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A novel solid phase microextraction Arrow (SPME Arrow) system has been applied for the first time to determine synthetic musk fragrances in fish samples. The lack of regulation concerning the concentration of musk fragrances in fish along with the risk associated to these compounds has led to an increased development of analytical methods on this topic. This study applies SPME Arrow followed by gas chromatography coupled to tandem mass spectrometry (ion trap) to determine nine musk fragrances and compares this novel technique with its predecessor (SPME). Parameters such as type of coating, extraction time and temperature as well as water addition were optimized to achieve higher sensitivity. Results show that detection limits ranging between 0.5 ng g -1 (for cashmeran, celestolide, phantolide, tonalide and musk ketone) and 2.5 ng g -1 (dry weight) (for musk xylene) when SPME Arrow is used instead of a conventional fibre, with an up to ten-fold increase in sensitivity. Moreover, commercial fish samples were analysed using the method developed and galaxolideand tonalidewere quantified at concentrations ranging from 6.5 ng g -1 to 17.5 ng g -1 (d.w.) and 2.9 ng g -1 and 5.1 ng g -1 (d.w.) in all the species analysed., (Copyright © 2019 Elsevier B.V. All rights reserved.)

A new method is introduced for the sampling of volatile low molecular weight alkylamines in ambient air and wastewater by utilizing a novel SPME Arrow system, which contains a larger volume of sorbent compared to a standard SPME fiber. Parameters affecting the extraction, such as coating material, need for preconcentration, sample volume, pH, stirring rate, salt addition, extraction time and temperature were carefully optimized. In addition, analysis conditions, including desorption temperature and time as well as gas chromatographic parameters, were optimized. Compared to conventional SPME fiber, the SPME Arrow had better robustness and sensitivity. Average intermediate reproducibility of the method expressed as relative standard deviation was 12% for dimethylamine and 14% for trimethylamine, and their limit of quantification 10μg/L and 0.13μg/L respectively. Working range was from limits of quantification to 500μg/L for dimethylamine and to 130μg/L for trimethylamine. Several alkylamines were qualitatively analyzed in real samples, while target compounds dimethyl- and trimethylamines were quantified. The concentrations in influent and effluent wastewater samples were almost the same (∼80μg/L for dimethylamine, 120μg/L for trimethylamine) meaning that amines pass the water purification process unchanged or they are produced at the same rate as they are removed. For the air samples, preconcentration with phosphoric acid coated denuder was required and the concentration of trimethylamine was found to be around 1ng/m(3). The developed method was compared with optimized method based on conventional SPME and advantages and disadvantages of both approaches are discussed., (Copyright © 2015 Elsevier B.V. All rights reserved.)

In-tube extraction (ITEX) is a novel solventless extraction technique in which a headspace syringe with a needle body filled with a sorbent (here: Tenax TA) is used. The analytes are extracted from sample headspace by dynamic extraction. The needle body is surrounded by a separate heater, which is used for thermal desorption of analytes into the injection port of a GC system. We report here for the first time the optimization and evaluation of a fully automated analytical method based on ITEX. As target analytes, 19 common groundwater contaminants such as halogenated volatiles and monoaromatic compounds have been chosen. Method related parameters such as extraction temperature, number of extraction cycles, extraction and desorption volume as well as extraction and desorption flow rates were investigated in detail. The linear dynamic range of the ITEX method ranged over six orders of magnitude between 0.028 microg/L and 1218 microg/L with linear correlation coefficients between 0.990 and 0.998 for the investigated compounds. Method detection limits for monoaromatic compounds were between 28 ng/L (ethylbenzene) and 68 ng/L (1,2,4-trimethylbenzene). For halogenated volatile organic compounds, method detection limits between 48 ng/L (chloroform) and 799 ng/L (dichloromethane) were obtained. The precision of the method with external calibration was between 3.1% (chloroform ethylbenzene) and 7.4% (1,2,3-trimethylbenzene).