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This paper describes a procedure for the isolation of 20 organic micro-pollutants among pesticides, drugs, recreational drugs, flame retardants from river sediments. After a solid-liquid extraction with a methanol:water (50:50, v/v) solution, the supernatant was diluted with water and cleaned up by stir-disc solid-phase extraction (SPE). The disc was made of buckypaper, a self-supporting entangled assembly of carbon nanotubes, which was used as a highly porous, two-sided, sorbent membrane. In the preliminary activation step, the membrane was oxidised for 2-hours with nitric acid to extend its extraction capability also to more polar compounds. All extracts were analysed by ultra-high-performance liquid chromatography-tandem mass spectrometry. A comparative investigation with commercial Strata-X Polymeric Reversed Phase SPE cartridges proved the effectiveness of the lab-made device. On the average, the analytes were recovered with yields around 69% (low spike level) and 80% (medium and high spike level), while only a couple of analytes exhibited values less than 50%. The relative standard deviation was always less than 20%. Limits of detections were in the range 0.02-9.9 ng g -1 . The validated method was then applied for the analysis of sediment samples from different sites of the River Turia basin in the area of Valencia (Spain), finding tris(2-chloroisopropyl)-phosphate in all sediments at a level ranging from 6.9 to 387.9 ng g -1 . Other compounds, such as pesticides and pharmaceuticals were more sporadically in these samples., Competing Interests: Declaration of Competing Interest Regarding the manuscript entitled “Multi-residue determination of organic micro-pollutants in river sediment by stir-disc solid phase extraction based on oxidized buckypaper” by P. Tomai, A. Gentili, S. Fanali, Yolanda Picó, the authors certify that there is no conflict of interest including any financial, personal or other relationships with other people or organizations regarding the material discussed., (Copyright © 2020. Published by Elsevier B.V.)

This article discusses research on strong coupling between the mechanical and electronic properties of a carbon nanotube. It references two studies published in "Science," one by Adrian Bachtold and colleagues at the CIN2 laboratory in Barcelona and Chalmers University of Technology in Spain, and another by Gary Steele and colleagues at the Delft University of Technology in Sweden. The two groups of researchers study nanotubes that have been suspended between the source and drain electrodes, with a gate electrode nearby.

This section offers news briefs on nanotechnology research. U.S. researchers have managed to isolate and crystallize a gold-thiolate cluster, which allowed them to determine the X-ray structure of gold nanoparticles. Scientists in Australia have studied the behavior of zinc oxide nanoparticles in freshwater systems to better understand their potential toxicity. Researchers in Spain have used a carbon nanotube to build a transistor that detects single electrons.

A method was developed for the simultaneous detection of eight polyphenols (t-resveratrol, (+)-catechin, quercetin and p-coumaric, caffeic, sinapic, ferulic, and gallic acids) by CZE with electrochemical detection. Separation of these polyphenols was achieved within 25 min using a 200 mM borate buffer (pH 9.4) containing 10% methanol as separation electrolyte. Amperometric detection of polyphenols was carried out with a glassy carbon electrode (GCE) modified with a multiwalled carbon nanotubes (CNT) layer obtained from a dispersion of CNT in polyethylenimine. The excellent electrochemical properties of this modified electrode allowed the detection and quantification of the selected polyphenols in white wines without any pretreatment step, showing remarkable signal stability despite the presence of potential fouling substances in wine. The electrophoretic profiles of white wines, obtained using this methodology, have proven to be useful for the classification of these wines by means of chemometric multivariate techniques. Principal component analysis and discriminant analysis allowed accurate classification of wine samples on the basis of their grape varietal (verdejo and airén) using the information contained in selected zones of the electropherogram. The utility of the proposed CZE methodology based on the electrochemical response of CNT-modified electrodes appears to be promising in the field of wine industry and it is expected to be successfully extended to classification of a wider range of wines made of other grape varietals., (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)