Melamine can be introduced into environment via various industrial effluents, thus it is necessary to develop suitable analytical methods for determination of melamine in environmental samples. In this work, magnetic graphene oxide (MGO) was synthesized and used as the adsorbent for solid phase extraction of melamine. The parameters that affect the extraction efficiency of melamine were investigated. The optimum conditions, including sample pH, extraction and desorption time, and eluent volume were obtained. The analytical performance of the method was investigated, and it was found that the limit of detection (LOD) for melamine was 0.15μg/L and the RSD was 3.6 %. The proposed method was utilized in the determination of melamine in environmental water samples with recoveries were higher than 92%.

Bisphenol A (BPA) has received much attention from the public due to its endocrine disrupting effect. Therefore it is necessary to develop suitable analytical methods for determination of bisphenol A in water samples. In this study, magnetic graphene oxide was prepared and used as the sorbent for magnetic solid phase extraction of bisphenol A from aqueous solutions. The parameters which influence the extraction efficiency of bisphenol A were investigated. The optimum conditions, such as sample pH, extraction and desorption times, and eluent type and volume were obtained. The analytical performance of the method was evaluated, and the results showed that the limit of detection (LOD) for bisphenol A was 0.36μg/L and the RSD was 2.9 %. The developed method was applied to the detection of bisphenol A in environmental water samples with satisfactory recoveries. 1