Dispersive Solid-phase Microextraction With Graphene Oxide Based Molecularly Imprinted Polymers For Determining Bis(2-ethylhexyl) Phthalate In Environmental Water

Bis?2-ethylhexyl?phthalate is known as the most common used plasticizer,especially in plastic goods.At present,it also plays a role to be the environmental estrogen,which really affects the human bodies and many other creatures.Actually,DEHP now has been determined in many occasions,like environmental water,gas,soil,and living organism.Here A graphene oxide?GO?based molecularly imprinted polymers?MIPs?were prepared as the selective dispersive solid phase microextraction?DSPME?sorbents for specific recognition and sensitive detection of DEHP in water samples.In this work,DEHP was used as the template molecule,and methacrylic acid?MAA?was used as the functional monomertoenhancetheadsorptioncapacity,ethyleneglycol dimethacrylate?EGDMA?was added as the cross-linker,and later methylacryloyl-?-CD and methacrylic acid?MAA?were selected as dual functionalmonomerstoenhancetheadsorptioncapacity,methylacryloyl-?-CD was synthesized by?-CD with methacryloyl chloride through esterification reaction.The GO-MIPs?GO-MIPs-?-CD?mentioned above were characterized by scanning electron microscope?SEM?,Raman spectrum,Thermogravimetric analysis?TGA?and Fourier transform infrared spectroscopy?FTIR?.The optimized conditions of the GO-MIPs-?-CD was evaluated through various factors such as desorption solvent types and volume,adsorbent amount,pH,ionic strength,sample volume and material types.Under optimized conditions,DEHP can be selectively and effectively extracted with the imprinted factor of more than 100-fold.The linearity of GO-MIPs-DSPME reveals good correlation coefficients?R²?more than 0.999,with the limit of detection?LOD?of0.92 ng mL^-1.The average recoveries of the spiked samples at three concentration levels of DEHP ranged from 82%to 92%,and the relative standard deviations was less than 6.7%.The analytical performance of the GO-MIPs-?-CD-SPE method was determined with different spiked level of 0.5,1,4?g mL^-1,the average recoveries were found to be 84%⁸7.7%?RSD=1.5%⁵.7%,n=3?.The results performed by the two adsorbents were confirmed to be applied in detecting DEHP from water samples.