electron and one proton. Similarly, chlorpyrifos can be determined at HMDE .…”