Artículos de revistas
Highly Porous Solid-phase Microextraction Fiber Coating Based On Poly(ethylene Glycol)-modified Ormosils Synthesized By Sol-gel Technology.
Registro en:
Journal Of Chromatography. A. v. 1072, n. 1, p. 7-12, 2005-Apr.
0021-9673
15881453
Autor
da Costa Silva, Raquel Gomes
Augusto, Fabio
Institución
Resumen
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. 1072 7-12