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An novel poly(graphene-methylmethacrylate-ethylene glycol dimethylacrylate)(G-MMA-EGDMA)pipette-tip solid phase sorbent was prepared by cryogel process to extract triazine herbicides for HPLC analysis in order to increase the extraction efficiency and reduce the flow resistance.In the preparation of modified graphene polymer,the acrylate functional group was first modified on the graphene oxide,then mixed with methyl methacrylate and ethylene glycol dimethacrylate for cryogel polymerization in dimethyl sulfoxide(DMSO)at 0.5oC.The modified graphene oxide was characterized with FT-IR and SEM image.Parameters affecting the extraction efficiency such as the pH of sample solution,the salt addition,the flow-rate for sample loading,rinsing solution and desorption solution were investigated thoroughly.Results indicate that the optimal conditions for PT-SPE of triazine herbicides in 5 mL of aqueous solution at pH 7 with 0.2%NaCl can be obtained with the flow-rate of 3 mL/min for sample loading,then rinsed with 1 mL of pure water,and eluted with 300 μL of acetone for the analysis with HPLC-UV.Under the optimal conditions,the limit of determination(LOD)and limit of quantitation(LOQ)for triazine herbicides were below 0.4 ng/mL and 1 ng/mL,respectively.It only took less than 5 min for the PT-SPE of triazine herbicides.The relative standard deviations(RSD)were less than 7.8%.Recovery were between 90.6-103.5%with RSD less than 9.3%.These results indicated that the poly(G-MMA-EGDMA)based PT-SPE has been successfully prepared by cryogel process and can be a rapid,sensitive,and eco-friendly sampling method.