Method For Determination Of Malathion Research Articles

Rapid resolution liquid chromatography method for determination of malathion in pesticide formulation

This paper presents a new, simple, precise, and accurate rapid resolution liquid chromatography (RRLC) method for determination of an active ingredient malathion in the pesticide formulation. The analysis was performed on a Poroshell EC 120-C18 (50 mm × 3 mm, 2.7 μm) analytical column using isocratic elution with a mobile phase consisted of acetonitrile–water (50:50, v/v), a flow rate of 1 mL/min, a constant column temperature at 25 °C, and ultraviolet-diode array detection (UV-DAD) at 220 nm. The specificity, selectivity, linearity, precision, and accuracy were tested for the method validation according to the Collaborative International Pesticides Analytical Council (CIPAC) and Directorate General Health and Consumer Protection (SANCO) guidelines and all tested parameters were found within acceptance criteria. The obtained results indicated that the proposed method can be used for routine analysis of the active ingredient malathion in the pesticide formulation “Etiol tecni” following the CIPAC and SANCO rules. The run time of analysis under the stipulated chromatographic conditions was about 2.5 min, meaning that the proposed method requires a small volume (< 1.5 mL) of the organic solvent (acetonitrile) making it cost-effective.

A convenient method for determination of malathion based on the resonance Rayleigh scattering enhancement

A convenient method for determination of malathion (Mala) based on resonance Rayleigh scattering (RRS) enhancement of L-Tryptophan (L-Try)-Pd(II)-Mala system was proposed in this paper. The interaction between L-Try, Pd(II) and malathion in the system was investigated by fluorescence, RRS and UV–Vis absorption spectroscopy. In the optimum conditions, the RRS intensity of L-Try-Pd(II)-Mala system had a remarkable enhancement because the hydrolysis products of malathion would interact with Pd(II) and L-Try each other formed new complexes, which enhanced intensity was directly proportional to the malathion concentration within a certain range. Based on the RRS enhancement of L-Try-Pd(II) system by Mala, a novel, convenient and specific method for Mala determination was developed. To our knowledge, the method is the first RRS method for determination of Mala was reported. The detection limit for Mala was 6.7 ng/mL and the quantitative determination range was 0.06–0.6 μg/mL. The influence of coexisting substances on RRS was also investigated, and the RRS method exhibited good anti-interference ability. The new analytical method has been applied to determine of malathion in real samples with satisfactory results.

Nonaqueous Copper Colorimetric Method for Determination of Malathion in Technical Grade Malathion and in Malathion Formulations

Abstract A nonaqueous copper colorimetric procedure has been developed for the assay of technical and formulated products of malathion. The stability of the copper O,O-dimethyl phosphorodithioate complex has been substantially improved by the use of nonpolar solvents and by lowering the hydrogen ion activity of the system. This has permitted the elimination of the partitioning step and has relaxed the critical timing requirements specified in the offi cial first action AOAC method. The new method has a precision of ±1.6% at a 95% confidence level. The accuracy of the technique is discussed in terms of various minor interferences and by contrasting the results obtained with alternative assay methods.

Argentimetric Method for Determination of Malathion in Formulations

Abstract A method has been developed for the determination of malathion in technical grade products by argentimetric titration of the dimethylphosphorodithioate ion formed by alkaline cleavage of the molecule. Free dimethylphosphorodithioic acid and other polar impurities are removed by a column of cellulose powder containing 30% moisture. Malaoxon, isomalathion, and diethylmercaptosuccinate do not interfere. However, the methyl ethyl ester of malathion, if present, will titrateasmalathion . The method has been adapted to the analysis of formulations of emulsifiable concentrates, water-dispersible powders, and dusting powders. The analyses can be performed potentiometrically by titration to a fixed millivoltage, using a pH meter, or with anautomatic titrator operated in the derivative mode. When the method was applied to samples of technical grade malathion, the standard deviation varied from 0.21 to 0.42%.