In situ self-assembly of three-dimensional porous graphene film on zinc fiber for solid-phase microextraction of polychlorinated biphenyls.

Three-dimensional porous graphene film (3DPGF) was fabricated on Zn fiber for solid-phase microextraction (SPME) through in-situ self-assembly strategy at room temperature. Fast electron transfer due to ionization of zinc induces reduction of graphene oxide and thus leads to the layer-by-layer interfacial deposition of graphene sheets, forming three-dimensional porous network morphology. The 3D interpenetrating porous structure could provide more available adsorption site for the target molecules and also enhance mass transfer efficiency in the extraction process. Therefore, the obtained 3DPGF fiber exhibited excellent performance when applied in the SPME of preconcentration and quantification of polychlorinated biphenyls (PCBs) in environment waters. The developed method showed a linear range from 1.0 ng L-1 and 200 ng L-1 with an acceptable correlation (R2=0.990). The limit of detection (LOD) and limit of quantification (LOQ) were found 0.03-0.2 ng L-1 and 0.1-0.8 ng L-1, respectively. The proposed method was applied in real water samples analysis with the recoveries ranging from 63.1 to 111.3%. The present study expanded the application of three-dimensional porous graphene materials in sample preparation and revealed its potential in SPME application.