A sensitive voltammetric method for the determination of parathion insecticide

doi:10.1016/S0003-2670(99)00357-8

Analytica Chimica Acta

Volume 396, Issue 1, 13 September 1999, Pages 39-44

https://doi.org/10.1016/S0003-2670(99)00357-8 Get rights and content

Abstract

A sensitive voltammetric method is developed for the determination of parathion (φNO₂) using a Nafion^®-coated glassy carbon electrode. In this method, parathion is first irreversibly reduced from φNO₂ to φNHOH. The reversible peaks at around +0.33 V (versus Ag/AgCl) corresponding to a two-electron oxidation/reduction of hydroxylamine (φNHOH) to the nitroso (φNO) derivative were used for detection with square-wave voltammetry. The experimental parameters, such as, pH, film thickness, preconcentration potential, preconcentration time, and square-wave voltammetric parameters were optimized. Using this method, a linear calibration curve for parathion was obtained up to 15 μM range in pH 1.1 citrate buffer solution with a detection limit (S/N = 3) of 50 nM.

Introduction

Parathion (phosphorothioic acid O,O-diethyl O-(4-nitrophenyl) ester, φNO₂) and its substituted derivatives are widely used as agricultural insecticide and known to be toxic in nature [1]. In spite of its low volatility (157–162°C) and low solubility in water, leaching may occur especially in sandy soils. Qualitative and quantitative analysis of these materials is thus very important for environmental control [2]. Previous approaches used for the determination of parathion and its substituted derivatives include a flame photometric quantitative method [3], an enzyme immunoassay 4, 5, and an electrochemical method [6]. The major drawback of these methods is that they are time consuming and not suitable for routine analysis. For example, it takes 10 min of preconcentration time for the voltammetric determination of methyl parathion using a carbon paste electrode modified with C₁₈ to get a detection limit of 7.9 ng/ml. We report here a simple and easy electrochemical method for sensitive determination of parathion using a Nafion^®-coated glassy carbon electrode (NCGCE). Square-wave (SW) voltammetry was used for the quantitative estimation because this technique is superior for reversible systems 7, 8, 9.

Section snippets

Chemicals and reagents

Nafion^® perfluorinated ion-exchange powder, 5 wt.% solution in a mixture of lower aliphatic alcohol's and 10% water was obtained from the Aldrich. Parathion and all other compounds (ACS certified reagent grade) were used without further purification. Aqueous solutions were prepared with doubly distilled deionized water. Unless otherwise mentioned, a 0.1 M citrate buffer of pH 1.1 was used for all the electrochemical measurements. Groundwater and lake water were collected from the campus of

Electrochemical behavior of parathion on the NCGCE

Fig. 1 shows the continuous cyclic voltammetric (CV) response of 40 μM parathion on the NCGCE in pH 1.1 citrate buffer at a scan rate of 100 mV/s in the range of +0.6 V to −0.8 V. During the first cathodic sweep (switching potential at +0.6 V), one peak (C1) appeared at −0.4 V, and another one appeared at +0.35 V (A2) on the anodic sweep. In the successive cycles, in addition to C1, one new peak (C2) also appeared at +0.32 V in the cathodic sweep. It is interesting that the reversible redox couple at

Acknowledgements

The authors gratefully acknowledge the financial support from the National Science Council of the Republic of China under Grant NSC 88-2113-M-005-020.

References (11)

F. Mazzei et al.
Anal. Chim. Acta
(1996)
W.M. Draper et al.
Bull. Environ. Contam. Toxicol.
(1981)
D. Barcelo
Analyst
(1991)
R.E. Baynes et al.
J. Assoc. Anal. Chem.
(1985)
J.M. Wong et al.
J. Agric. Food Chem.
(1991)

There are more references available in the full text version of this article.

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A sensitive voltammetric method for the determination of parathion insecticide

Abstract

Introduction

Section snippets

Chemicals and reagents

Electrochemical behavior of parathion on the NCGCE

Acknowledgements

Anal. Chim. Acta

Bull. Environ. Contam. Toxicol.

Analyst

J. Assoc. Anal. Chem.

J. Agric. Food Chem.