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PubMed · 15881453

Highly porous solid-phase microextraction fiber coating based on poly(ethylene glycol)-modified ormosils synthesized by sol-gel technology.

Raquel Gomes da Costa Silva·Fabio Augusto
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Abstract

The preparation and characteristics of solid-phase microextraction (SPME) fibers coated with Carbowax 20M ormosil (organically modified silica) are described here. Raw fused silica fibers were coated with Carbowax 20M-modified silica using sol-gel process. Scanning electron micrographs of fibers revealed a highly porous, sponge-like coating with an average thickness of (8 +/- 1) microm. The sol-gel Carbowax fibers were compared to commercial fibers coated with 100 microm polydimethylsiloxane (PDMS) and 65 microm Carbowax-divinylbenzene (DVB). Shorter equilibrium times were possible with the sol-gel Carbowax fiber: for headspace extraction of the test analytes, they ranged from less than 3 min for benzene to 15 min for o-xylene. Extraction efficiencies of the sol-gel Carbowax fiber were superior to those of conventional fibers: for o-xylene, the extracted masses were 230 and 540% of that obtained with 100 microm PDMS and 65 microm Carbowax-DVB fibers, respectively.

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BenzeneBenzene DerivativesChromatography, High Pressure LiquidDimethylpolysiloxanesFiber Optic TechnologyGelsMicrochemistryMicroscopy, Electron, ScanningPhase TransitionPolyethylene GlycolsSiliconesTolueneVinyl CompoundsComparative StudyJournal ArticleResearch Support, Non-U.S. Gov't

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Raquel Gomes da Costa Silva, Fabio Augusto. 2005-04-22. Highly porous solid-phase microextraction fiber coating based on poly(ethylene glycol)-modified ormosils synthesized by sol-gel technology.. https://doi.org/10.1016/j.chroma.2004.11.027

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