title: Preparation of graphene-coated solid-phase microextraction fiber and its application on organochlorine pesticides determination.
abstract: The coating material determines the sensitivity and selectivity of solid-phase microextraction (SPME). Graphene is predicted to have remarkable properties, such as high thermal conductivity, superior mechanical properties, excellent electronic transport properties and good extraction ability. In this work we immobilized the graphene onto a stainless steel wire to obtain a novel SPME coating based on sol-gel technique. The new fiber possessed a homogeneous, porous surface and showed excellent thermal and solvent stability. Under the optimized conditions, its extraction efficiencies for seven organochlorine pesticides (OCPs) were higher than those of two commercial fibers (PDMS, 85μm; PDMS/DVB, 65μm). Using the self-made sol-gel-graphene SPME fiber, the limits of detections for seven OCPs were found to be ranged from 0.19ngL(-1) (o,p-DDT) to 18.3ngL(-1) (heptachlor). The repeatabilities for each single fiber were evaluated and the relative standard deviations (RSDs) ranged from 4.7% to 10.6%. The reproducibilities of fiber-to-fiber were 2.3-13.6%. The developed method was successfully applied to the determination of OCPs in rainwater. Hexachlorobenzene (62.7ng/L), trans-chlordance (79.6ng/L) and p,p-DDT (9.30ng/L) were detected. The relative recoveries ranged from 77.7% to 120%.
authors.affiliation: State Key Laboratory Breeding Base of Eco-Environments and Bio-Resources of the Three Gorges Reservoir Region/MOE Key Laboratory of Aquatic Product Safety/KLGHEI of Environment and Energy Chemistry, School of Chemistry and Chemical Engineering, Sun Yat-sen University, Guangzhou 510275, China.
authors.forename: Yuanyuan
authors.initials: Y
authors.lastname: Ke
authors.forename: Fang
authors.initials: F
authors.lastname: Zhu
authors.forename: Feng
authors.initials: F
authors.lastname: Zeng
authors.forename: Tiangang
authors.initials: T
authors.lastname: Luan
authors.forename: Chengyong
authors.initials: C
authors.lastname: Su
authors.forename: Gangfeng
authors.initials: G
authors.lastname: Ouyang
mesh_terms: D002849:Chromatography, Gas / Q000379:methods; D006108:Graphite / Q000737:chemistry*; D006843:Hydrocarbons, Chlorinated / Q000032:analysis* / Q000302:isolation & purification; D057230:Limit of Detection; D016014:Linear Models; D010575:Pesticides / Q000032:analysis* / Q000302:isolation & purification; D044367:Phase Transition; D015203:Reproducibility of Results; D052617:Solid Phase Microextraction / Q000295:instrumentation / Q000379:methods*; D014874:Water Pollutants, Chemical / Q000032:analysis / Q000302:isolation & purification
chemical_list: D006843:Hydrocarbons, Chlorinated; D010575:Pesticides; D014874:Water Pollutants, Chemical; D006108:Graphite