Determination of thymol in human plasma by automated headspace solid-phase microextraction-gas chromatographic analysis.

A reliable and sensitive method was developed for determination of thymol in human plasma by automated headspace solid-phase microextraction (SPME). After enzymatic cleavage of thymol sulfate thymol was extracted by a 65 microm polydimethylsiloxane-divinylbenzene crimped fiber (Supelco) after addition of sodium chloride and phosphoric acid (85%). Desorption of the fiber was performed in the injection port of a gas chromatograph at 220 degrees C (HP 5890; 50 m x 0.