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Many dietary supplements claim the ability to enhance sports performance and to improve the fitness of the consumers. Occasionally, along with legal ingredients, illicit compounds may be added without being labelled, leading to unintended doping. Hence, the aim of this study was to develop an analytical method to determine a set of 12 polar (logDpH=7 from −2.0 to +0.3) compounds including diuretics, stimulants, β2-agonists, methylxanthines, and sweeteners. Hydrophilic interaction liquid chromatography was chosen as separation strategy, coupled with tandem mass spectrometry. The instrumental method was optimized using a two-step design of experiments (DoE). Firstly, a Plackett–Burman (PB) DoE was performed to identify the more influencing variables affecting peak areas and chromatographic resolution among temperature, water percentage in the mobile phase, and flow rate, as well as type and concentration of buffers. Secondly, a D-optimal DoE was set, considering only the most significant variables from the PB-DoE results, achieving a deeper understanding of the retention mechanism. Sample processing by salt-assisted liquid–liquid extraction was studied through DoE as well, and the whole method showed recoveries in the range 40–107% and procedural precision ≤11% for all analytes. Finally, it was applied to real samples, in which the four methylxanthines and two artificial sweeteners were detected and quantified in the range of 0.02–192 mg g−1. These values were compared to the quantities declared on the DS labels, when possible. Furthermore, a sequence of MS/MS scans allowed detection of a signal in one of the samples, structurally similar to the β2-agonist clenbuterol. [ABSTRACT FROM AUTHOR]

Within the world of natural food supplements, organic extracts deriving from young plant meristematic tissue (bud-derivatives) are becoming attractive, thanks to their richness in bioactive molecules. This natural source is scarce, but every year, tons of plant material, including buds, come from city pruning. If this sustainable source is rather promising from a circular economy point of view, the safety of the obtained supplements must be assessed. In fact, anthropic microcontaminants, such as polycyclic aromatic hydrocarbons (PAHs), could adsorb onto the urban buds, leading to a possible contamination of the bud-derivatives. In this study, we developed a magnetic dispersive solid phase extraction (m-dSPE) based on molecularly imprinted microparticles, combined with GC-MS, to quantify the 16 priority PAHs in such extracts. The D-optimal experimental design was implemented to maximize analytes' recovery with the smallest set of experiments. The optimized method was characterized by great selectivity thanks to the molecular imprinted polymer and ease of use provided by m-dSPE. Moreover, it complies with green principles, thanks to the minimum consumption of organic solvent (1.5 mL of acetone per sample). The recoveries ranged from 76 to 100% and procedural precision was below 10% for most PAHs. Despite the matrix complexity, low quantification limits (0.7–12.6 μg kg−1) were reached. This guaranteed the PAHs' quantitation at levels below those indicated as safe by a European Community regulation on food supplements. None of the analyzed samples, coming from different anthropically impacted areas, showed concerning PAHs levels. [ABSTRACT FROM AUTHOR]

Polar organic chemical integrative samplers (POCIS) are widely used in their standard configuration for sampling contaminants in water bodies. A wider polyethersulfone (PES) membrane pore size was employed in POCIS exposed in a static calibration experiment to investigate the uptake of 21 emerging contaminants ranging from hydrophilic (perfluoroalkyl compounds, xanthines, an artificial sweetener) to more hydrophobic compounds (pharmaceuticals, oestrogens, UV filters). Compared to standard POCIS with 0.1-µm pore size PES membranes, the POCIS with 5-µm pore size PES membranes did not increase sampling rates for compounds of relatively low and mid-hydrophobicity. However, the uptake of more hydrophobic and anionic compounds, which either poorly diffuse through or are retained within the standard 0.1-µm PES membrane, showed a marked increase. This led to the first ever recorded sampling rates for triclosan (0.249 L day−1) and two UV filters (0.075–0.123 L day−1). Based on these results, more attention should be placed on the choice of the appropriate membrane for each POCIS application. The most suitable configuration depends on the studied compound physico-chemical characteristics—such as the polarity and the compound membrane-to-sorbent partitioning coefficient—but also on the site conditions (deployment time, fouling, flow variations, et.). [ABSTRACT FROM AUTHOR]

To provide a new insight into the response of plants to abiotic stresses, the ionomic profiles of Nicotiana langsdorffii specimens have been determined before and after exposure to toxic metals (chromium) or drought conditions. The plants were genetically transformed with the rat glucocorticoid receptor (GR) or the gene for Agrobacterium rhizogenes rolC, because these modifications are known to produce an imbalance in phytohormone equilibria and a significant change in the defence response of the plant. Elemental profiles were obtained by developing and applying analytical procedures based on inductively coupled plasma atomic emission and mass spectrometry (ICP-AES/MS). In particular, the removal of isobaric interferences affecting the determination of Cr and V by ICP-MS was accomplished by use of a dynamic reaction cell, after optimization of the relevant conditions. The combined use of ICP atomic emission and mass spectrometry enabled the determination of 29 major and trace elements (Ba, Bi, Ca, Cd, Co, Cr, Cu, Eu, Fe, Ga, K, Li, Mg, Mn, Mo, Na, P, Pb, Pt, Rb, S, Sb, Sn, Sr, Te, V, W, Y, and Zn) in different parts of the plants (roots, stems, and leaves), with high accuracy and precision. Multivariate data processing and study of element distribution patterns provided new information about the ionomic response of the target organism to chemical treatment or water stress. Genetic modification mainly affected the distribution of Bi, Cr, Mo, Na, and S, indicating that these elements were involved in biochemical processes controlled by the GR or rolC genes. Chemical stress strongly affected accumulation of several elements (Ba, Ca, Fe, Ga, K, Li, Mn, Mo, Na, P, Pb, Rb, S, Sn, Te, V, and Zn) in different ways; for Ca, Fe, K, Mn, Na, and P the effect was quite similar to that observed in other studies after treatment with other transition elements, for example Cu and Cd. The effect of water deficit was less evident, mainly consisting in a decrease of Ba, Cr, Na, and Sr in roots. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

