Fabrication of magnetic microsphere-confined graphene for the preconcentration of some phthalate esters from environmental water and soybean milk samples followed by their determination by HPLC

► A magnetic microsphere-confined graphene, Fe3O4@SiO2-G, was fabricated by the chemical bonding method for the first time. ► Fe3O4@SiO2-G was used as an adsorbent for the preconcentration of some phthalate esters in water and soybean milk samples. ► The sorbent was stable enough and could be a promising adsorbent for MSPE.