Gas chromatographic determination of thymol.

Thymol in biological samples is analyzed by gas chromatography utilizing a 5% OV-25 column, a flame ionization detector, and eugenol as an internal standard. Samples are extracted with diethyl ether and analyzed without derivatization. The lower limit of detection of thymol in a sample is about 0.01 μg and quantitation is satisfactory in plasma at $\text{0.05 μ}\text{g}\text{2}\text{ml}$. Data was recorded digitally on magnetic tape and calculated off-line at a central facility.