Microwave‐assisted preparation of magnetic nanoparticles modified with graphene oxide for the extraction and analysis of phenolic compounds

Here in, magnetic nanoparticles combined with graphene oxide adsorbent were fabricated via a microwave‐assisted synthesis method, and used in the solid‐phase extraction of three phenolic compounds (phenol, 4‐nitrophenol, and m‐methylphenol) in environmental water samples. Various instrumental methods were employed to characterize the magnetic nanoparticles modified with graphene oxide. The influence of experimental parameters, such as desorption conditions, amount of adsorbent, extraction time, and pH, on the extraction efficiency was investigated. Owing to the high surface area and excellent adsorption capacity of the prepared material, satisfactory extraction was achieved. Under optimum conditions, a linear response was observed in the concentration range of 1.000–100.0 μg/L for phenol, 0.996–99.6 μg/L for 4‐nitrophenol, and 0.975–97.5 μg/L for m‐methylphenol, with correlation coefficients in the range of 0.9995–0.9997. The limit of detection (signal‐to‐noise ratio of 3) of the method varied between 0.5 and 0.8 μg/L. The relative standard deviations were <5.2%. The recovery percentages of the method were in the range of 89.1–104.3%. The results indicate that the graphene oxide‐modified magnetic nanoparticles possess high adsorptive abilities toward phenolic compounds in environmental water samples.