In the context of the entire analytical process, pre-treatment of soil samples is often inadequately considered although the reliability of the results is definitely compromised if the sample is not properly prepared. In this paper, the effect of drying conditions in soil sample pre-treatment on the determination of polycyclic aromatic hydrocarbons (PAHs) has been studied. A systematic approach has been adopted by varying soil type, drying temperatures and solvent polarity to highlight the effect on the analyte recovery; the relationship between PAH molecular structure and their evaporation process from soils is discussed. Experimental data demonstrate that, concerning temperature-assisted drying procedures, PAHs are divided in two distinct groups: PAHs lighter than pyrene, which are seriously affected by drying temperature; and heavier PAHs that can be considered as non-volatile compounds. For studies involving the analysis of lighter PAHs in environmental samples, working on as-received samples is necessary. [ABSTRACT FROM AUTHOR]

A simple, selective and highly sensitive method was developed and optimized to determine the most commonly used UV filters with endocrine-disrupting potential in water, namely benzophenone-3 (BP-3), octocrylene (OC), ethylhexyl dimethyl p-aminobenzoate (OD-PABA), ethylhexyl methoxycinnamate, ethylhexyl salicylate (EHS) and homosalate (HMS). Samples were extracted by stir bar sorptive extraction followed by liquid desorption (SBSE-LD). The important factors influencing SBSE-LD were optimized. Under optimal conditions, assays were performed on 50 mL of water sample using stir bars (0.5 mm in film thickness, 10 mm in length) at room temperature. The analytes were determined by liquid chromatography-tandem mass spectrometry with triple quadrupole analyzer using atmospheric pressure chemical ionization. The main parameters in HPLC-APCI-MS/MS were also optimized to provide the best performances for all analytes. Moreover, matrix effect was investigated using two methods the post-column infusion system and the method of spiked matrices after extraction. As a result, no significant matrix effect on the analysis was observed. The method showed good linearity ( R coefficients greater than 0.996 in different water samples after SBSE-LD). Recoveries of the analytes were close to 90%, except for BP-3 (64%) and OC (76%) with relative standard deviation lower than 11%. Detection limits were between 0.6 and 3.3 ng L for all the analytes except for HMS (94 ng L) and EHS (114 ng L). This methodology was applied to measure UV filters in seawater, river water and wastewater in different sites of Liguria; BP-3 and OC were found in most of the considered samples at rather low concentration level. [ABSTRACT FROM AUTHOR]

fast liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS-MS) method was developed to study five endocrine-disrupting compounds (4- n-nonylphenol, bisphenol A, estrone, 17β-estradiol and 17α-ethinylestradiol) in water. Different columns were tested; the chromatographic separation of the analytes was optimized on a Pinnacle DB biphenylic column with a water–acetonitrile gradient elution, which allowed the separation of the selected endocrine-disrupting compounds (EDCs) in less than 6 min. Quantitative analysis was performed in selected reaction monitoring (SRM) mode; two transitions were chosen for each compound, using the most abundant for quantitation. Calibration curves using bisphenol A- d as internal standard were drawn, showing good correlation coefficients (0.9993–0.9998). All figures of merit of the method were satisfactory; limits of detection were in the low pg range for all analytes. The method was then applied to the determination of the analytes in real water samples: to this aim, polar organic chemical integrative samplers (POCIS) were deployed in the influent and in the effluent of a drinking water treatment plant in Liguria (Italy). The EDC level was rather low in the influent and negligible in the outlet, reflecting the expected function of the treatment plant. [ABSTRACT FROM AUTHOR]

A new method using the extraction and preconcentration capabilities of stir bar sorptive extraction, combined with high-resolution gas chromatography and mass spectrometry, was developed for the determination of five selected endocrine-disrupting compounds (4- n-nonylphenol, bisphenol A, estrone, 17β-estradiol, and 17α-ethinylestradiol) in water. In situ derivatization to transform the phenolic compounds into lipophilic and volatile analytes was carried out with acetic anhydride. Two different methods of headspace derivatization to further improve the chromatographic properties of 17β-estradiol and 17α-ethinylestradiol were developed and compared. The optimized method provided good sensitivity (limits of quantitation 1.2–2.6 ng), repeatability (relative standard deviation 2–9%), and reproducibility (relative standard deviation 10–17%). Passive sampling by means of polar organic chemical integrative samplers was applied to monitor river waters used as supply sources for drinking water treatment plants in the Liguria region of Italy. The analytes showed a different distribution at the three sites considered; bisphenol A proved to be the most abundant, ranging from 185 to 459 ng per sampler. [ABSTRACT FROM AUTHOR]

An interdisciplinary approach was employed to monitor the concentration and the effects of butyltin compounds in mussels ( Mytilus galloprovincialis). Tissues from animals exposed to a marine area (Vado Ligure harbour) with a high concentration of tributyltin (TBT) were analysed and compared with control samples. TBT concentrations were measured by gas chromatography–mass spectrometry and the protein pattern in gill tissues was studied by proteomic analysis. Several proteomic signatures associated with contaminant exposure were observed; spots that were significantly increased in all contaminated samples were identified by mass spectrometry as fragments of β-tubulin. The degradation of β-tubulin was then confirmed by western blot analysis with specific anti-β-tubulin antibody. The effects observed on mussel gills after exposure in the TBT-polluted area are discussed. [ABSTRACT FROM AUTHOR]