Preparation and application of graphene oxide-based surface molecularly imprinted polymer for monolithic fiber array solid phase microextraction of organophosphate flame retardants in environmental water.

Selectivity and high throughput are important for determination of trace level of various organophosphate flame retardants (OPFRs) in environmental matrices. In this work, three selective monolithic fibers for solid phase microextraction (SPME) were prepared and evaluated. They are graphene oxide (GO)-based surface trimethyl phosphate (TMP) imprinted polymeric fiber (GO/TMP-IPF), GO-based surface tri (2-chloroethyl) phosphate (TCEP) imprinted polymeric fiber (GO/TCEP-IPF) and GO-based surface triphenyl phosphate (TPhP) imprinted polymeric fiber (GO/TPhP-IPF). The imprinting factors of GO/TMP-IPF for TMP, GO/TECP-IPF for TCEP and GO/TPhP-IPF for TPhP were tested as high as 4.3, 4.5, 10.3, respectively. The three fibers were bound to a stainless steel wire to assemble a GO-based surface molecularly imprinted polymeric fiber array (GO/MIP-FA). GO/MIP-FA-SPME device was coupled to gas chromatography-flame photometric detector and carried out simultaneous determination of TMP, TCEP and TPhP in environmental water. Under the optimal conditions, ultralow limits of quantification (1.7 ng L-1-5.0 ng L-1); linearity (>0.99); intra- and inter-day precision expressed as relative standard deviations for an array in the range of 4.9-8.6% and 5.8-8.2%, respectively, and array-to-array reproducibility in the range of 7.2-9.1% were obtained. The GO/MIP-FA-SPME technique was successfully applied for the determination of OPFRs in various environmental water samples, and the relative recoveries were found to be in the range from 72.4 to 112.0%.