Stability of amphiphilic and hydrophobic pollutants in nanostructured liquids based on anionic micelles

II Encuentro sobre nanociencia y nanotecnología de investigadores y tecnólogos de la Universidad de Córdoba. NANOUC

Identification of bisphenols and derivatives in greenhouse dust as a potential source for human occupational exposure

Bisphenol A (BPA) and alternative bisphenols are widely used in the industrial production of polycarbonates and resin polymers. Adverse effects on human health have been described for BPA and owing to the structural similarity of alternative bisphenols and derivatives, a similar toxicity profile is expectable. Dust can act as a sink for bisphenols owing to the large surface area to mass ratio. Human risk exposure to bisphenols via indoor dust has been widely assessed in the last decade. The environmental conditions inside greenhouses, among other factors, facilitate that chemicals are released from greenhouse building materials to dust. This study aims to explore for the first time the potential of greenhouse dust as a new source of bisphenols for human exposure. For this purpose, a supramolecular solvent-based method was applied to the extraction of twenty-one bisphenols from greenhouse dust, prior to their determination by liquid chromatography–tandem mass spectrometry. Nineteen bisphenols were found in the five greenhouse dust samples analysed, with concentrations ranging from 5275 ng g(−1) (BPA) to 0.25 ng g(−1) (trichlorobisphenol A). The average daily dose (ADD) via dust ingestion for bisphenol compounds was calculated, in order to estimate the occupational exposure for inadvertent dust ingestion. Despite the calculated ADD value for BPA (47.81 ng kg(−1) day(−1)) being below the tolerable daily intake proposed by EFSA (4·10(3) ng kg(−1) day(−1)), this value was considerably higher than those previously reported for indoor dust, which brings to light the importance of considering greenhouse dust as bisphenols source of exposure for greenhouse workers. GRAPHICAL ABSTRACT: [Image: see text

Análisis de compuestos perfluorados en suero sanguíneo mediante microextracción con disolventes supramoleculares y cromatografía líquida/espectrometría de masas con trampa iónica

III Encuentro sobre Nanociencia y Nanotecnología de Investigadores y Tecnólogos Andaluce

MIcroextracción supramolecular de ocratoxina A (OTA) en pasas previa a su determinación por cromatografía/fluorescencia

III Encuentro sobre Nanociencia y Nanotecnología de Investigadores y Tecnólogos Andaluce

The interaction of carbon nanotubes with an invitro blood-brain barrier model and mouse brain in vivo

Under a Creative Commons license.-- et al.Carbon nanotubes (CNTs) are a novel nanocarriers with interesting physical and chemical properties. Here we investigate the ability of amino-functionalized multi-walled carbon nanotubes (MWNTs-NH3+) to cross the Blood-Brain Barrier (BBB) in vitro using a co-culture BBB model comprising primary porcine brain endothelial cells (PBEC) and primary rat astrocytes, and in vivo following a systemic administration of radiolabelled f-MWNTs. Transmission Electron microscopy (TEM) confirmed that MWNTs-NH3+ crossed the PBEC monolayer via energy-dependent transcytosis. MWNTs-NH3+ were observed within endocytic vesicles and multi-vesicular bodies after 4 and 24 h. A complete crossing of the in vitro BBB model was observed after 48 h, which was further confirmed by the presence of MWNTs-NH3+ within the astrocytes. MWNT-NH3+ that crossed the PBEC layer was quantitatively assessed using radioactive tracers. A maximum transport of 13.0 ± 1.1% after 72 h was achieved using the co-culture model. f-MWNT exhibited significant brain uptake (1.1 ± 0.3% injected dose/g) at 5 min after intravenous injection in mice, after whole body perfusion with heparinized saline. Capillary depletion confirmed presence of f-MWNT in both brain capillaries and parenchyma fractions. These results could pave the way for use of CNTs as nanocarriers for delivery of drugs and biologics to the brain, after systemic administration.KAJ acknowledges funding from Biotechnology and Biological Sciences Research Council (BB/J008656/1) and Worldwide Cancer Research (12-1054). KAJ, EP and BB acknowledge the EU FP7-ITN Marie-Curie Network programme RADDEL (290023). HK was sponsored by the Atomic Energy Commission of Syria. EP is enrolled in the UAB PhD program. KAJ thanks the members of the EU COST actions TD1004 (Theranostics Imaging and Therapy: An Action to Develop Novel Nanosized Systems for Imaging-Guided Drug Delivery and Biological Processes) for sponsoring HK's research stay at the ICN2 for the electron microscopy studies. ICN2 acknowledges support from the Severo Ochoa Program (MINECO, Grant SEV-2013-0295). Open Access funded by Biotechnology and Biological Sciences Research CouncilPeer Reviewe

Optimization Problems in Spanish Differential Calculus Books Published in the 18th Century

History of mathematics and mathematics education research allows us to know, among other issues: the influence that certain textbooks have had on the teaching of school mathematics, in academic or professional training, during a certain historical period; as well as the scientific advances achieved in each historical period and their incorporation into the teaching of the subject matter. In this work, we focus our attention on the applications of the method of finding maxima and minima included in the textbooks published during the 18th century in Spain. Specifically, we identify the approach of the algorithm used, the shortcomings or deficiencies that the posing of the proposed problems may have, the verification of the nature of the optimal points obtained and the consideration—or not—of the negative solutions in the process of resolution