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Magnetic nanoparticles (MNPs) with different sizes and characteristics were synthesized to be used as a QuEChERS sorbents for the determination of seven organophosphorus pesticides (OPPs) in strawberries by gas chromatography analysis with flame photometric and mass spectrometry detection. To achieve the optimum conditions of modified QuEChERS procedure several parameters affecting the cleanup efficiency including the amount of the sorbents and cleanup time were investigated. The results were compared with classical QuEChERS methodologies and the modified QuEChERS procedure using MNPs showed the better performance. Under the optimum conditions of the new methodology, three spiking levels (25, 50 and 100 μg kg −1 ) were evaluated in a strawberry sample. The results showed that the average recovery was 93% and the relative standard deviation was less than 12%. The enrichment factor ranged from 111 to 145%. The good linearity with coefficients of determination of 0.9904–0.9991 was obtained over the range of 25–250 μg kg −1 for 7 OPPs. It was determined that the MNPs have an excellent function as sorbent when purified even using less amount of sorbents and the magnetic properties allowed non-use of the centrifugation in cleanup step. The new methodology was applied in strawberry samples from conventional and organic farming. The new sorbents were successfully applied for extraction and determination of OPPs in strawberries. [ABSTRACT FROM AUTHOR]

• New extraction method of xenobiotics from human adipose tissue. • Good sensitivity was achieved by GC-MS and GC-FPD. • The LOD were between 4 to 9 ng/g for synthetic musks • The LOD were between 1 to 7 ng/g for organophosphorus pesticides • Galaxolide was found in all the analyzed human adipose tissue samples. Synthetic musks and organophosphorus pesticides represent a potential risk to the human health since exposure can lead to distinct types of carcinogenesis and endocrine disorders. These are lipophilic compounds as such, prone to deposit and persist in fat tissues, mainly in adipose tissue. Very few studies have reported on the occurrence and accumulation profile of these contaminants in human adipose tissue. Analytical methods for the detection and quantification of synthetic musks and organophosphorus pesticides in adipose tissue are lacking. In this study, the efficacy of different extraction with ultrasonic homogenizer and dispersive solid-phase extraction (d-SPE) clean-up methods were evaluated in human adipose tissue. The relative sample clean-up was assessed by measurement of total lipid content. The quantification of four synthetic musks and six organophosphorus pesticides were performed by gas chromatography (GC) mass spectrometry (MS) and flame photometric detection (FPD), respectively. The d-SPE clean-up with 50 mg PSA, 150 mg MgSO 4 , 100 mg C18EC and 50 mg Z-Sep provided the most effective clean-up, removing the greatest amount of interfering substances including lipids and simultaneously ensuring good chromatographic separation and recoveries. Method detection limits were between 4 to 9 ng/g for synthetic musk and 1 to 7 ng/g for organophosphorus pesticides in adipose tissue. The proposed method was applied to adipose tissue of obese patients and positive samples were confirmed with GC tandem mass spectrometry. Galaxolide was found in all the samples tested with concentrations ranging from 0.08 to 0.5 μg/g of adipose tissue. No other synthetic musk studied was detected. Organophosphorus pesticides were not found in the analysed samples. The developed analytical procedures were successful and can easily be applied to biomonitoring these compounds in human adipose tissue. [ABSTRACT FROM AUTHOR]