title: Octadecyltrimethoxysilane functionalized ZnO nanorods as a novel coating for solid-phase microextraction with strong hydrophobic surface.
abstract: In this paper, we have, for the first time, proposed an approach by combining self-assembled monolayers (SAMs) and nanomaterials (NMs) for the preparation of novel solid-phase microextraction (SPME) coatings. The self-assembly of octadecyltrimethoxysilane (OTMS) on the surface of ZnO nanorods (ZNRs) was selected as a model system to demonstrate the feasibility of this approach. The functionalization of OTMS on the surface of ZNRs was characterized and confirmed using scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS). The OTMS-ZNRs coated fiber exhibited stronger hydrophobicity after functionalization, and its extraction efficiency for non-polar benzene homologues was increased by a factor of 1.5-3.6 when compared to a ZNRs fiber with almost identical thickness and façade. In contrast, the extraction efficiency of the OTMS-ZNRs coated fiber for polar aldehydes was 1.6-4.0-fold lower than that of the ZNRs coated fiber, further indicating its enhanced surface hydrophobicity. The OTMS-ZNRs coated fiber revealed a much higher capacity upon increasing the OTMS layer thickness to 5 μm, leading to a factor of 12.0-13.4 and 1.8-2.5 increase in extraction efficiency for the benzene homologues relative to a ZNRs coated fiber and a commercial PDMS fiber, respectively. The developed HS-SPME-GC method using the OTMS-ZNRs coated fiber was successfully applied to the determination of the benzene homologues in limnetic water samples with recovery ranging from 83 to 113% and relative standard deviations (RSDs) of less than 8%.
authors.affiliation: State key laboratory of heavy oil processing, College of Science, China University of Petroleum, Qingdao, China.
authors.forename: Jingbin
authors.initials: J
authors.lastname: Zeng
authors.forename: Haihong
authors.initials: H
authors.lastname: Liu
authors.forename: Jinmei
authors.initials: J
authors.lastname: Chen
authors.forename: Jianli
authors.initials: J
authors.lastname: Huang
authors.forename: Jianfeng
authors.initials: J
authors.lastname: Yu
authors.forename: Yiru
authors.initials: Y
authors.lastname: Wang
authors.forename: Xi
authors.initials: X
authors.lastname: Chen
mesh_terms: D001554:Benzene / Q000032:analysis*; D057927:Hydrophobic and Hydrophilic Interactions; D008855:Microscopy, Electron, Scanning; D043942:Nanotubes; D012821:Silanes; D052617:Solid Phase Microextraction / Q000379:methods*; D013052:Spectrometry, X-Ray Emission; D014874:Water Pollutants, Chemical / Q000032:analysis*; D015034:Zinc Oxide
chemical_list: D012821:Silanes; D014874:Water Pollutants, Chemical; C024779:octadecylsilane; D001554:Benzene; D015034:Zinc Oxide