Simple SPE–GC method for anethole determination in human serum

Recently, much attention has been given to congener analysis, which can be used to check the possibility of postoffence drinking claims in forensic toxicology. In this type of analysis, the information given by the defendant regarding the type, quantity, and time of consumption of a specific alcoholic beverage is used to calculate theoretically expected congener concentration in the blood and this is compared with the analytically determined concentrations in the blood sample. Many alcoholic drinks aromatized with essential oils of plants and fruits contain a specific congener, for example, anethole in aniseed drinks. The present study describes the GC procedure of anethole analysis in human plasma using SPE as the sample preparation method. The procedure involves the protein precipitation process, which generally degrades the protein–analyte complex, and SPE isolation of anethole from the examined materials. This analytical approach is proposed as a method of choice for the estimation of anethole concentration in human fluids after the consumption of alcoholic beverages and other foods containing the substance. The described method is characterized by a low LOD (8.33 ng/g) and a very high recovery (average recovery 98.37%) of the analyte.