Polyacrylonitrile (PAN) fibers are widely used as precursors in the manufacture of high-conducting and mechanically resistant carbon fibers. The modulation of such fibers is carried out through electrospinning. In this work, we show the production and control of the morphology of nanometric-range PAN fibers for their potential use as precursors for high-electrical-conductivity carbon fibers.
View Article and Find Full Text PDFA deep understanding of the interactions between micelle-like aggregates and antineoplastic drugs is paramount to control their adequate delivery. Herein, Poly(NIPAM--SPMA) copolymer nanocarriers were synthesized according to our previous published methodology, and the loading and release of poorly and highly water-soluble doxorubicin forms (Dox and Dox-HCl, respectively) were evaluated upon UV light irradiation and pH-variation stimuli. Capillary electrophoresis (CE) coupled to a fluorescence detector (LIF) allowed us to specifically characterize these systems and deeply study the loading and release processes.
View Article and Find Full Text PDFThe electrochemical behavior of sp was studied using a glassy carbon electrode (GCE) modified with Nafion-dispersed oxidized multi-walled carbon nanotubes (OMWCNT). The morphology was studied using scanning electron microscopy (SEM), showing that the yeast sticks to the carbon nanotube surface instead of the glassy carbon surface. The redox couple Fe(CN) /Fe(CN) was used to determine the electroactive area and the heterogeneous transfer constant, which increased 80.
View Article and Find Full Text PDFHerein, three novel Pt(ii) complexes with formula [-Pt(Br-PyBenz-X)(Cl)(DMSO)] (1-3) having Br-pyridylbenz-(imida, oxa or othia)-zole (L) derivatives as potential bidentate ligands, under an unusual κ-N-coordination mode are reported. All compounds were obtained straightforwardly reaction of corresponding L and [Pt(Cl)(DMSO)] (DMSO = dimethyl sulfoxide), at 100 °C in acetonitrile, respectively. 1-3 complexes were characterized by analytical and spectroscopic data: melting point, FT-IR, Raman, UV/Vis and NMR experiments.
View Article and Find Full Text PDFConducting polymers (CPs), thanks to their unique properties, structures made on-demand, new composite mixtures, and possibility of deposit on a surface by chemical, physical, or electrochemical methodologies, have shown in the last years a renaissance and have been widely used in important fields of chemistry and materials science. Due to the extent of the literature on CPs, this review, after a concise introduction about the interrelationship between electrochemistry and conducting polymers, is focused exclusively on the following applications: energy (energy storage devices and solar cells), use in environmental remediation (anion and cation trapping, electrocatalytic reduction/oxidation of pollutants on CP based electrodes, and adsorption of pollutants) and finally electroanalysis as chemical sensors in solution, gas phase, and chiral molecules. This review is expected to be comprehensive, authoritative, and useful to the chemical community interested in CPs and their applications.
View Article and Find Full Text PDFThe use of soluble and highly oxidizing Ag(III) in the form of the tetrahydroxoargentate ion Ag(OH) is reported for the oxidation of surrogate organic recalcitrant dyes (i.e., rhodamine 6G (Rh6G) and fluorescein (Fl)).
View Article and Find Full Text PDFAnal Chem
October 2017
The simultaneous electrochemical quantification of oxidized (GSSG) and reduced glutathione (GSH), biomarkers of oxidative stress, is demonstrated in biological fluids. The detection was accomplished by the development of a modified carbon electrode and was applied to the analysis of biological fluids of model organisms under oxidative stress caused by lead intoxication. Nanocomposite molecular material based on cobalt phthalocyanine (CoPc) and multiwalled carbon nanotubes functionalized with carboxyl groups (MWCNT) was developed to modify glassy carbon electrodes (GCE) for the detection of reduced and oxidized glutathione.
View Article and Find Full Text PDFColloids Surf B Biointerfaces
November 2017
Nanoparticles (NPs) play an increasingly important role in the development of new biosensors, contrast agents for biomedical imaging and targeted therapy vectors thanks to their unique properties as well as their good detection sensitivity. However, a current challenge in developing such NPs is to ensure their biocompatibility, biodistribution, bioreactivity and in vivo stability. In the biomedical field, the adsorption of plasmatic proteins on the surface of NPs impacts on their circulation time in blood, degradation, biodistribution, accessibility, the efficiency of possible targeting agents on their surface, and their cellular uptake.
View Article and Find Full Text PDFPersistent luminescence nanoparticles made of ZnGaCrO (ZGO-NPs) are innovative nanomaterials that emit photons during long periods of time after the end of the excitation, allowing their use as diagnosis probes for in vivo optical imaging. During the excitation process, a part of the energy is stored in traps to further emit photons over long time. However, we observed in this study that some of the energy reduces molecular oxygen to produce reactive oxygen species (ROS).
View Article and Find Full Text PDFThe ZnGaCrO persistent luminescence nanoparticles offer the promise of revolutionary tools for biological imaging with applications such as cell tracking or tumor detection. They can be re-excited through living tissues by visible photons, allowing observations without any time constraints and avoiding the undesirable auto-fluorescence signals observed when fluorescent probes are used. Despite all these advantages, their uses demand extensive toxicological evaluation and control.
View Article and Find Full Text PDFAnal Biochem
June 2016
The self-assembly of peptide nanotubes (PNTs) depends on the structure and chemistry of cyclic peptide (CP) monomers, having an impact on their properties, making the choice of their monomers and their characterization a great challenge. We synthesized for the first time a new set of eight original CP sequences of 8, 10, and 12 d,l-α-alternate amino acids with a controlled internal diameter from 7 to 13 Å. They present various properties (e.
View Article and Find Full Text PDFZinc gallate nanoparticles doped with chromium (III) (ZnGa1.995O4:Cr0.005) are innovative persistent luminescence materials with particular optical properties allowing their use for in vivo imaging.
View Article and Find Full Text PDFJ Trace Elem Med Biol
October 2013
Exposure to lead induces oxidative stress and renal damage. Although most forms of oxidative stress are characterized by simultaneous elevation of nitrogen and oxidative species, lead-induced oxidative stress is unusual in that it is associated with a reduction in nitric oxide (NO) levels in the kidney. The role of NO in kidney injury is controversial; some studies suggest that it is associated with renal injury, whereas others show that it exerts protective effects.
View Article and Find Full Text PDFThe reduction of Cr(VI) to Cr(III) is achieved in a flow-by, parallel-plate reactor equipped with reticulated vitreous carbon (RVC) electrodes;this reduction can be accomplished by the application of relatively small potentials. Treatment of synthetic samples and field samples (from an electrodeposition plant) results in final Cr(VI) concentrations of 0.1 mg/L (i.
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