The use of deep eutectic solvent coated graphene oxide in dispersive solid phase extraction and its combination with dispersive liquid-liquid microextraction for the extraction of some pesticides from aqueous samples

Abstract

The industrialization of agriculture and the use of pesticides in recent decades have caused an increase in the pollution of water sources. Due to the adverse effects of these pollutants on human health and the environment, it is necessary to develop methods to remove them from water sources. Pesticide residue control in water samples is mainly done by GC methods, which have high efficiency.Expression of purpose: In this research work, diffusion solid phase extraction based on graphene oxide adsorbent coated with deep tectic solvents was used to extract pesticides from water samples with gas chromatography equipped with a flame ionization detector (GC-FID). Method: First, graphene oxide particles were synthesized, and then these particles were used with a deep tectic solvent to modify the absorption properties of these particles. Then, to check the amount of pesticide absorption by the adsorbent, the pesticide solution was vortexed with the adsorbent, and the amount of absorption was measured by a GC-FID device.Results: The proposed method was optimized by "one parameter at a time" method and then validated. The LOD was in the range of 0.5 to 0.9 ng/mL, and the LOQ was in the range of 1.7 to 3.2. The EF was in the range of 364 to 422 and the ER was in the range of 73 to 84%, which shows the high efficiency of the proposed method.Discussion and conclusion:In this research work, a new extraction method called solid phase dispersion was introduced to extract pesticides from drinking and surface water samples. In order to achieve high concentration factors, the DLLME method was used, and then it was taken from the GC-FID device for quantitative analysis. Reduced graphene oxide with deep eutectic solvents is used as an adsorbent. According to the results, the adsorbent has effectively absorbed the target pesticides.