Technetium (Tc) is an environmentally relevant radioactive contaminant whose migration is limited when Tc(VII) is reduced to Tc(IV). However, its reaction mechanisms are not well understood yet. We have combined electrochemistry, spectroscopy, and microscopy (cyclic voltammetry, rotating disk electrode, X-ray photoelectron spectroscopy, and Raman and scanning electron microscopy) to study Tc(VII) reduction in non-complexing media: 0.
View Article and Find Full Text PDFReductive immobilization of Tc by a synthetic FeS mixture, i.e. marcasite-pyrite 60:40, was studied by a combined approach of batch experiments and powder X-ray diffraction, X-ray photoelectron spectroscopy as well as Raman microscopy.
View Article and Find Full Text PDFTechnetium (Tc) retention on gamma alumina nanoparticles (γ-AlO NPs) has been studied in the absence (binary system) and presence (ternary system) of previously sorbed Fe as a reducing agent. In the binary system, γ-AlO NPs sorb up to 6.5% of Tc from solution as Tc(VII).
View Article and Find Full Text PDFTc(VII) uptake by synthetic pure pyrite at 21 °C was studied in a wide pH range from 3.50 to 10.50 using batch experiments combined with scanning electron microscopy, X-ray absorption spectroscopy (XAS), X-ray photoelectron spectroscopy (XPS), and Raman microscopy.
View Article and Find Full Text PDFThe side chain effect on transport in ionic aqueous salt solutions was investigated for [Formula: see text]-amino acids glycine, alanine, [Formula: see text]-amino butyric acid, norvaline, and norleucine --that together define a chemical homologous series based on the length of the characteristic side chain which increases from zero to four carbons, respectively. Binary mutual diffusion coefficients at infinitesimal concentration in aqueous solutions of NaCl (0.15 mol kg ) are measured by means of Taylor dispersion technique for this series and significant differences were found against previous published results for identical systems in pure water.
View Article and Find Full Text PDFMycobacterium tuberculosis surface proteins involved in target cell invasion may be identified as a strategy for developing subunit-based, chemically-synthesized vaccines. The Rv0227c protein was thus selected to assess its role in the invasion and infection of Mycobacterium tuberculosis target cells. Results revealed Rv0227c localization on mycobacterial surface by immunoelectron microscopy and Western blot.
View Article and Find Full Text PDFGiven the urgent need for designing a new antituberculosis vaccine conferring total protection on patients of all ages, following the line of research adopted by our institute, this work has identified Mycobacterium tuberculosis (Mtb) Rv3166c protein high-activity binding peptides (HABPs) which are able to inhibit bacterial invasion of U937 (monocyte-derived macrophages) and A549 (type II alveolar epithelial cells) cell lines. The presence and transcription of the rv3166c gene in the Mtb species complex was confirmed by polymerase chain reaction (PCR) and reverse transcriptase-PCR; Rv3166c expression was evaluated by western blot and cellular localisation confirmed by immunoelectron microscopy. Its presence was mainly determined on cell surface.
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