title: Monolithic graphene fibers for solid-phase microextraction.
abstract: Monolithic graphene fibers for solid-phase microextraction (SPME) were fabricated through a dimensionally confined hydrothermal strategy and their extraction performance was evaluated. For the fiber fabrication, a glass pipeline was innovatively used as a hydrothermal reactor instead of a Teflon-lined autoclave. Compared with conventional methods for SPME fibers, the proposed strategy can fabricate a uniform graphene fiber as long as several meters or more at a time. Coupled to capillary gas chromatography (GC), the monolithic graphene fibers in a direct-immersion (DI) mode achieved higher extraction efficiencies for aromatics than those for n-alkanes, especially for polycyclic aromatic hydrocarbons (PAHs), thanks to π-π stacking interaction and hydrophobic effect. Additionally, the fibers exhibited excellent durability and can be repetitively used more than 160 times without significant loss of extraction performance. As a result, an optimum extraction condition of 40°C for 50min with 20% NaCl (w/w) was finally used for SPME of PAHs in aqueous samples. For the determination of PAHs in water samples, the proposed DI-SPME-GC method exhibited linear range of 0.05-200μg/L, limits of detection (LOD) of 4.0-50ng/L, relative standard deviation (RSD) less than 9.4% and 12.1% for one fiber and different fibers, respectively, and recoveries of 78.9-115.9%. The proposed method can be used for analysis of PAHs in environmental water samples.
authors.affiliation: Key Laboratory of Cluster Science, Ministry of Education of China, and School of Chemistry, Beijing Institute of Technology, Beijing 100081, PR China.
authors.forename: Jing
authors.initials: J
authors.lastname: Fan
authors.forename: Zelin
authors.initials: Z
authors.lastname: Dong
authors.forename: Meiling
authors.initials: M
authors.lastname: Qi
authors.forename: Ruonong
authors.initials: R
authors.lastname: Fu
authors.forename: Liangti
authors.initials: L
authors.lastname: Qu
mesh_terms: D006108:Graphite / Q000737:chemistry*; D006358:Hot Temperature; D008855:Microscopy, Electron, Scanning; D011084:Polycyclic Aromatic Hydrocarbons / Q000302:isolation & purification; D052617:Solid Phase Microextraction / Q000295:instrumentation*; D014867:Water
chemical_list: D011084:Polycyclic Aromatic Hydrocarbons; D014867:Water; D006108:Graphite
keywords: Capillary gas chromatography; Monolithic graphene fiber; Polycyclic aromatic hydrocarbons; Solid-phase microextraction