Porous agarose/chitosan/graphene oxide composite coupled with deep eutectic solvent for thin film microextraction of chlorophenols

Abstract

In this project, a three-dimensional graphene oxide coated agarose/chitosan (ACGO) porous film was synthesized and utilized as sorbent in thin film microextraction (TFME) technique to extract 4-chlorophenol, 2,4-dichlorophenol, 3,5-dichlorophenol and 2,4,6-trichlorophenol as the model analytes in various real samples such as agricultural waste water, honey and tea samples. In addition, deep eutectic solvent made of tetra ethyl ammonium chloride/chlorine chloride was used as a desorption solvent. The effect of various variables, such as: extraction time, stirring rate, solvent desorption volume, desorption time, ionic strength and solution pH on the extraction efficiency of the method was studied and optimized. Under the optimized condition, the linear range of the method was obtained in the range of 0.1–500μgL−1 for testing analytes (4-chloropheol=0.1-500μgL−1, 2,4-dichlorophenol=0.2-500μgL−1, 3,5-dichlorophenol=0.5-500μgL−1 and 2,4,6-trichlorophenol=0.2-500μgL−1). The obtained correlation coefficients (r2) were between 0.9984 and 0.9994. The limits of detection (LODs) were also calculated between 0.03 - 0.13μgL−1. The relative standard deviations (RSDs%) were obtained in the range of 2.8 to 5.9%. The enrichment factor (EFs) values for the studied analytes were also obtained in the range of 33.4-35.8. In addition, the obtained results indicated that the prepared film can potentially be used for more applications in the field of environment, food safety, and drug analysis.