An experimental design approach to the optimisation of pesticide extraction from water

Abstract

In the last few decades, pesticides have been used increasingly throughout the world. Nowadays, contamination of aquatic systems by pesticides has become a global problem. Due to their stability, mobility and long-term effects on living organisms, pesticides are among the most dangerous pollutants that can be monitored in the environment, and the determination of accurate contamination levels also constitutes a crucial step in environmental research. However, in the case of quantitative analyses, extraction of targeted analytes can turn out to be difficult since these compounds are often present below the detection limits. Consequently, the accuracy of environmental analyses mainly depends on the efficiency and the robustness of the extraction–preconcentration step. In this work, a solid-phase extraction (SPE) procedure using hydrophilic modified styrene-based polymer (HLB) cartridges was optimized for the extraction of organonitrogen and organochlorine pesticides from water. An experimental design was carried out for modeling SPE optimal extraction conditions of thirty four pesticides. The five parameters studied were the flow rate, pH, elution speed, ionic strength of the sample and the nature of the eluting solvent. Extracts were analyzed using gas chromatography equipped with a mass spectrometer (GC-MS). The optimal extraction conditions selected for the flow rate, pH, elution speed, ionic strength and the nature of the eluting solvent were respectively 2–4 mL min⁻¹, pH = 6, 0.5 mL min⁻¹, 100 g L⁻¹ of NaCl and ethyl acetate–methanol (1/1 v/v). The analytical procedure was validated for fifteen pesticides, which include thirteen organonitrogens and two organochlorines

Chemometric Optimization of SPE for the Determination of Multiclass Pesticides in Portable Water Samples by UHPLC-MS/MS

“…Experimental design was conducted to decrease the number of experiments during the optimization of the SPE parameters and to assess the interaction between the variables (El-Osmani et al 2014 ). The main factors influenced the SPE efficiency include sample volume, sample pH value, the volume and the elution solvent composition.…”

A review of the modern principles and applications of solid-phase extraction techniques in chromatographic analysis

“…Results from the Soxhlet extraction procedure were compared with those from SPE. SPE cartridges embedded with HLB copolymers and GC–MS were also used to quantify pesticide concentrations in Northern Lebanon after OCPs were isolated and trace-enrichment was carried out from water samples [ 168 ].…”

Pesticide distribution and ecotoxicological risk in the Ayuquila-Armería river

“…Elution of the analytes was conducted with 6 mL of MeOH. The samples were evaporated at 1 mL at ambient temperature, according to the procedure published by El-Osmani et al (2014). The final extract was placed in 2 mL vials for injection into the liquid chromatography.…”