| abstract |
The subject invention concerns zirconia-based hybrid organic-inorganic sol-gel coating for optional use as a stationary phase in capillary microextraction (CME), gas chromatographic (GC), high performance liquid chromatography (HPLC), capillary electrophoresis (CE), capillary electrochromatography (CEC) and related analytical techniques. Sol-gel chemistry is employed to chemically bind a hydroxy-terminated silicone polymer (polydimethyldiphenylsiloxane, PDMDPS) to a sol-gel zirconia network. In one embodiment, a fused silica capillary is filled with a properly designed sol solution to allow for the sol-gel reactions to take place within the capillary. In the course of this process, a layer of the evolving hybrid organic-inorganic sol-gel polymer becomes chemically bonded to the silanol groups on the inner capillary walls. The unbonded part of the sol solution is expelled from the capillary under helium pressure, leaving behind a chemically bonded sol-gel zirconia-PDMDPS coating on the inner walls of the capillary. Polycyclic aromatic hydrocarbons, ketones, and aldehydes are efficiently extracted and preconcentrated from dilute aqueous samples followed by GC separation of the extracted analytes. |