Determination of anethole in serum samples by headspace solid-phase microextraction-gas chromatography-mass spectrometry for congener analysis.

A rapid headspace solid-phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS) method has been developed for the determination of anethole in serum samples. Anethole is a characteristic marker for the consumption of aniseed spirits. This method enabled the detection of anethole with a limit of detection (LoD) of 3.6 ng/ml and a limit of quantification (LoQ) of 5.3 ng/ml in serum samples with a good degree of precision intraday (2.8%) and interday (4.5%). Experiments were conducted with one volunteer, in which the subject consumed the alcoholic drink ouzo on 3 different days under controlled conditions. At defined intervals, blood samples were taken from the subject. Using these blood samples, the concentration-time profiles for anethole were determined. In blood samples taken from 50 drivers who claimed to have consumed drinks containing anethole (ouzo, raki and the German aniseed liqueur "Küstennebel") before the taking of the blood sample, anethole was detected in the serum in concentrations of between 5.4 and 17.6 ng/ml in 10 cases. This is the first report describing the qualitative and quantitative determination of a beverage-characteristic aroma compound - in this case anethole - in serum samples after consumption of alcoholic beverages.