title: Evaluation of graphene as an advantageous adsorbent for solid-phase extraction with chlorophenols as model analytes.
abstract: Graphene, a novel class of carbon nanostructures, possesses an ultrahigh specific surface area, and thus has great potentials for the use as sorbent materials. We herein demonstrate the use of graphene as a novel adsorbent for solid-phase extraction (SPE). Eight chlorophenols (CPs) as model analytes were extracted on a graphene-packed SPE cartridge, and then eluted with alkaline methanol. The concentrations in the eluate were determined by HPLC with multi-wavelength UV detection. Under the optimized conditions, high sensitivity (detection limits 0.1-0.4 ng/mL) and good reproducibility of CPs (RSDs 2.2-7.7% for run-to-run assays) were achieved. Comparative studies showed that graphene was superior to other adsorbents including C18 silica, graphitic carbon, single- and multi-walled carbon nanotubes for the extraction of CPs. Some other advantages of graphene as SPE adsorbent, such as good compatibility with various organic solvents, good reusability and no impact of sorbent drying, have also been demonstrated. The proposed method was successfully applied to the analysis of tap and river water samples with recoveries ranging from 77.2 to 116.6%. This work not only proposes a useful method for environmental water sample pretreatment, but also reveals great potentials of graphene as an excellent sorbent material in analytical processes.
authors.affiliation: State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.
authors.forename: Qian
authors.initials: Q
authors.lastname: Liu
authors.forename: Jianbo
authors.initials: J
authors.lastname: Shi
authors.forename: Lixi
authors.initials: L
authors.lastname: Zeng
authors.forename: Thanh
authors.initials: T
authors.lastname: Wang
authors.forename: Yaqi
authors.initials: Y
authors.lastname: Cai
authors.forename: Guibin
authors.initials: G
authors.lastname: Jiang
mesh_terms: D000327:Adsorption; D002733:Chlorophenols / Q000737:chemistry*; D002851:Chromatography, High Pressure Liquid; D006108:Graphite / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D016014:Linear Models; D018625:Microscopy, Atomic Force; D046529:Microscopy, Electron, Transmission; D037742:Nanotubes, Carbon / Q000737:chemistry; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012822:Silicon Dioxide; D052616:Solid Phase Extraction / Q000379:methods*
chemical_list: D002733:Chlorophenols; D037742:Nanotubes, Carbon; D012822:Silicon Dioxide; D006108:Graphite