Development of a programmed temperature vaporization-gas chromatography-tandem mass spectrometry method for polycyclic aromatic hydrocarbons analysis in biota samples at ultratrace levels.

This paper presents the development of a programmed temperature vaporization-gas chromatography-tandem mass spectrometry (PTV-GC-MS-MS) method for the determination of PAHs in complex environmental matrices. This method aims at overcoming the current problems in detecting these compounds in matrices such as biota samples. When these matrices are extracted, great amounts of lipid compounds are co-extracted and can interfere with the analysis of PAHs, complicating their identification and quantification. The developed method significantly improves the detection and quantification limits, since PTV-GC-MS-MS can detect compounds at low-ppb level in complex matrices. The instrumental LODs and LOQs achieved lie between 1.04 and 26.9ngl(-1) and 2.06 and 45.4ngl(-1), respectively, and are lower than those calculated in the GC-MS-SIM mode. The LODs and LOQs of the method range between 1.9 and 3.6ngkg(-1) and between 79 and 99ngkg(-1), respectively. The validation of the method were made with a mussel reference material (SRM 2799). The applicability of the method to real mussel samples was also studied. Samples were extracted by means of microwave energy (with acetone:hexane 1:1, v/v) and the extracts were cleaned in a glass column with 22g of alumina. The usefulness of the MS-MS detection was verified. The obtained results were satisfactory, with good accuracy and precision. The proposed PTV-GC-MS-MS method was successfully applied to real mussel samples affected by the Prestige sinking off the Galician coast.